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Discussion Starter · #1 ·
This question is mostly for Bob Denard, but every one feel free to chime in.

How much rear wheel HP do you think is necessary to be competetive in an ITB Manta/Ascona (besides as much as possible)?

What do you think of the torque characteristics of the 1.9 CIH engine in IT trim?

What is the output of your ITB engines in case I want to pony up for one of your builds in the future?
 

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To paraphrase (plagiarize) Mark Twain and Benjamin Disraeli... when it comes to HP claims there are two kinds of claims... "lies and damn lies".

How much HP does it take to win in ITB... or any class for that matter? To tell you the truth, I don't know. I know what other people claim but for the most part I don't believe them. The problem is that if an engine builder tells the truth, they will go out of business. So there is an ever escalating battle of claims.

Next is some guy tells you that he had his car on a dyno and it showed 10000000 HP... he's even got the dyno sheet to prove it. The problem is that every dyno operator in the world wants their customers to come back. So, to make them go away happy, they "tweak" the calibration on their dynos.

A little story. Until last March I shared a shop with a business that had a chassis dyno. When I was building a "National" Z-car engine I put it on the dyno, made a couple of runs and decide I needed more cam... I wanted about 20 HP more and would give up power band. So, I got another custom grind cam and a couple of weeks later put the car back on the dyno. Wow was I happy to get another 115 HP!!! Well, I thought I was doing something wrong so I called over the dyno owner to check me out. He opened up the "calibration menu" and took out about 100 HP worth. He had a customer and had worked on his car for about 6 hours and couldn't gain any HP. So in order to be able to charge his customer... this goes into the category of damn lies. (Worse yet, when I zeroed out all the other "calibration" he had dialed in, I had less HP than before. So, that engine dynoed anywhere from 156 HP to 260 HP.

So back to the original question... what does it take to win? Another big factor is where you race. In some regions, the level of prep that you go up against is lower or higher than others. NASA (the race organization not the space folks) guys come to Willow Springs and tell stories about how fast they were going in their ITS cars (NASA's equivalent is P1). They even brag about turning 1:41s. An ITS in this SCCA region won't brag until they get down to 1:36s. (My last ITB turned 139's). So this part of the answer is it depends on where you race.

One truth I have learned in racing. You can't "give up" anything. No matter where you race, there is going to be a person who is going to show up sooner or later and has prep'ed his/her car to get everything out of it the rules allow (and maybe some the rules don't allow). If they are a good driver, you will be an also ran unless you too have done everything you can to optimize the car.

I think that part of your question was aimed at how much HP do my engines make. Well... I used to play the HP game. As soon as I made a claim, someone else would claim 5 HP more. So, I keep it simple... I make no claims... I let the race results speak for themselves. 5 ITB championships... so either I'm one hell of an engine builder, one hell of a race driver or both... I'll take both.
 

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Yea. I wondered that too... until I went to other regions and brought home with me my competitors doors.

And I'll take this as a chance to brag on other Opel stuff... 2 F-Production Championships... 5 wins out of 8 races in GT4 (over 2 seasons).

And in GT-2 (not me as the driver), 2 Championships

And counting.
 

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Discussion Starter · #5 ·
Somehow I knew you would give that type of answer.

I have been used many different dyno's and each has had different results on the same car. Some closer to the truth than others.

I have been using the same dyno for 2 years now. I have the unit calibrated before each session and the results are repeatable and my changes can be tracked to my satisfaction. That being said If I were to go to another dyno and have it calibrated the output numbers will most likely not match the previous dyno. I am sure the difference will be a small percentage, however I do not believe you can go from dyno to dyno and expect to compare the results.

What I was asking for Bob was a ballpark I am sure you have dyno'd your car and was hoping for a round number. This may not be the forum to do this. Maybe you could e-mail me and we could continue this discussion?
 

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Hummm. Well, let's see. We make 145+ rear wheel HP at our 2400 ft altitude. Yea, that's the ticket. We attribute our exceptional HP to two things. Hummmm The first is we have designed a special air filter box that incorporates one of those "swirl thingies" positioned vertically in the inlet tract. The "swirl thingie" part of the air filter box is in the location of the original Opel GT air cleaner. We got about 17 HP from our "swirl thingie" air box. Yea, that's it. Hummmmm. The second thing is that we rub peanut butter into our cylinder walls just before final assembly of the short block. That gives us a super seal between the piston rings and the cylinder walls. That was good for another 15 HP. Now... before everyone goes out and buys peanut butter or the "swirl thingies", go back and re-read the first paragraph of my first reply to this thread.

So, sorry, I simply refuse to play the HP "game"... privately or publicly. I simply let the results stand for themselves.

WHER DID THE SPEL CHEKER GO
 
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