The first thing you need to do is determine the benchmark for performance you will use. Ultimately, the most accurate benchmark is track use. At a racetrack, performance levels may be very accurately measured and evaluated. On-track performance is not only a measure of how powerful an engine is but also of how well thought out and executed the vehicle build is. I believe putting a vehicle on a race track is a much more accurate indicator of engine performance than a dyno is, especially a wheel dyno that calculates HP and TQ at the wheels.

Now I’m sure that a lot of people will disagree with this statement, but there is truth in it. Many people seem to think that dyno numbers are the ultimate reflection of what an engine can accomplish. Big dyno numbers are regularly tossed around and taken as gospel. The fact is, dyno numbers are easily manipulated, and that more than one dyno sheet is inaccurate because of this. Sometimes these are just reflections of poor calibration, in other cases this is due to poor operator operation. The worst is deliberate, where a dyno operator manipulates the dyno in order to inflate the output numbers. A dishonest operator may do this in order to support their personal claims.

Another issue with dyno numbers is that the average enthusiast is looking primarily at the peak numbers the engine is making. Do not pray to the false idol of peak HP and TQ. Engines with lower peak numbers, but higher average numbers will outperform an engine with the opposite dyno numbers in virtually all real world applications.

I have worked on many vehicles that ran numbers at the racetrack that were substantially slower than what the dyno sheet indicated they should run. Often, by re-tuning the vehicle I can make the vehicle perform significantly better at the track, even though we may be sacrificing some peak numbers.

I have also worked on many vehicles that the results on the dyno sheet could not be duplicated. In one situation two other wheel dynos showed about 2% deviation from each other, but almost 18% less than the original dyno sheet. That translated into about a 65 HP difference in peak numbers at the wheels.

Now a dyno is a tool, and when used effectively, it’s a good tool. But when building a car, I believe it’s better to build for a certain race track goal. For example, let’s assume we are working on a 60’s vintage musclecar. The owner has no intentions of racing it but wants it to perform very well. He decides that a vehicle that will run 13.0 seconds in the quarter mile is what he wants. The HP numbers required to make the vehicle achieve that level of performance are calculated, and engine components are chosen based on that number.

Ultimately, he may not be able to claim the high HP and TQ numbers some enthusiasts brag about, but chances are pretty fair that his car will outperform theirs. You can always tell the owner of a car like that. He’s the one grinning from ear to ear.

(In Part IV I will share some information on choosing a realistic performance goal based on drag strip performance.)

Look at the entire vehicle, starting with the brake, steering, and suspension systems. Note anything that needs to be addressed and make a complete list of what’s needed. This list is the blueprint for the build.

Now that the vehicle needs have been identified, determine your needs. Before getting too involved with the repairs and modifications, think hard about what you want the end result to be. Do you want a factory correct restoration, mild performance with stock appearance, or a more radically modified car? The answer to this question is important because it will allow you to make educated purchasing decisions and avoid spending more money than necessary.

Money is always a factor. Take care of the items that are most in need of repair first, again focusing on safety. If the brakes are OK, the suspension worn but serviceable, but the car steers like a cattlecar, make the steering repairs first.

Keep the performance goals of the vehicle in mind. If you are planning on installing a 400 HP engine, the rest of the car needs to be able to handle it. The brakes will need to be very good, and the suspension and steering will need to be tight. Don’t try to save money by taking shortcuts or making patch repairs when the goal is a big HP vehicle.

For example; Let’s assume the build is a 60’s musclecar. The suspension, steering, and brake systems are shot. You want the car to have a relatively stock appearance with the performance of a modern vehicle. Instead of rebuilding the systems with factory replacement parts, upgrade to more modern parts. Convert the drum brakes to disc brakes, change to better suspension bushings or modern suspension, etc. You will spend more money now, but will ultimately save money and time by making the repairs once instead of twice.

(In Part III, I’ll write about engine modifications.)

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This is a tough question to answer, but it is also a very important one. I work on a lot of cars. Many times I work on them after a lot of money has already been spent, and the levels of performance are much less than expected. In order to avoid spending money and getting little in return, the vehicle owner should make some decisions before undergoing their wallet-ectomy.

The first thing the owner should do is decide what the intended use of the vehicle is. A car used for drag racing has completely different suspension requirements than one driven on the autocross course. A daily driver will need to be built differently than a car that rides on a trailer to the races or shows. Show cars and collector cars have different requirements; the collector vehicle should be factory correct, show cars can be wildly modified.

The type of vehicle has a lot to do with the work that it will need. In some cases it actually makes more sense to build a different car. A car in bad condition will take a lot more work and money to build than one that is in good shape to start with. A heavy car with a small engine needs more work and money to perform at the same levels as a light car with a larger engine. In both cases it is often cheaper to sell the car and buy one better suited to the intended use.

Probably the hardest cars to build are dual purpose cars. These are cars that not only are regularly street driven, but are also expected to perform well at some type of race. These cars have to idle well and not overheat in traffic, yet have high enough levels of performance to be competitive at the races. These cars run a fine line between two types of use, but building one is very rewarding.

Once the intended use has been determined, the entire vehicle needs to be evaluated. Make a list of everything the car needs to make it work the way it’s supposed too. Rank everything on it by order of importance to the end goal and get to work. Stick to the list and you will save yourself some money in the long run.

(In Part II of this blog, I will go into a little more detail on how to decide what to do first.)

There, I said it…I’m addicted…and…I don’t want to be cured.

So, how do you know if you are a Gearhead? What are the signs of addiction? The following is a partial list of warning signs that you are a Gearhead. They aren’t in any particular order because they are all equally important.

THE WARNING SIGNS OF GEARHEAD

1)You mess around with your car all the time. Modify this, add that.

2)It’s a cold and cloudy day, the ground is muddy and you are laying under a car in a wrecking yard.

3)You have bought and sold parts at swap meets.

4)You have an oxy-acetylene torch in the garage. Fire and steel…That’s primal.

5)You wake up on a creeper.

6)There’s more than one engine for your car. The one that’s in it and the one being built.

7)It’s so hot you could fry an egg on the sidewalk. You’re dripping sweat at a racetrack.

8)Not only do you watch the races, you’re junks been on a racetrack.

9)You plan vacations around races and car shows.

10)There’s at least one model car in your living room.

11)There are car parts hanging on the garage wall.

12)You collect parts for your dream car…Even though you don’t own it yet.

13)You’ve cut the crap outta yourself, covered it with electrical tape, and kept working.

14)Up at midnight? Must be getting ready for tomorrows race.

15)Speaking of racetracks, you can eat their food and not spew.

16)You work on all your buddies cars…For beer.

17)You don’t think twice about spending serious coin on a tool, even if it means you eat cheap this week.

18)You like the smell of an old engine being torn down, burnt tranny fluid, and gear oil.

19)You’ve kept food warm on an engine.

20)A buddy needs a part. You have a spare on a shelf in the garage.

So there you go, a partial list of the signs of Gearhead. In future entries I’ll go into more detail on ‘em all.

(wanna add a Gearhead sign? get on it, if I like it, it stays)