Does anyone have any actual dyno results that prove 52mm TB's are a better choice than 58mm TB's with ported heads, cam, bolt-ons...?

Thanks!

 

I love my 58mm.. I think 54mm is ideal but the price isn't.

 

Yeah I have a few buddies that are running 58mm TB's and love them, but then I hear how they're pointless unless you have something like a blower....

That's why I'm looking for dyno sheets.....

 

For the mods you have in your sig I would recommend against going with a larger TB. I have also heard of people losing hp when going with larger TBs so be careful. I am running a 52 mm TB on my blower setup. I believe that the guys at Combination Motorsports are still running a 48 mm tb on their monster Impala. A larger TB will be more crucial on a NA than a forced induction motor.

 

This seems to be the general concurrence that this board exemplifies. Anyone with actual dyno info that proves that a 58mm TB is actually not smart? Anyone with dyno info either way?

 

I have a 58mm Edlebrock TB on my SS, the intake is ported and matched. My other mods consist of:
SLP Ram air CAI, Granatelli maf, G2 high flow air bellow, SLP air temp sensor, Crane Gold Series rr's 1.6 ratio, LT4 valve springs, Hooker Super comp Long Tubes, Mufflex off road Y-pipe, Cats! smog! EGR! SLP 3 inch catback 2OTL, 160* thermostat, homemade cooling fan mod, TB by pass, SLP steel billet flywheel, Spec stage 3 clutch (carbon) 1le panhard, poly torque arm mount, 1le drive shaft.
I put down 297rwhp, 315-316 ftlb's torque. A/F was 13.5 all the way across the chart at wide open throttle, if I could bring that down to 12.8 or so, I could see 300+ at the wheels. don't know if the 58mm TB helped, but I could tell you right now it definantly didn't hurt anything.

 

I think "Injuneer" had a link to a post where a guy didn't gain anything from a 58mm TB. You might want to PM him.

 

Thanks!

 

There is a guy on our state board that put a Holley 58MM TB on a bolt on LT1 car. He LOST about 12 RWHP from it!!! Now if he wouldve had a cam, rr's, and some head work or something it wouldve probably picked him up some hp. He even posted the dyno sheet so we could all see. Put it this way, he was highly pissed.

 

might want to check out this thread
http://web.camaross.com/forums/showt...hreadid=148041

i think there are two points that can be made, then the decision to upgrade is up to you.
one, going to a larger throttle body is a poor choice as far as hp per $ is concerned. i think that is a very real arguement against it cause putting the money in other mods would yield better gains.

second, you will lose/gain next to nothing when stock and your gains will be proportional to the output of your engine. in other words, the more power the engine makes, the more it can benefit from a larger throttle body. for what it's worth, i picked up 8hp 12 ft-lbs while making slightly less than 400 hp at the rear wheels. had i made the swap after other mods putting me at 470 rwhp, i would have seen even larger gains.

JB

 

I'd hope we all knew that you had to open up the stock intake to 58mm before adding a 58mm TB...

 

When I did my cam swap we pulled the intake off and hogged it out.

 

For what's is worth I'm making almost 400rwhp with my stock 48mm TB and high stall A4

 

I was talking to Phil @ AI (The porter formerly known as Skarodom ), he reccomended a 58mm for my application (383, full ports, long tubes etc.). He said it should be worth 10-15 HP.

Still don't know if I want to get one yet, I need to figure out which brand first.

So you might be able to pick up 10-13 HP with a larger TB then maybe? Have you done it yet?