Re: So I just ran the class final at Indy.......
 

I think you are try to slow your car down so you don,t get HP. But how big is big and how small is small.I once torn down down by Wayne Lewis and was told my carb was to small, that all that was said. You do not have a problem if your camber cc are to big or your runners are to small. Merry Christmas To all. Tom

Re: So I just ran the class final at Indy.......
 

I would think if your if your Stocker had unaltered intake or exhaust runners that CC'ed less than spec., or combustion chambers that CC'ed larger than spec it's obvious you are not grinding and bead blasting or using acid on your heads. I would also think if your carb had the right unaltered part number on it and measured smaller than spec. It left the factory that way. With either scenario IMHO it's obvious no one is trying to cheat. Correct me if I'm wrong but you are not required to run the factory lift on the camshaft in Stock, you just can't exceed it. If a Super Stock cylinder head guru finds out by putting epoxy and brass in the right places and making the runners smaller the car gets faster. If they hold less CC volume that spec. will the head get tossed. Just curious, Don Jackson

Re: So I just ran the class final at Indy.......
 

The key as my brother wrote is there is a plus and minus number for the carb. Cam lift only plus would be bad. BP

Re: So I just ran the class final at Indy.......
 

Both are out. I think

Re: So I just ran the class final at Indy.......
 

Also if you are doing your homework you are going through a pile of cores to find the biggest that stays within specs, if being told it's too small you didn't do your homework.

Re: So I just ran the class final at Indy.......
 

"plus .005 or minus .015", and "max" or "min" size, CCs, CI, lift or whatever are 2 different specs.

Numbers can be counterfeited and parts can be machined/modified.

Re: So I just ran the class final at Indy.......
 

Billy, I'm surprised at you. Surely you know that the reason specs became so important is because people were mucking with "correct part number" parts.

Re: So I just ran the class final at Indy.......
 

To answer your question Garrett, no that exact scenario has never happened to my knowledge. BUT, a close acquaintance of mine was at a Divisional race a couple of years ago and was "spot" checked. The Tech Man wanted to see his carb and he complied. The carb on his combo was the ONLY number listed for his combo and (in fact) was the original carb for the car. Tech Man measures carb, carb comes up WAY (WAY WAY) too small, Tech Man wants to know why his carb is so small. When acquaintance tells Tech Man that it is the original and correct carb, the Tech Man doesn't toss him but tells him not to come to another race with THAT carb on the car.

Now, sorry for getting long-winded but the reason I wrote this is I was having a conversation with another acquaintance of mine yesterday and one of MY combos came up. Now, said combo will run MUCH better with a smaller carb on it but the original, correct numbers carb (I have it) is a big carb. The problem is that the NHRA throttle bore and venturi spec are for the small carb.
Do I run the "correct" carb or do I run the "in-correct" carb with the smaller specs? If I use the "correct" # carb, I take the chance of being tossed for too big a carb. If I run the "correct" spec carb, I take the chance of being tossed for too small a carb. In a situation where the guide contradicts itself, I really am not sure just how the chips might fall.

Now when you're thinking of the correct answer remember, I'm the guy who was tossed at Indy once because my heads looked "too stock".

Re: So I just ran the class final at Indy.......
 

Billy, I don't see how you could have a problem if your carb meets NHRA specs. But you really should be discussing this with NHRA.

Re: So I just ran the class final at Indy.......
 

[QUOTE=Billy Nees;604497]To answer your question Garrett, no that exact scenario has never happened to my knowledge. BUT, a close acquaintance of mine was at a Divisional race a couple of years ago and was "spot" checked. The Tech Man wanted to see his carb and he complied. The carb on his combo was the ONLY number listed for his combo and (in fact) was the original carb for the car. Tech Man measures carb, carb comes up WAY (WAY WAY) too small, Tech Man wants to know why his carb is so small. When acquaintance tells Tech Man that it is the original and correct carb, the Tech Man doesn't toss him but tells him not to come to another race with THAT carb on the car.

Now, sorry for getting long-winded but the reason I wrote this is I was having a conversation with another acquaintance of mine yesterday and one of MY combos came up. Now, said combo will run MUCH better with a smaller carb on it but the original, correct numbers carb (I have it) is a big carb. The problem is that the NHRA throttle bore and venturi spec are for the small carb.
Do I run the "correct" carb or do I run the "in-correct" carb with the smaller specs? If I use the "correct" # carb, I take the chance of being tossed for too big a carb. If I run the "correct" spec carb, I take the chance of being tossed for too small a carb. In a situation where the guide contradicts itself, I really am not sure just how the chips might fall.

Now when you're thinking of the correct answer remember, I'm the guy who was tossed at Indy once because my heads looked "too stock".[/QUOTE

run the carb that the spec calls for in the nhra specifications guide ,, if you have information that can prove the correct carb along with throttle bore and venturi ,contact nhra tech official and plead your case
have both carbs on hand at your next divisional race and let them decide


I also haven't seen any +/- spec on carb bores or venturi's