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Horsepower Hide and Seek

Horsepower Hide and Seek
By Don Terrill (c) - www.RacingSecrets.com

More power, it's there, you just have to know where to look for it. Sometimes it's right in front of you and other times you'll find it in the most unexpected places.

Look at the Raw Numbers
I while back I wrote some software for myself that showed where the piston was located and how fast it was moving. I then overlaid Cam-Doctor data to show me what the valves were doing in relation to the piston. Lastly I added airflow numbers - It was a huge eye-opener.

Look at it Graphically
I love the raw data, but sometimes the amount of information is overwhelming and can only be understood if viewed graphically. Fire up Microsoft Excel and SEE what you can learn from the numbers.

Look to Other Forms of Racing
Over at Racing Road Trip I've been documenting my quest to view every type of racing known to man. I have a long way to go, but already I've received a huge education. The Human Powered Vehicle (HPV) race in Wisconsin and the Soap Box Derby in Ohio were a couple of my favorites. The one I'm dying to see is airplane racing - It looks crazy on TV.

Look Outside of Racing
Taking it one step further, let's forget about racing all together and look to other industries for inspiration. Aviation and aerospace should be at the top of your list.

Question Conventional Wisdom
Are there things you believe even though you haven't verified them for yourself? I'll bet there are. I'll bet there are a lot of them. What widely held beliefs do you think warrant another look?

Start from Scratch
How would you design an engine if you could start from scratch? Would you use poppet valves and push rods? I doubt it. The cost of a complete redesign will probably stop you in your tracks, but it's still a worthy mental exercise.

Forget Everything you Know
Take it to the extreme, what if you could look at the task of propelling a vehicle with virgin eyes? How would you do it? What energy source would you use? Gasoline? Alcohol? I'm sure you can think of better, much better.

Talk to Non Racing Gurus
When you run across smart folks, I don't care what field they're in, ask them questions. They just might give you a fresh idea - something you've never thought of before.

Want to send off a nasty email about how wrong I am? Well, first read this and then write your own article.

10 Early Season Power Tips

10 Early Season Power Tips
By Don Terrill (c) - www.RacingSecrets.com

It's your first time out this year and you're not happy with the results - Your car feels short on power. At this point most racers will go on a witch hunt to find the one item causing the entire shortfall. Rarely is this the case, more often it's 10 little things adding up to one big problem. Here are 10 I see over and over:

(1) Ignition Timing
Some engines are very touchy to ignition timing - I've seen 2 degrees too little cost 10hp or more and 2 degrees too much cost over 30 hp. An engine or chassis dyno is the best way to find the sweet spot. If that's not an option, learn how to read spark plugs.

(2) Air/Fuel Mixture
If you're still running out of the box jetting on your carburetor, odds are it's fat and costing you power. You can't blame the carb manufacturers for wanting to play it safe and avoid a mass of angry customers who race at sea level in 40 degree (f) weather. Learning how to read plugs is critical to getting it right, but most applications can benefit from going leaner.

(3) Gasoline Mix
I can't even remember the last time I ran gas straight out of the drum/pump. The trick is getting as much oxygen content in the gas as possible with just enough octane to stay out of detonation. Less than max compression engines have the most to gain from getting the fuel mix just right. If you're brave enough and the rules allow it, you can try some of the additives meant to boost oxygen. Depending on the amount oxygen added, you may need to re-jet.

(4) Forced Air
This is not the time to consider a blower or turbo charger, but what about a hood scoop or cowl? For a forward facing hood scoop make sure it's high enough to catch the positive pressure coming off the front of the car. A rear facing cowl hood makes it a lot tougher to find and capture that positive pressure - testing with a manometer will help. With either setup, make sure you've got a tight fitting air pan or your efforts will be for naught. Also, if the car slows down when you seal the air pan, your scoop/cowl is in the wrong spot.

(5) Cold Air
You can easily find 10 hp for every 10 degrees (f) lower you can make the air going into the engine. A hood scoop or cowl is best, but if you're forced to pull air from under the hood, there are still some things you can do: (1) Create a "Cold Air Kit" that pulls air from in front and to the side of the radiator. (2) Paint the top of your hood white to stop the sun from adding to the problem.

(6) Oil Volume
On a wet sump engine you lose approximately 10 hp for each additional quart of oil you run, so stop letting oil pan manufacturers dictate how much oil you run - nobody needs 12 quarts of oil. On a dry sump engine the oil level in the pan is controlled by the scavenge side of the pump, so to keep the level as low as possible consider more stages and bigger hoses.

(7) Oil Pressure
You can lose as much as 5 hp for each additional 10 psi of oil pressure you run. You lower it at your own risk, but I've seen engines making over 700 hp run fine on less than 40 psi. For dry sump engines it's an easy adjustment, for wet you'll have to decide if it's worth the effort.

(8) Oil Type & Weight
The debate was over a long time ago - synthetic oils do free up power - You can expect 5 to 10 horsepower when switching from mineral based oils. Weight should be matched to rod/main bearing clearance and the temperature the oil runs at - the more the clearance or the higher the temperature, the "thicker" the oil required.

(9) Shift Points
It cost nothing to make sure you're shifting at the right rpm. If you have dyno numbers, try a fuzz over peak power and test from there. Of course you can always use your internal dyno - our ability to feel g-force - It's crude, but better than nothing. Here's a clue: If you feel pushed back in the seat immediately after a shift, you were late - which is a lot worse than being early.

(10) Gear Ratio
Ignoring traction or longevity issues, the majority of cars don't have enough gear ratio. Drag racing and short track stock cars should top out well over peak power. Big track stock cars or any type of racing where you spend a lot of time at one rpm should hang closer to peak power.

Want to send off a nasty email about how wrong I am? Well, first read this and then write your own article.

Last Minute Horsepower

Last Minute Horsepower
By Don Terrill (c) - www.RacingSecrets.com

Ok, you're almost finished with your new engine - all the machine work is done and you're ready to assemble. But, you're starting to worry about power - it won't be enough. Now what?

Well, this is no time to fiddle with cubic inches, compression or new cylinder heads, but there are still things you can do to help power that won't require starting from scratch.

Camshaft
If you've got enough piston-to-valve clearance (measure it, don't assume) and you're not sure about your cam choice, maybe it's time to sell it and try again. For more power focus on picking the right intake duration and then getting as much lift as possible for that duration. Make sure the valve springs (and your maintenance schedule) can handle the increased stress from a more aggressive lobe design.

Rocker Arms
More intake rocker ratio can be a real help - especially if you think the cam is a fuzz short on duration. In addition to the warnings above, make sure the increased rocker ratio won't create clearance problems between the side of the pushrods and cylinder head. A rough estimate for the piston-to-valve clearance lost with a 0.1 increase in rocker ratio is 0.1 x lobe lift @ TDC (a spec listed by most cam companies).

Intake Manifold
Not a ton of power to be found here, but an easy swap. If your manifold was designed 40 years ago (many were), you may want to look at some of the newer offerings. Also, don't get all caught up in having a perfect gasket match - As long as the manifold port is smaller, but not radically smaller, than that of the cylinder head, you'll be fine. Don't believe me? Back to back it on the dyno.

Carb Spacer
Most applications will benefit (max power) from having the tallest carb spacer the hood will allow. Try a 4-hole spacer nicely blended into an open - It doesn't work on all applications, but it works more often than not.

Carburetor
If your carburetor still has a choke tower on it, you're leaving at least 1ohp on the table. Upgrade to a newer high flow model or modify the one you've got - which is not that hard. http://racingsecrets.com/holley_carburetors.shtml

Headers
Not that cheap anymore, but a simple bolt on. If your headers are the wrong tube diameter, replace them. If you think you've got the right tube diameter, then cut off the collectors and get a set of merge models - they do work. Buy the slip on models if you want to do some tube length testing by adding extensions between the header and collector, or if you want to try different collectors down the road.

Oil Pan
Wet or dry sump, anything you can do to get the oil away from the crankshaft will help free up horsepower. In fact, it's impossible, from a power standpoint, to get the oil pan too big or too deep. And when you're done, don't defeat the whole purpose by adding more oil to the pan.

Want to send off a nasty email about how wrong I am? Well, first read this and then write your own article.

Competing with the "Big Guys"

Competing with the "Big Guys"
By Don Terrill (c) - www.RacingSecrets.com

This will go against how society has taught us to think, but I believe it's dangerous to assume someone else is better or smarter just because of their position or title. I'll even go one step further and say it's dangerous to think that way about anyone, at anytime, on any topic.

Use this as your default until you see proof to think otherwise.

Cornell University Findings:

Top performers tended to underestimate their own performance compared to their peers. The researchers found that those participants fell prey to the false-consensus effect, a phenomenon where one assumes that one's peers are performing at least as well as oneself when given no evidence to the contrary.

Not only that, but we overweight certain evidence, like seeing Nascar crew members on TV and assuming they're the best of the best - From my experience, only 20% of them actually deserve to be there.

Here is a litmus test for deciding if you can move to the next level of racing and compete with the "Big Guys": Are you winning at your current level? Yes? You're ready!

Then, just keep moving up until you prove the Peter Principle. (Which I probably did by writing this article) http://en.wikipedia.org/wiki/Peter_Principle

Want to find your level of incompetence in a hurry? Try the Leapfrog Theory. http://racingjob.com/2005/08/leapfrog-competition.html

Now for the other side of the coin: Cornell not only discovered that top performers underestimated their ability, but that bottom performers overestimated theirs. Yep, I'm sure we all know a "few" of these.

Summary:

Question all of your assumptions about the competition - because many are unfounded.
If you've won at your current level, create a plan to move up - it's time.

photo by suddencomfort2

Want to send off a nasty email about how wrong I am? Well, first read this and then write your own article.

First Time Here?

Horsepower Hide and Seek

10 Early Season Power Tips

Last Minute Horsepower

Competing with the "Big Guys"

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