Exotic Driving Experience
Nov 21

How To Build a 12 Second Mustang 5.0 Fox-Body Part 2 Engine

Posted in Power Building


The engine I built for my red Mustang (1983 Mustang GT 5.0) is a 306 cubic inch using the original motor block. By the time I rebuilt it, it had over 100K miles on it. So I felt a complete rebuild was in order. Your individual situation may vary, but this is how I rebuilt mine. Now I realize that there are as many ways to build a 5.0 Ford motor as there are 5.0 Ford motors. So if this doesn’t sound like the perfect way to build one, feel free to build your’s however you want. After all it’s a free country, RIGHT…


Original 1983 Ford 5.0 block was cleaned, decked just enough to flatten them. Bored .030″ and honed WITHOUT torque plates. New cam bearings by Vandervell were installed.

Rotating assembly:

Was purchased as a balanced kit from PAW (Performance Automotive Wholesale). This motor was rebuilt MANY years ago, so some of these items/companies may no longer be available. But the information is still viable, you just might need to find a new source for the actual parts. I paid the extra money to have it balanced and recommend that you do as well. If you plan on racing your car it’s cheap insurance and makes for a much smoother running engine.

Kit included a recut factory crank, rebuilt rods, TRW L2482 pistons and pins +.030″, moly top ring, cast second, standard tension oil rings and Clevite rod and main bearings.

Stock harmonic dampener was reinstalled after it was inspected to be sure the rubber ring was still in good shape. If your’s has been oil soaked for years or the rubber is starting to come out of the groove,then by all means replace it. If it comes apart it will take your radiator with it when it goes. $$$

I used a double roller timing set to keep the cam timing properly set and slightly reduce friction. I can’t recall the brand of chain, but any name brand set should work fine for this application.

Oiling System:

Consists of a Milodon HV (high volume) Oil pump with the stock pickup tube installed. I did use the Milodon heavy duty oil pump driveshaft and advise you to do the same. If it breaks,by-by motor.  A stock Mustang oil pan finishs off the bottom of the motor.


Cam specs are .448″-204 deg @.050″ Intake , .472″-214 deg @.050″ Exhaust with a 114 lobe center.

Which looking back is a VERY mild cam, I was planning on adding a wilder profile bumpstick, but just never got around to it.

The car ran a 12.801 @ 104.44 in the quarter  with it, so I guess it wasn’t that awful. Hydraulic flat tappet lifters and single valve springs w/dampers were included in the kit.


Heads were Ford cast iron D8OE casting from a 70′s era 351W motor. They came with 1.84″ vs 1.78″ intake valves and 1.54″ vs 1.46″ exhaust valves on the original 5.0 heads.

Heads were milled .045″ to raise the compression some. NO I don’t know what the actual chamber sizes were… Steel shim head gaskets by Fel Pro kept it all together.

Stock sled type rockers and stands were used to actuate the valves, the original cast aluminum “Powered by Ford” valve covers buttoned up the top end.

Intake Manifold:

Edelbrock Torquer II single plane intake manifold was used with a 1″ open hole carb spacer to increase plenum volume.


Holley 650 double pumper carb topped off the manifold and supplied plenty of air for future power increases as needed. No need to go to anything any larger here. I know I’ll probably get a few naysayers who run their 306′s with a 750 /780 on it. But it’s just NOT necessary, witness my green car has run a 9.12 @152.44 with a 750 carb on it. Totally overkill on an 11/12 second car…


Hedman headers suppiled the 1 1/2″ primary, 2 1/2″ collector headers that are best described as “Mid-Length” headers. Longer than “Shorties” but not quite long-tubes either. At the track I sometimes ran  2 1/2″ x 7″ collector extensions that are in the motor picture, instead of the full mufflers (turbo mufflers) and 2 1/4″ exhaust system. Car picked up by .15-.2 second without the mufflers on.

The Rest:

5 qts. Castrol 20w50 Oil, Fram HP1 oil filter, stock Ford Duraspark electronic ignition and recurved distributor (all advance in by 2,500 rpm), Accel plug wires, and Autolite spark plugs.

If I forgot anything else let me know…



Nov 21

10 Lessons Learned From Engine Masters

Posted in Power Building

10 Lessons Learned From Engine Masters
by Andy Dunn ©2004
The Engine Masters Challenge is a yearly engine building contest created by Popular Hot Rodding magazine. 50 engine builders attempt to build an engine that produces the highest average horsepower and torque over a given rpm range.

On a dynamometer, you can analyze peak power and torque, or you can analyze average power and torque over a given rpm range; this competition only cares about the “average”. Many engine builders and racers worship the false god of “peak”. When trying to increase an engines average power, a builder quickly learns that changes with carburetors, headers, and spacers most often only teeter-totter the curve. This alters peak but does not change average. A 408ci engine might have a peak HP of 650 and a peak TQ of 550, but the average total for an rpm range of 2500 to 6500, might be closer to 500HP and 500TQ; these two numbers are added together produce a score of 1,000.

1. HEADS, CAM, COMPRESSION – Cylinder heads, camshaft, and compression, will always be the largest determinants for the final power output of any given engine. More than 95% of an engine’s power is derived by the “big three”; this was true in the past, and it will hold true in the future.

2. HEADS – Heads are everything. If you need more power, then you need more air-fuel mixture flowing through the system. When making a bigger explosion, larger quantities of air and fuel must pass through the system. I personally feel that port volume is over-rated and flow is under-rated. Porting must be consistent and efficient, but generally speaking, more flow means more power. Here is a quote from John Kaase, the 2003 and 2004 engine master champion:

“Chris Howe, labored two days on porting and valve seat work. We started the testing with full-size intake ports and later shrunk them down, which made very little difference at any rpm.” – Jon Kaase

This is a good example where port volume had negligible effects on flow and power. Kaase’s heads outflow the competition, especially at mid-lift. If you have the skills to pull it off, one of the ways to improve flow is to shrink the combustion chamber. This reduces the quench distance and places more of the chamber in the top of the piston. This makes for a very efficient chamber and is referred to by my Phd friends as a “Heron” chamber. This will not help peak flow but does help mid-lift flow numbers since the valves are un-shrouded sooner.

3. CAM – The camshaft determines the shape and size of the horsepower and torque curves. Camshafts are chosen to optimize horsepower and torque for a given rpm range. Drag racing, roundy-round, and road racing, all require power in different areas. Computer simulation software is very good at finding a starting point for picking the cam that will best match your specific power needs.

Lobe Shape (Lifter Acceleration Rate)
The computer is good at finding the correct duration. Lift is often limited by rules. The lobe shape should be as aggressive as possible, with practical engine life in mind. The lobe shape is probably the part of the cam design that is least understood by the public. The faster you can open and close the valve, the more efficient the system, and the more power you will make. You can design a camshaft with a 280/288 duration and 106 centerline many different ways, based on the many different lobe shapes. Use the computer, talk to the cam reps, and do some testing.

Belt drives are worth the investment because you can test various intake centerlines; wiggling the cam finds power.

4. COMPRESSION – More compression makes more power, assuming you can control detonation. Compression is often limited by rules. In the Engine Masters, contestants are limited by 92 octane pump gas. The most popular compression in the winner’s circle is 12.5:1. This ratio is too high for a street car, but it has a place in race engines on the edge. Many builders are scared of compression, it’s worthwhile to test and find the engine limits using a research mule.

5. MANIFOLD – If heads, cam, and compression are the “big three”, the intake manifold makes the “big four”. The manifold is an extension of the cylinder head. Most of the top engine masters test and re-test to find the manifold that best works for their mill.. I don’t have statistical proof, but I believe a manifold should flow the same or 5% better than heads at peak. If you have heads that flow 350, I would start testing with a manifold flowing in the 350cfm to 365cfm range. If your manifold flows less than your heads, air flow becomes restricted and total power will be reduced. If your manifold flows way more than your heads, the air gets lazy, loses some velocity, and power declines.

6. CARBURETOR – It surprised me and all the lads at Westech Dyno, when we put an 830cfm on my engine and did a baseline pull, then sleeved it up to 1050cfm, made one jet change and repeated the pulls, and the total average power was identical. Don’t get too hung-up on the carburetor. Pay the money ($700 – $1,500) for a good race carburetor, tune it, and don’t worry about it; retune it when conditions dictate.

7. HEADERS – I took seven sets of headers to the dyno; I was certain that one pair would have the magic.

Hooker (2 sets)
Mac Performance
Kooks (2 sets)
Once again, me and the lads at Westech Dyno were shocked that all of headers produced average scores within 5 points of each other. The headers had different peak horsepower and torque, but when you examine averages, the truth is revealed.

Most racers and engine builders want headers with primary and collector tube size diameters that are simply too large. My rule of thumb is to choose a header with a primary tube size, ten percent larger than the exhaust valve. Start in this range and test. In the 2004 engine master competition, most heads had 1.6″ exhaust valves, and most competitors were running with 1.75″ headers.

One of the more interesting tests we did while preparing at the dyno, was to run a set of 1.75″ Kook’s with a 3″ collector VS. a 1.75″ to 1.875″ stepped Kook’s with a merged collector. The difference in scores between the two headers was 1-2 points at best; that is 2 points out of 1,000. I’ve never been convinced that stepped headers or merged collectors make more power, and this test reinforced my beliefs. The two headers did have differing peak numbers, but peak is the false god…average is the true strength of the engine. Stepped headers and merged collectors are expensive. If merged collectors work, why do they work? It’s my belief that they work by simply reducing the size of the collector (people choose collector diameters that are too large).

I wanted to test my size reduction theory; on the fourth day of pulls, with a standard set of 1.75″ Hookers with a 3″ collector, I mounted a pair of 2.5″ collector reducers, inside the collector pipe. These reducers cost $25. We ran the test and picked up 2-3 average points. You can spend $500 on a pair of merged collectors, or you might try testing a cheap pair of collector reducers, fit inside your exhaust pipe. I think you will be pleased with the results.

8. BIG BORE SMALL STOKE VS.. SMALL BORE BIG STROKE – On paper, a big bore with a small stroke makes more power than a small bore with a big stroke. I’m not clear on all the reasons, but I do know that heads flow more efficiently over a bigger bore. When you add detonation to the story, suddenly the small bore big stroke gains the advantage. Kaase was one of the first to use this in competition.

“Because of the low test rpm range, I felt I needed the longest stroke and smallest bore with which the heads would work. With pump gas, detonation was a huge factor in the design of the short-block and heads. A smaller bore has less chance of detonation because it doesn’t have some far-off place for a secondary flame front to start.” – Jon Kaase

9. OIL – As much as I don’t want to believe it, there is hidden power in motor oil. When going from SAE 20w-50, to synthetic 30, and then to synthetic 20, 2-5 average points in power were found. Thin oil makes more power than thick; synthetic oil makes more power than regular. The gains aren’t huge but they do exist and they are clearly seen on the dyno runs.

A good oil pan allows oil to drain properly; a bad pan can cost power at certain rpm levels. Too much oil will effect power adversely and most people run with too much oil. Don Terrill suggests testing an 8qt pan with 5qts of oil and I have to agree. On the dyno, my engine master’s engine was happiest with 5.5-6qts.

“With a properly located oil pump pickup most engines don’t need more than 5qts of oil. Want to see how critical oil level is to power? Test it: If you have an 8qt pan, run it with both 5 and 8.”…Don Terrill

Too much oil pressure reduces power. It takes more energy to turn the reciprocating assembly as it slings off excess amounts of oil. Too much pressure can prematurely wear the cam and distributor gears. If you have an engine that won’t hold timing, pull the distributor and look at the gear. If the gear is worn, the cause may be excessive oil pressure or an improperly clearances distributor gear and shaft. A good rule of thumb is Terrill’s 10lbs of pressure for every 100hp.

10. TESTING – The best way to find the truth is testing. Engines are tested on dynamometers. Book the dyno for longer than you think; one day is barely enough time to break-in an engine and set the carb. Check the oil and water temperature every run and be consistent. Make good notes for every run. Only test one thing at a time. Use average horsepower and torque for your running range as the yardstick to compare changes. Average horsepower and torque are easy to find with SuperFlow software, just click File > Average > Columns and then select the RPM range you want to analyze.

Andy Dunn

May 23

10 Tips for Engine Survival

10 Tips for Engine Survival
by Don Terrill – RacingSecrets.com ©2003

1.) Less RPM – This is the number one killer of an engine. If you can make enough power at a lower RPM you should do it. Don’t forget missed shifts, now that’s a real killer.

2.) Optimal Coolant Temp – Both running an engine under power with too much water temp and too little temp can be harmful. High temps are the worst, with blown head gaskets one of the first signs of trouble. I’d say between 160′ and 210′ is best, never over 240′.

3.) Optimal Oil Temp – Low oil temp lowers oil flow. Higher oil temp breaks down the oil and gives way to the chance of metal parts coming into contact. Drag Racers usually race with the oil temp too low and stock car racers too high. Try to get near 200′.

4.) Less Compression – I’m a real fan of less compression. If you don’t need the extra power then there’s no need having the engine on melt down. If you’re in a competitive class then you have no choice. I’d keep it under 12 if you don’t need the power.

5.) Proper Ignition Timing – Too much timing leads to pre-ignition, which is like hitting the piston with a sledge hammer. Too little timing can lead to extremely hot exhaust valves. What happens if an exhaust gets too hot? The head eventually falls off. The only way to know the right timing is by dyno testing, track testing or reading the spark plugs.

6.) Tighter Lash – The weakest link in most engines today is the valvetrain and nothing kills it faster than too much lash. Just adding .010″ of lash can double the force on the valves. The only negatives to tight lash is usually less torque and the chance of holding the valve open if you go too far. Consult your cam maker for a usable range.

7.) Optimal Oil Level – You probably think I’m going to say too low is the problem, well if someone is going to make a mistake on oil level, 90% of the time it’s going to be too high. Too much oil can lead to the crank and rods whipping it up and adding air — not good. Most applications are very safe at 6qts.

8.) Proper A/F Ratio – Too rich a mixture can cause problems, for example carbon build up and washing the cylinders down. The real risk is from too lean a mixture. Just like ignition timing the only way to know the right mixture is by dyno testing, track testing or reading the spark plugs.

9.) Proper Clearances – Rod bearing clearance, main bearing clearance, piston to wall clearance, lash, etc., all are extremely important. You’d be shocked to know how few engine builders know exactly what these specs are. My advice, buy the tools and learn how to assemble your own engine.

10.) Proper Startup – I can’t tell you how many times I’ve seen this, someone starts their racecar completely cold and proceeds to rev the engine between idle and 7000 RPM. All engines need time to warm up. Better yet, how about oil and coolant heaters?


May 17

5 Tips For Tuning Aftermarket Electronic Fuel Injection Systems

by Benjamin Strader ©2004
1. Tuning EFI Systems on a Chassis Dyno

Sometimes when you are tuning an engine that is already in a vehicle on a chassis dyno, a lot of strange things can happen that you should be aware of.

First of all, it is important to keep a perspective on all the things that are happening. It can be very difficult to keep track of engine temperature, manifold pressure, air/fuel ratios, engine torque and horsepower readings all at the same time. It will take some practice to get comfortable with all of this while the wheels are spinning.

Try to pay attention to things like traction of the tires on the rollers. Many cars that produce big power can easily overpower the amount of tire adhesion to the roller, and this will dramatically affect the amount of power the dyno records. If you aren’t applying all the power to the roller, it can’t tell how much power you are making. On a dyno chart, this can normally be seen as an abnormal spike in engine speed and a corresponding drop in power and torque readings.

It is also important to remember that if you are recording Air/Fuel ratios with anything but the most high-speed exhaust analyzers that it is very common to get false readings when the engine accelerates too quickly. This happens because the engine speed changes so rapidly that the exhaust meter cannot update its sampling rate quick enough. By the time it processes a sample and displays it, the engine can be well beyond that operating range and be dangerously lean, or grossly over fueled. This makes it nearly impossible to record data and make accurate changes to the calibration.

Soft compound racing slicks and/or too little tire pressure can cause the tire to deform on the roller and actually decrease surface contact! Use a good radial street compound tire and strap the vehicle down tightly against the rollers.

2. Tuning Ignition Timing Tables

Whether you are tuning an engine on an engine dyno or a chassis dyno, you should always make sure that it gets tuned to the proper amount of ignition timing.

The best way to do this is to use a steady state holding pattern on the dyno and hold the engine to a specific RPM. Then load the engine to whatever site you wish to tune and record the instantaneous power readings.

When you make a change to add or subtract ignition timing, you will normally see a corresponding change in power output.

Using an onboard or aftermarket Knock sensor to check for detonation is the easiest way to find the maximum allowable ignition advance. However, if you do not have access to one, here is another way to get pretty close.

Advance the timing until maximum power is reached and begins to fall off when more timing is added. From there, back off the ignition advance one or two degrees and set it there.

Once you have made a few hard pulls on the engine at this setting, shut it off and remove the spark plugs. Inspect them for obvious signs of detonation or erosion. Pay careful attention to the J-shaped ground strap. You will notice that somewhere on the strap it begins to change color.

Ideally, when the proper timing is set, there will be enough heat in the combustion chamber to make the color change at about the center of the strap. If it changes more out towards the end of the strap, then there is not enough heat, and more advance is needed. Conversely, if the color change is near the bottom where the strap joins the plug, then take some ignition advance out in order to start the burn later and transfer more heat out the exhaust!

3. Using Ignition Timing to Stabilize Idle

When tuning a small displacement engine with very large injectors, you may have trouble establishing a good solid idle. This occurs because some ECUs do not have the injector driver strength to open and close these injectors for a short enough period of time and remain consistent enough to control the fuel.

Other than using a better quality fuel injection computer than what you already have, {assuming you’ve already purchased one}, there are a few tricks to help you along.

First, always make sure that your ECU is getting full battery voltage, if not more from the alternator. The ECU will have a much harder time staying consistent if the supply voltage is not up to par.

Second, use a little more ignition advance at idle than normal to help the engine produce slightly more torque and keep itself running a little better.

Lastly, try lowering the base fuel pressure just slightly to take the pressure off of the magnet coil inside of it. The less pressure it has to open the valve against, the easier time the injector driver will have when trying to open it. You don’t want to go down too low though, or poor fuel atomization can occur and make the poor idle situation even worse!

I have found that some of the better brand ECUs such as Motec, Autronic, and EFI Technology have very little problems controlling very large injectors on even the smallest engines. If you are looking at purchasing a fuel injection system for your project and idle quality is a concern, these might be good systems to look into. It is often beneficial to look at all the pros and cons of owning a particular brand of fuel injection system other than initial cost alone.

4. Using Oxygen Sensors

Tuning a modern fuel injected engine is nearly impossible without the use of an oxygen sensor. There are a few points to consider when finding a suitable place to mount the sensor in the exhaust manifold.

First, always try to mount the sensor so that it collects mixture data from as many cylinders as possible. Try to avoid having the sensor only get one cylinder’s exhaust whenever possible. On an with the cylinders laid out in a V configuration such as a V6 or V8 it is most desirable to place the sensor in the exhaust collector where at least half the cylinders come together.

On a small four-cylinder engine using a turbocharger, it is common to place the sensor just before the inlet of the turbo. This a good place to collect exhaust mixture information, however it is possible to overheat the sensor in this location. Most exhaust gas oxygen sensors can withstand up to about 800 degrees Celsius, but at times a turbocharged engine can easily exceed these temperatures.

Also be sure that there are no openings or cracks in the exhaust system ahead of the oxygen sensor. This can introduce fresh air into the exhaust stream and cause the air/fuel ratios to seem leaner than they are.

Lastly, some modern cars are now using air injection pumps to introduce fresh air into the exhaust stream in order to reduce exhaust emissions. This fresh air can also easily fool the oxygen sensor into thinking the engine’s actual air/fuel ratio is leaner than it really is. Be sure to disable any such devices before you begin your tuning.

Always protect your sensor from chemicals such as sealants, and remember that using leaded fuel will drastically shorten the life of your sensor.

5. Back to the Basics

When I was young and just starting out tuning engines an old man said to me “ninety percent of all your carburetor problems will be found in the distributor”. At the time, I thought he was just a kooky old man. After years of tuning, my own experience seems to have proven him right. Many tuning issues with both carburetors, and modern fuel injection systems are mistakenly blamed on the fuel system.

One thing to watch out for when tuning an engine using a modern fuel injection system is false information from an oxygen sensor when an engine misfires.

When an ignition event fails to happen, or the engine “misfires”, the oxygen sensor will want to read a leaner mixture than what really exists. This is due to the fact that the oxygen sensor can only read burned hydrocarbons. When the engine misfires, the unburned fuel doesn’t get recognized by the sensor, so it seems that there is a large excess of oxygen in the exhaust system.

Many novice tuners immediately begin to add fuel to the base fuel tables in an attempt to correct a lean mixture induced misfire. Not only does this usually not correct the problem, it often serves to make matters worse. Having too much fuel can also induce a misfire.

Always be sure that the ignition system is in good working order. Visually inspect spark plug gaps and set them according to the manufacturer’s recommendations. Also check that the spark plug wires are not burned or melted by the hot exhaust manifolds and check them for signs of wear.

It’s also a good idea to check all the power and ground supply wires to the ignition system and the high voltage leads to the ignition coils.

I have found that going back to the basics and thoroughly inspecting the ignition system will almost always rectify the problem!

ABOUT EFI UNIVERSITY Southern California based, EFI University (www.efi101.com) offers classes for individuals who wish to gain professional knowledge about high performance fuel injection systems in a structured environment! EFI University offers the most popular EFI-101 class, the challenging EFI Advanced class, and a Wiring Harness Workshop.

Benjamin M Strader, Senior Instructor at EFI University and author of “How to Build and Tune Custom EFI Systems”, has over 8 years of experience tuning and troubleshooting aftermarket electronic fuel injection systems. Recognizing the need for more education throughout the performance marketplace, Ben has formed EFI University, a company dedicated to teaching others about the correct use and implementation of aftermarket fuel injection systems!

EFI University

5 Tips For Tuning Aftermarket Electronic Fuel Injection Systems: by Banjamin Strader

May 17

Carburetor Q&A

by Barry Grant Inc. ©2004
Given that a four-barrel carburetor possesses something in the order of 200 components to allow it to function correctly, it’s no wonder the average enthusiast has the odd question about how it operates and why. Words and phrases like atomization, vacuum signal, fuel-metering circuits, etc. can be a little bewildering. So, here are a few of the basics with several useful illustrations to help explain. This article contains information that applies to a wide range of V8-engined machines, from street cars to tow vehicles, and from oval track racers to drag strip cars.

1) Q. Is air pushed or sucked into a carburetor?

A. With the exception of forced induction systems (centrifugal supercharger, or turbocharger – where air is forced through the carburetor), air is drawn through the carburetor (sucked) by the engine’s vacuum signal. The amount of air is determined by the strength of the vacuum signal.

2) Q. What is the difference between the straight-leg venturi booster, the down-leg booster, and the annular-discharge booster? Also, when should one be used in preference to another, and how does it affect jetting?

A. A straight-leg booster has, as its name implies, a straight leg, which protrudes from the body of the carburetor into the main venturi. Its discharge ring is situated slightly above the venturi’s most effective zone. Its discharge ring is slightly above the venturi’s most effective zone. The color red indicates the main fuel circuits, which connect with the main jets, the emulsion holes (blue) and the high-speed air bleeds located in the air entry on top of carburetor. The color yellow indicates the idle-fuel circuits, which connect with main-fuel wells, the idle-feed restrictors, the idle-air bleeds (also located in air entry on top of carb), and the idle-discharge ports and transfer slots in the baseplate.

B. A down-leg or drop-leg venturi booster drops the discharge ring lower in the carburetor’s main venturi where it operates in air of higher velocity, which draws more fuel than the straight-leg style of booster.

C. The annular-discharge venturi booster has a larger ring with multiple discharge holes rather than the single outlet hole of the straight-leg or down-leg style of booster. This has the effect of creating a venturi within the main venturi that produces greater vacuum than either the straight- or down-leg varieties and draws even more fuel.

D. In conclusion, the pros and cons of each type of booster are based largely upon its application. However, if each style is tested in the same carburetor with all else being equal, the down-leg booster will require smaller jets to flow the same amount of fuel than a straight-leg booster. And the annular-discharge booster will require even smaller jets to flow the same amount of fuel as the down-leg type.

3) Q. Mechanical secondary or vacuum secondary, which style of carburetor should I use and why?

A. Generally speaking, a mechanical secondary carburetor is preferred on vehicles with manual transmissions and on automatic transmissions with 3000+ RPM stall-speed converters. For automatics with less than 3000-RPM stall-speed converters, the vacuum-secondary carburetor is usually the better choice.

4) Q. How do I set the float levels and what effect do they have?

A. On Demon carburetors in street-driven applications, begin by setting the float levels at _ distance of the sight window. On race applications, increase the levels by setting them between _ and _ distance in the sight window. On Holley carburetors, remove the level plug and adjust the float level until fuel trickles from the open port. Changing the float levels alters the amount of fuel in the bowl (reservoir) and the carburetor’s ability to feed the main jets. By raising the float level the engine’s response is quickened. This is an adjustment frequently used to eradicate a lean stumble. By lowering the float levels, the activation of the main metering circuit is delayed and consequently produces a leaner mixture coming off idle. For street applications the latter condition is more economical.

5) Q. Does a bigger carb make more power? What’s the limit?

A. A larger carburetor can produce more power on a dynamometer, but under normal operating conditions can result in slower acceleration and lower efficiency of fuel atomization. Select the smaller carburetor, especially if you’re undecided about sizes. The smaller diameter venturii increase the velocity of the air/fuel mixture. As a consequence, it usually provides better acceleration and proves to be more efficient.

6) Q. Where should the fuel-pressure regulator be located and what type should I use?

A. The pressure regulator should be mounted close to the object (carburetor, nitrous system, etc.) that’s being fed with fuel. The further away the regulator is placed the greater the delay in its response (its opening and closing). A slower response causes fluctuations (spikes) in the fuel pressure. Regarding the selection of a regulator, specific vehicle requirements, but especially the type of fuel pump already in use dictates the type of fuel-pressure regulator required. For example, combine a block-mounted 15-psi pump with a throttle bypass; a belt-driven pump with a diaphragm bypass; a BG280 electric pump with a two-port regulator and a BG400 with a four-port regulator.

7) Q. How does weather and altitude affect carb jetting?

A. The more oxygen there is in the air the more fuel the engine will demand. For example, as the weather becomes colder (winter) or the altitude lower (closer to sea level), the air will contain more oxygen and the engine will require a larger jet size. In contrast, as the weather becomes warmer (summer) or the altitude higher (mountainous) the jet size needs to be reduced.

Carburetor Q&A by: Barry Grant Inc.

May 8

10 Undeniable Truths about Going Fast

Posted in Racing Tips

10 Undeniable Truths about Going Fast
by Don Terrill – RacingSecrets.com ©2003

1.) You will not go fast by reading the rulebook – You need to get into the pits and see what other racers are doing to go fast. If you build to the letter of the rulebook, you’ll be bringing up the rear at every racing event.

2.) Cheating exists in all types of racing – Some want to sweep it under the rug for the integrity of the sport, but non the less, it’s there. I personally hate cheating, but when your competitors are allowed to get away with murder, what are you supposed to do?

3.) 5% of people will dominate – This doesn’t just apply to racing, but our entire society. I know this may offend, but 95% of the people in the world are just along for the ride. Only 5% actually do anything of value.

4.) You can’t Bolt-On your way to #1 – You can’t order a number one qualifier out of a catalog. Fast racers will modify or design from scratch just about every important part on their cars.

5.) A full-time racer will outperform a part-time racer – I’m amazed how many part-time racers think full-time racers are cheating. I know it may be hard to admit, but they’re just better. Not because they cheat, but because of their experience.

6.) More money does not directly equal more wins – Stop thinking you’re losing because of money. I’ve seen world champs crowned with a tenth of the budget of their competitors. My advice, focus on what you spend your money on. Look at performance per dollar.

7.) Complaining about a competitor or his car will not make yours faster – Worry about you and your car, they’re the only things you truly control. There is no such thing as a perfect car or driver, both can be improved.

8.) The difference between good and great is tuning – I feel like I’ve said this a thousand times, give the same engine to 10 different racers, you’ll have 10 different results. The top tuners will always come out on top.

9.) You can make too much power – Unless you run the Bonneville Salt Flats, there’s a good chance you can over power the track. I see it all the time with short track stockcars — they almost all have too much low end power and spend half their track time at part throttle.

10.) An engineer with commonsense will rise to the top – It’s only a theory because the combination doesn’t exist :) Alright, I’m kidding, but you have to admit it’s rare. The easiest way to get the same thing is having an engineer team up with someone with commonsense.

10 Undeniable Truths about Going Fast, by Don Terrill

Apr 7

Homemade Horsepower

Posted in Power Building

Homemade Horsepower
by Fredrick M. Trippler Jr. ©2004
I have a white 95 Cherokee, 2.5 L , 5 speed, 2×4 SE with black trim. When I first bought it I couldn’t even keep up with traffic! I’m not rich by any means but I can be quite inventive and mechanicly inclined when I need to be. So most of what I’ve done I made myself and/or got the parts cheap or for free. I’ve spent 22 months on these projects,researching and testing. They do work and you will see a difference, believe me. Try these at your own risk to persons or property. I assume no responsibility or liability for anything posted here, including any federal, state and/or emmission laws, manufacture warrentees, insurance and/or safety. These are just ideas I’m passing along.

- A “true” cold air intake. $5.50 (From Home Depot)I made it from 3″ PVC drainpipe. First, I removed out my entire air box. Next, I cut a 3″ hole in my fender wall and stuck the pipe through my fender above my tire. I have plenty of room for the air filter because I have a 3″ suspension lift with stock height tires except they are 1″ wider. I glued on a 90-degree elbow and another short section. I had to make a brace to hold it in place so it didn’t bounce around. I also had to reroute my CCV and Charcoal Tank lines. I drilled holes in the rubber elbow coming off the throttle body and used gasket sealer to hold them in place.

-High flow cone filter. ($25.00 from Pep Boys) I clamped it on the end of the intake pipe so it sits in my wheel well right behind my bumper. I’ve had no problems with rain. I don’t advise driving in deep water though. (Laughing)If you are planning to, don’t cut the hole and keep the cone filter under the hood.

-E-Ram air. ($25.00)(Homemade) I went to a marine supply store and bought a 4″ 230 CFM 12 volt DelMar Bilge Blower. I used 4″ to 3″ PVC reducing couplings to make it fit. ($2.50 from Home Depot)I installed it in my intake with a switch in my door panel. When I flip the switch alot of extra cold air is pushed into my intake. A 2.5 liter engine naturally consumes 86 CFM (Cubic Feet per Minute) in 5th gear going 65 mph. So that means that I’m pushing 8 PSI (Pounds Per Square Inch)Not bad for a plastic blower (Laughing)

-Flowmaster Muffler.($38.00 on E-Bay) After the shop welded it in I had them cut off the rest of my exhaust pipe to lessen some back pressure, I only left 1″. Then they added an elbow and now my exhaust is in front of my rear tire. I also had them shorten the pipe that’s between the cat and the muffler to make it all fit right. I set off everyones car alarms when I drive by (Laughing)

-High Flow Universal Cat ($80.00 from Pep Boys)

-Shorter serpentine belt. ($30.00) that didn’t include A/C, which also eliminated 2 idle pulleys for less parasitic loss. I also removed the entire compressor and hoses to lesson weight by 30 Lbs. Do NOT bleed the A/C yourself. Any A/C shop can recapture the freon for you, then you can remove the compressor.

-Throttle Body Spacer. (Free) (Homemade) I cut it from a PI” plastic cutting board and used high temp gasket material on each side. I had to also put a 7/8ths” spacer under my throttle linkage bracket as well. I used a couple nuts and washers. Be sure the cable is stretched all the way out or it will idle real high. The spacer keeps the throttle body cooler.

- 4.0 Throttle Body ($42.00 from E-Bay)

-Copper core spark plugs. ($5.00)

-160 Degree thermostat.($5.00)and added Water Wetter. ($8.00) The colder your engine runs the more horsepower it has. Make sure you warm your engine a good 5 minutes when it’s cold.

-Manifold Intake Heat Shields. (Homemade) ($15.00) I purchased a roll of high temp gasket material from Pep Boys and three 10′ rolls of 2″ wide aluminum tape from a hardware store. I cut two 4″ x 6″ rectangles out of the gasket material and covered them with several layers of the tape. I slipped them between the intake manifold and the exhaust manifold to insulate the intake manifold from the heat. I secured them with coat hanger wire that I taped between the layers. Next I wrapped the entire intake manifold with metal heat tape all the way to the air filter minus the throttle body. After that, I took a turkey baking tin,($1.50)smashed it flat, folded it in half and wired that under my intake manifold. I drove for an hour, stopped, pulled the hood open and stuck my hand on the intake manifold. It was cold! (Try that at your own risk as well)

- Removed factory 30 lb. rear bumper and brackets and replaced it with a 65″ long 3″ dia. schedule 40 ABS plastic pipe with end caps which weighs next to nothing.($15.00 from a plumbing supply store) I secured it to the back end with two 3″ pipe clamps after I painted it black. I also painted behind the bumper area black also. Call me crazy but my steel jeep is still stronger than todays plastic and fiberglass crap.

-Complete Tune-up.($70.00)Cap, rotor, plugs, plug wires, fuel filter, all fluids etc.

-When your all done with everything, detach your positive battery lead. Turn your ignition key fully forward and hold for 30 seconds. Re-attach the positive cable. This will wipe your computer memory clean. It will rev high for a minute then settle down. Now drive “normal” for a couple days to reset everything so it can relearn the new mods. (Free)

Total Cost about $950.00! Not bad huh. If you had a pro shop do all this with performance name brand parts, were talking thousands! Some people call it “Ghetto” or “Redneck” mechanics. All I can say is that’s it’s way faster now and I still have my savings account intact. Hang onto your stock parts. You might need them come smog testing time.

Remember also, less weight = more horsepower & better gas mileage. Anything you can do to lesson that is a big help. Every 100 lbs. you can get rid of is 3 additional horsepower. It adds up real quick.

One thing for sure, I can keep up with traffic now!

-Another added bonus is my MPG went from 12 to 17.

-Load it like a Freight Car
-Polish it like a Show car
-Drive it like a NASCAR

Homemade Horsepower by: Fredrick M. trippler Jr.

Apr 6

10 Tips For Shaving ET This Weekend by Don Terrill

1.) More RPM – I’ve found that it’s just about impossible to have too much (higher number) gear in your car if your goal is the lowest ETs. Just keep adding gear ratio until you stop gaining ET, even if the MPH falls off. Remember: racing is usually ET not MPH.

2.) Jetting – If I had to guess I’d say that 80% of all race engines are jetted too rich. Some of the signs of a rich setting are an engine that misses or surges. Try jetting down two sizes and see what happens. Learning how to read spark plugs is my best advice.

3.) Ignition Timing – Go up or down two degrees and make a test. I’ve seen engines tuned with just a couple of degrees too much timing lose 30hp, so don’t think you can’t have too much.

4.) Oil – If you aren’t using synthetic oil already, try it, it’s worked every time for me. The other big thing is oil level, on a wet sump engine too much oil is a killer. No engine needs more than 6qts, no matter what the pan manufacturer says. In fact; too much oil is bad.

5.) Shift Points – If you’re going to miss your shift point, miss it early. A late shift is an ET killer, especially in the lower gears. Here’s a test: If you seem to really be knocked back into the seat after the shift, you’re late. The Reason? Your body went forward before the shift because of lack of acceleration.

6.) More Traction – Obvious subject I know, but here’s one I’ve seen missed more than any other traction aid: Weight. So many people are afraid to add weight to their car, but I would guess that 80% of cars could benefit from weight in the trunk. Don’t take my word for it, give it a try.

7.) Lower Coolant Temp – With all other variables being the same, lower coolant almost always makes more power. There are a lot of ways to lower the temp and I can’t mention them all here, but a problem I’ve seen more often than not is low coolant level. Make sure the radiator is full.

8.) Kill The Accessories – A water pump takes 10hp to drive, an oil pump takes 10hp and the alternator can take up as much as 35hp. Use a low drag water pump or electric drive and put a switch on the field of your alternator to turn off the drag during the run.

9.) Aerodynamics – Now I know changing aerodynamics of your car is not a simple thing to do, but there is one quick modification that I’ve seen work more than once; Lowering the front end of your car. I’ve seen drag cars pick up as much as .01 of a second in ET and 3 MPH in speed by just lowering the car two inches.

10.) Test Different Carbs – Carburetors all have their own personality and some just seem to work better than others. Buy two carbs that are exactly the same and you’ll have different results. My advice: test ever carb you can get your hands on and never get rid of a good one.

10 tips for shaving ET this weekend, by Don Terrill

Mar 28

Perfecting the Mustang 5.0 Launch Part 2

Posted in Racing Tips

9 Second 1993 Mustang 5.0 LX

In this article we’re going to learn what is required to perfect the 5.0 Mustang’s launch from the starting line. In the first installment we covered the tires. For the second installment we’re going to talk about suspension modifications, you can make to get you down the quarter mile quicker and faster.

The 5.0 Mustang uses a non-parallel 4 link rear suspension. Unlike the parallel 4 link suspension used on Pro-Stock racecars and other full on racecars. Ford used the non-parallel design from the factory as a cost saving measure, because it requires less parts to function, saving production costs. But like any cost saving measure, compromises are involved.

A parallel 4 link suspension requires either a panhard bar or a watts link to keep the reared centered in the car body. The 5.0 Mustang’s angled suspension arms keep the reared centered, without using any additional hardware. By using a combination of short control arms, and long control arms, both with different angles, the potential for suspension binding is very high. Ford compensated (compromised) for this by making the control arm bushings out of a soft rubber compound, that has some give to it.

Anyone who has drag raced their 5.0 Mustang knows all about wheel hop and fishtailing that these cars are notorious for. So the first thing that needs changing is the rear control arms. Ideally the car should use a control arm like the Mega-Bite Sr. which has Heim joint rod ends, to eliminate suspension slop and prevent binding. They also have the added benefit of being adjustable for length, allowing you to center your tires in the wheel well openings. It also will allow you to adjust the pinion down angle, to further adapt launch characteristics. This one suspension modification alone should make a noticeable improvement in your cars starting line antics. No more wheel hop or fishtailing, and much easier to keep in a straight line down track.

The next suspension modification that needs to be remedied is a change to an adjustable shock absorber. If funds are low you could get by with a 50/50 rear shock, and either a 70/30 or 90/10 front strut. But if funds permit, you’ll be much better off in the long run with an adjustable shock/struts. Quality products are available from companies like Competition Engineering, AFCO, Koni and others. Having the ability to adjust your shock settings gives you the flexibility to adapt to future mods in the power department. If you’re like most 5.0 Mustang racers you’ll be adding more and more power to your car as time goes by. What works for your launch at one power level, may prove totally wrong with 50-100 more hp in your engine.

If your street/strip car is more strip than street. More aggressive suspension mods can be performed. Items such as Eibach’s Drag spring set allow for much better weight transfer upon launch. Removing the front anti-sway bar is also another way to loosen up the front end for better launch at the drag strip. It’s also very heavy, and removing it will shave a few pounds off the front end weight of the already nose heavy 5.0 Mustang. Stock weight bias is typically around 57/43 stock, which means 57% of the cars weight is on the front wheels. Not exactly conducive to great traction, which is why I will be addressing redistributing some of that weight in a future article.

For now I would not recommend removing the rear anti sway bar from the car. It serves a purpose, that being to help keep the rear end of your 5.0 Mustang from torquing over to the passenger side when launching. As you add more power to the car a change to an aftermarket anti sway bar or even a double bar system may be in order. But the factory rear bar will take you deep into the 11 second range and perform admirably.

Aluminum Caster/Camber plates are another worthwhile suspension mod. Caster/Camber plates are made by Steeda and others. These devices replace the flimsy factory part, Replacing the rubber bushing upper strut mount, with a much more precise ball bearing, and allow you to add additional caster to the front end alignment. Adding caster to a drag race 5.0 Mustang helps you keep the car centered in your lane and adds stability at the top end. Adjusting your alignment to provide 5-7 degrees caster will help tremendously in keeping you going straight ahead.

Replacing the factory tie-rod ends with an aftermarket bump-steer kit is another trick that will work very well for keeping you from running off the racing surface. Bump steer is the change in toe-in that your 5.0 Mustang experiences when the front end rises and falls. From the factory the Ford Mustang usually has a bit of bump steer built in. Once you start changing things it only gets worse. These pieces will need to be installed at a chassis shop, but are well worth the expense, for the stability your car will receive from them.

Feb 5

460 Ford Powered 1978 Ford Fairmont Futura

Posted in fun stuff

A 1975 Lincoln Towncar gave it’s life (460 & C6 Trans) so that this car could live. I put this combination together after the factory-installed 200 straight six seized up on me. The body & paint went kinda haywire, it originally had a vinyl top. I removed that when the thing started rusting through from the inside.

The car was put together in 1981 when I was only 21 years old, so speed was (and still is) more important to me than fancy paintjobs or chrome parts. Besides imagine the look on the other guys face when you blow right past his car in this one! Thankfully my income has been increased since then, so subsequent racecars have looked better than the old 460 Ford powered 78 Fairmont Futura here.

Now-a-days you can buy a set of motormounts/trans mount and headers for a Fox-Body Mustang and be rocking a 460 in no time flat. But back in 1981 I was blazing a trail by myself. Some plate steel made the mounts and a chassis builder custom made the headers for me, highly modifying a set from a Torino.

Even though the car never made it down the quartermile due to budget constraints, it was a lot of fun to drive. Turned more than a few heads with the 460 Fairmont. The low compression emissions motor didn’t produce a lot of HP stock, but it came stock with around 500lbs.ft. of torque. More than enough to push the flyweight Futura around.