How much horsepower can you get?

G

Gearheadotaku

New member
Since IT mods are fairly limited as far as engines are concerned, how much extra power is being found and how? Not trying to get anyone to give up their secrets, but trying to find out which cars have the most to gain under the rules and how to do it.
Thanks
 
That is a big question...kinda like "what is the meaning of life?" :D
Seriously, besides that, I have found that pretty much no one will divulge hp numbers on here B)

I, on the other hand, am a backmarker, and will tell you that my specific car prolly doesnt have much hp to be gained with IT mods. Now, I have not had a pro built motor yet, but have done some of the mod's allowed in IT to a junkyard motor, and have gained about 8hp or so. I recently dynoed at 93 hp at the wheels...my torque figures were so low I dont think the dyno was able to measure it :lol:

I would imagine that a built to the hilt motor for my car (89 suzuki swift GTI) would see about 15 or so hp over stock, which is about 83 hp at the wheels :lol: :lol: :lol: :lol:

Now, seriously...
My car is light and pretty aero, so I am not doing as bad as it sounds in the hp department...I would rate it around towards the rear of the midpack hp-wise

Other engines from other manufacturers may see a bigger increase in hp over stock.
 
I'll tell, LOL.

My old (now blown up motor) was 106Hp at the wheels on both a dynajet and a Dynapak hub dyno. Torque was 101 lb ft. Thats a 1st gen ITA motor.

My new motor feels better, but I haven't gotten the numbers on it yet. Soon.

In ITA, I can't divulge what car has what HP. But I can give some ranges. CRXs are thought to put down a bit over 130. Integras are in the 130 high and then some range. 240SXs are said to run about 150. Miatas are in the low 130 range.

Certain engines WILL gain more than others in IT trim. Old rotaries need to breath to make power, and the 1st gen, for example, has a process number around 130, or in the 150 flywheel range. Stock, it's 105 or so, so thats a lot of gain.

A porsche 911E, which is an ITS car, has 165 stock. But it's air cooled, and it's got an MFI system that pretty much locks in what you can do with the car. In IT trim, you'd be lucky to see 190 flywheel, VERY lucky. So the gains aren't great on that one. Add to the low return on investement, the high cost of doing the build, and you can see why 911s are never seen in IT racing.

The process takes into account, to a certain degree, the gains that are expected from each car,but even at that, some cars will be overacheivers, while others won't measure up.

Some guys use valve sizes as their indicator of whether to race the car.

But there are a lot of things to consider when choosing a race car.
 
I've never been secretive about our results. Last dyno test, immediately after ARRC '05 and using the same exact engine I won with this year (new spark plugs, oil, and air filter), put out 147hp and 133(?) ft-lbs of torque, at the hubs, on a DynaPack. The stock engine was rated at 140hp at the crank.

How? Prep and details. All parts machined perfectly. Perfect balance. Perfect port-match. Dyno testing incorporating perfect adjustments. All the little details add up...
 
Come on Greg...'fess up. Info found circulating among the Honda drivers has your engine putting out more in the 240-260 range! ;)
 
"How much horsepower can you get?"

A heavily moded Delta IV rocket is good for about 17 million hp. My neighbor works on the program over at the Cape, and on the recent launch for the stereo solar probe to the sun they had to crank up the boost or, as he puts it, "We had to kick it hard."

Okay, so it's OT, but still rather cool. B)
 
"How much horsepower can you get?"

A heavily moded Delta IV rocket is good for about 17 million hp. My neighbor works on the program over at the Cape, and on the recent launch for the stereo solar probe to the sun they had to crank up the boost or, as he puts it, "We had to kick it hard."

Okay, so it's OT, but still rather cool. B)

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But, were all his mods IT legal? :D
 
Come on Greg...'fess up. Info found circulating among the Honda drivers has your engine putting out more in the 240-260 range! ;)
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Must have, eh? ;)

Nah, just optimistic DynoJets. I'm sure I'd hit some "impressive" numbers if I used one.

The nice part about the ARRC tear-down is that we were not particular as to whom looked over our shoulders. As long as they stayed out of the crew's way I did nothing to stop competitors from looking as much as they wanted. Our engine compartment and combustion chamber was there for everyone to see, and the head and cams sat unsupervised on a bench against the tech shed wall for anyone to walk by and look at. Our exhaust sat on the floor for all to see (and certainly caught Ruck's attention) and the rest of the car sat open for several hours.

So, given a stock engine puts out 140 ponies (~120 whp), who here really believes that IT-prep engines are putting out the silly numbers we keep hearing about? 147 at the hubs is ~173 at the crank; which numbers do you think are the most realistic?

I keep threatening to meet up with Rick Benazic (Integra) and Andy Bettencourt (Miata) at a common dyno, same day, for direct comparisons. Maybe it's time we make that happen (after we re-assemble the engine, of course...) - Greg
 
If I were looking at this type of thing as a basis, I would try and learn all I could about some models. Poor factory design may be the way to go. Meaning - when you 'improve' to the rules, you get some good gains. Headers are the best example. Drop some headers on a car with a crappy (set) exhaust manifold, and you have some good gains. Cars with good designs from the factory (like the Miata) don't show much gain at all. Look for cars with poor oem intake designs that could benefit from the open intake rules.

ETC. ETC.
 
Correct me if I'm wrong, but I thought the generally accepted rule of thumb was an 18-20% gain. Or generally you're flywheel hp will become your at the wheel hp. Like others have mentioned, this is highly dependant on many factors, some outside the scope of IT motor preperation rules. Say one car's stuck with really small valves and siamese ports, like was common on some of the really old motors of yesteryear, really flat intake runners, or a really mild camshaft pattern. Not much can be done to overcome these issues without making the motor not IT legal. So choose wisely with your eyes open to what's allowed, what's not, and the potential that's between the two.

James
 
Since IT mods are fairly limited as far as engines are concerned, how much extra power is being found and how? Not trying to get anyone to give up their secrets, but trying to find out which cars have the most to gain under the rules and how to do it.
Thanks
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I'm sure almost every car classified has been investigated and researched to the nth degree. Not to sound negative, but the chance of findind the next over dog is slim.

If you are new to racing, I would suggest buying a known entity. Again, I don't want to sound negative, just trying to save you a little frustration. Ask me how I know!! :lol:
 
Of course, you have to anticipate any over-achievers, then everyone else falls below that. 25% makes perfect sense when drive-line losses are estimated as between 17-27% Thus maybe you have a 18% drive-line loss but a 22% gain in power, you'll see a 4% over stock flywheel hp gain at the hub. Still that's reasonablly close.

James
 
Jeff really hit it on the head...
Your best bet is to go out and buy a known quantity...There are IT cars in the classifieds that will save you thousands, and they are already set-up and competitive.

If you want to spend thousands more, and devote all of your spare time to building an unknown quantity...and after all that trouble, probably not hitting the mark anyways...then go for it.

I hate to sound so negative, but I did what your doing (except I knew that my car had been very competitive in the past with other drivers), and built it from the ground up. My first mistake was building a car that no one else is running and parts are hard to find for.

I have at least 12 grand in my car, and it was free! My dad had two sitting in his backyard, and a junkyard motor in the garage, waiting to be installed.

For around 7 grand, you could have bought, say, the bildon ITB Golf that was in the classifieds recently.
My car, at 12 grand, isnt even in the same area code so far as development and outright speed. I have basic Koni's, a junkyard motor, etc...

Unless your a genius pro car builder...you will never build a competitive IT car for anywhere close to what you would pay for one out of the classifieds...Do yourself a favor, save some money, and your precious time, and buy a built car.

I beat myself over the head everytime I think about my choices in racing....I could have saved so much money and time, and maybe be running at the front of the pack instead the rear
 
As others have stated, that is a loaded question.

Please remember that horsepower is only one of many factors in a racecar. If you can't get it down on the pavement, no amount of power will do you any good. A good handling car is worth 5-10 hp any day (others will disagree on that, but that is my experience). Your question could mean several different things depending on if you are buying, building, or just looking to get started racing. I'll stick to the basic "how many hp did you gain over stock, legally building to IT specs"

Started in ITC with a stock motor rated at a whopping 72hp with a pushrod, carbed 1500cc motor. After 5 years of development, and a few wins along the way, we dyno'ed the car expecting something in the 90's considering all our work and experimenting over the years (we were running 3 of them at that point).

Our results??......... 88 natural horsepower baby!! (this was in '97 mind you) We were probably one of the top 6 fastest ITC cars in the Southeast at the time, and, (with a Pobst, or a Fowler driving..)maybe top 3.

You will get lots of different answers, so take them all in. Good luck with whatever you decide on, just remember to have fun doing it!

Mark
 
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