Anyone know what CFM a TPI set up will flow? I know that a 48mm TB will move about 780 CFM, but was wondering about the 52mm and 58mm. Thanks.

 

i would guess the 52mm TB would flow about:845
and the 58mm TB would flow about:943

 

Does it go up linearly like that? I mean, diameter (well radius) to area grows exponentially.

 

not sure, probably not, because of aerodynamics and other bullocks like that. but like i said, its a guess, and an educated guess at that

 

someone had posted up what the different TBs flowed, a 48 with an airfoil showed to flow more than a 52 without an airfoil.
a search may turn it up.

 

but the aftermarket TB's have a molded air foil

 

opps, i was wrong about that, the 52 without an airfoil does flow more than a 48 with an airfoil. i knew i should have looked it up first.

https://www.thirdgen.org/techbb2/sho...hlight=airfoil

i put a 52 on a customers' car a few months back & it didn't come with an airfoil. it looked just like the stock one but with bigger plates.

 

what company provides TB's that dont have that molded in airfoil? unless your speaking of modified stock ones?

 

i don't know where he got it from,.. i think from comp sales.

*EDIT*
i went over & looked at jegs, your right, they all have it molded in, i think the guy got ripped, i remember he said he paid $300.00 for it.

 

i do know some places that could bore and repin a bigger blade, but that is quite uncommon.

 

I had a friend bore my stock TB to 52mm. I used TB blades from two GM 3.3L V6 throttle bodies.

 

Its becoming more common for LS1 guys to port theirs.

 

So wait, if I were to put a TPI setup on my 412 sbc with a 48mm TB it would be "better" than my 750 cfm holley carb? Would I lose power doing this? I mean if they flow the same? Or is it that TPI doesn't inject enough fuel or something?

 

Codename 47, if your asking about the factory TPI intakes of the 80s' up to 92, the TB can flow ok, but the rest of the intake can't flow for crap above around 4500 RPM. you would probably have some killer low end torque with that 412 though, but nothing up high.
if you want to go back to a FI setup, either a converted LT1 or a aftermarket intake is the way to go.
i kind of like the way a FIRST Injections TPI intake looks.

 

Hehe I wish I had the money to do that :P. Thanks for the info!

 

http://dtcc.cz28.com/flow/index.htm

Here are some flow numbers of various TPI parts.

 

yeah, I personally really like the FIRST set-up, but for 412 inches...? I'd be thinking more like ported HSR. I've been thinking about going back to FI, but w/ a custom hand-built intake just to be different. My new motor is going to be a 380 de-stroker(4.155 bore, 3.50 stroke) probably going to turn some where around 8200 r's. bottom line, a TPI intake is never gonna breath enough. Yes, the TB flows over 750 cfm, but the intake doesn't...in fact, it doesn't even come close....

 

Thats an exact answer to my question. I like my carb for now, I wasn't planning on using TPI, I was just throwing it out there for examples sake.

 

My BBK 58mm TB didnt have an airfoil. Got it for cheap and the TPI is still stock, so not like its making a difference anyway. The TB will eventually make its way into my HSR build so hopefully that will make the mod more worthwhile.

If you want EFI with a carb style intake consider converting to singleplane EFI w/ a 1000cfm 4bbl TB. Its basically a carb style Intake Manifold with a TB on top instead of a carb and injector bungs drilled into the manifold. Sweetness.

 

Before I bought my Holley 58mm, I called them, and Holley told me that it flows ~1050 cfm.

 

How old is it? Mine has one, its part of the casting.

 

As does my 58 mm BBK TB....
Ooops, you didnt read that Vince

 

I'm not sure how old it is. Would the numbers on the TB help any?