58mm throttlebody good for a bolt-on car?
 

Car has LS1 Lid conversion w/ granatelli lid/k&n filter, ture duals with hooker midlengths, 1.6rr.

What I am mainly looking for is better throttle response more than hp. I know some report better response with the bigger tb's but what about on a bolt on car? Thoughts with the ls1 lid?

Second question should I descreen the maf with the ls1 lid conversion if I am getting it tuned by pcm4less?

Its overkill IMO, you dont really need to go bigger unless your going with a power adder or get into the h/c territory.

Well feel free to argue but a 58mm would be to much fo nothing.A good 52 mm would be fair enough and would give you a better throttle response.

The screen of the mass air flow is only usefull at idle.It smooth out the air so that you can have a clear idle.But when your running it act like a small restriction.I would take it off.

Spend your money elsewhere, or just give it to me! :D

Do not remove the MAF "screen"..... its there to provide "smoothing" of the air flow under both laminar and turbulent flow conditions. It does not provide a significant flow obstruction. You will do more damage by screwing up the MAF sensor calibration when you remove the screen.

Thanks Fred. I'll leave it on in that case.

Any throttle response difference between a 52mm and a 58mm on a bolt on car? I will port the intake for 58mm if it seems at all worthwhile. For just the added throttle response I would do it but not if I am going to bog or lose power. Any bog w/ the 52mm?

Well it seems that im totally off the track sorry... i ve learn something today ;)

When I had my engine on the engine dyno, we were able to measure air flow vs. throttle position, with my 58mm Holley TB. The engine made max power (a shade under 500HP) with the blades on the 58mm TB only 77% open. Opening the blades farther did not increase power. Playing with numbers, that would suggest that I would have been right on the edge of maxing out a 52mm TB, at 500 flywheel HP.

Throttle response is GREATLY changed with a 58mm. Put it this way where cruise TPS used too be 12% it is now more like 6%.

I don't know what you're talking about. All the LT1 tuners that I have talked to told me to remove MAF screen because a lot of the LT1s came from the factory running a little rich. By taking out the screen, it helps lean the car up a little bit to help it gain a little more HP. Maybe you got one that was already leaned out. You can check out GM high tech. I believe it was June of last year, they did an entire article on cheap LT1 mods. One of the first suggestions was removing the MAF screen. Now on an LS1, I have heard tuners say that you should leave it in.:) :)

Yes you can lean it out slightly by pulling the screen BUT if the tuning is right you do not need to lean it out anymore.

What exactly do you think is so different between the LT1 and LS1 MAFs where you believe it is good too descreen one and not the other???

The size of the MAF....

They still function the same and I believe some of the LS1 cars got the same MAF as the LT1.

Guess this comes down too do you understand how they function?

All I know is that every tuner I've ever talked to said that removing the MAF screen was a good thing for the LT1s, but not for the LS1s. I read the article that GM high tech put out, and I believe it was called "putting your LT1 deep into the 13s with basic bolt-ons". I did everything that they recommended, including removing the screen and my car ran 13.49@106 in the 1/4 mile. I think the LS1 intake, different type of throttle body, and/or the size of the MAF sensor has something to do with not removing the screen on the LS1.

I would go with the 52mm TB