real82it

So, if you check out my sig you can see what mods I have done to my car....I am wondering if I really should install a 58mm throttle body or if I am wasting my time.

-Will a larger TB improve driveability?
-Will I experience any significant power gains?
-Is there a mathematical way to evaluate my TB needs?

I have read numerous posts - some suggest yes due to my displacement and cam - then some say no due to the fact i am running forced induction.

Just looking for some input from those with experience. Thx.

NemeSS

iTrader: (127)

PP AND Summit have a decent 58mm,
u need it more than a bolt ons' car for sure

Teal94Z

yeah you should get one since you have a supercharged 383

real82it

just to close with this one.....i went with the summit 58mm TB - got to tell you I was very surprised at the difference I could actually feel in throttle response.

I had decided to go with professional products, but they are out of stock and I can only order from one place i found on the internet that has them in stock - and their return fee is too high in case I didn't like it.

Weird as it may seem, the surging i was getting around 1500-2000 rpm while cruising is significantly reduced....but unsure as to why. I was getting ready to figure out how to tune this out....but now it is insignificant enough I don't think I will mess with it.

I had the standard throttle return issues that folks have complained about - had to add an extra spring to get the throttle to consistently return to 0% TPS - you would think that after 2yrs of folks complaining about this summit and their supplier would fix it.

I am having some idle issues with the TB and have tried to tune them out.....but I think I will eventually have to do the mods posted out there about these type of TBs - drill the pass through hole and isolate the IAC passage at the rear of the TB - but otherwise pretty happy.


Final numbers - 449 RWHP, 468 RWTQ - good enough for now.

imnotplutonium

iTrader: (4)

nice numbers, nice car

Ponyhntr

iTrader: (9)

What kind of power did your car make before? Just curious what the gain was.

I'm still running the stock TB on my setup (along with a STOCK LT4 intake and SLP 2OTL), and it's making 660 rwhp and runs 10.50's at 135 mph.

I don't think big throttle bodies are nearly as critical on Forced Induction as they are on NA setups.

Counted Out

iTrader: (6)

Can't you only port the stock ones to 52MM?

If so, any write ups on doing so?

96capricemgr

iTrader: (1)

Not as simple as just opening up the holes, need to make new plates to close those holes.