BlackBirds

iTrader: (24)

Is there a such thing as too big of an intake manifold? I've got an '02 Trans Am with full bolt ons and a TR224 cam and I was wondering if the 102mm Fast intake and TB are "too big" for a stock displacement LS1, or if there's no such thing as too big when it comes to intake air-flow.

Thanks

AznMuscle

iTrader: (7)

Too big, no. Not efficent for your money spent, yes. The intake can only give as much air as the heads can bring in. Its all in the set up also though. From many of the people running the 224/224 I have seen around here, the ls6 is fine. For my big *** cam I want the 102 though, since past 6400 the ls6 starts dropping off.

MonmouthCtyLS7

iTrader: (6)

What he said

BlackBirds

iTrader: (24)

yeah that makes complete sense for a car with stock heads, however aftermarket heads are in the near future.

I've got another question now, do the stock heads restrict flow more than the LS6 intake, or the other way around? For a FAST intake and TB it'll cost about the same as heads, so which is a better to do first.

Darkman

iTrader: (2)

LS6 (243) heads and an LS6 intake manifold are pretty closely matched at full lift (0.550 -0.600) flow rates. But aftermarket heads improve flow at the lower lift levels, which the LS6 manifold can already handle. Logic suggests to change heads first for immediate power.

BlackBirds

iTrader: (24)

ok great, makes perfect sense. thanks for the input guys, you've been a lot of help.

AznMuscle

iTrader: (7)

For your set up, I would also agree heads first, then fast intake later. I am running a 242/248 111 lsa, spinning 7k+, so for me, (honestly both would be more than ideal), the Fast would be a nice jump for me. I also want to do a lot of work to my heads to gain full advantage of my cam and FAST set up, so...more money and time invested.

Musthaveboost

102 mm seems huge. Wonr their be a power loss down low over say a 92 mm??

airforcemanss

iTrader: (23)

go with a 90/92 tb and a 102 intake. the smaller tb will be easier to tune and there will be no gains if you go to a 102 unless your doing a stroker down the road (4xxci)

SweetS10V8

iTrader: (4)

No, The runner design creates its velocity and is what dictates too big, too small, just right. The throttle body opening is just an air bleed to the plenum.

Musthaveboost

Will their be a HP/TQ loss in the lower RPM's? Thats the primary thing im worried about.

BlackBirds

iTrader: (24)

That's what I was originally concerned about as well. Anyone with an answer?

Tony Mamo @ AFR

iTrader: (13)

NO.....the size of the TB opening is a mute point. Its more advertising than anything else. The runner shape and length and plenum volume are the three biigest factors when it comes to manifold design.

Not to mention we arent discussing applications dealing with carbs where BIG can mean poor airspeed and improper fuel atomization in regards to a discussion dealing with manifolds. A TB is basically an adjustable airblade....thats really all it is.....a carb on the other hand is altogether different as it meters fuel and therefore being properly sized to the application is a much more important scenario.

Hitting on the OP's concerns.....always go heads first than a better intake manifold. Without a really good head a higher flowing intake wont really shine.....for that to happen the stock intake must become a restriction as it certainly does when you place an efficient set of deep breathing heads underneath it.

You would see a little gain in power swapping the intake first but your better off getting heads first and/or doing them at the same time money permitting.

-Tony

AznMuscle

iTrader: (7)

And the master himself has spoken...