i have run across 2 different Holley Sniper intakes for 102 throttle bodies at some pretty good discounts. I am building a mostly stock 5.3 but with a LS3 Cam, springs, and lifters. A 102 throttle body seems like overkill and besides, I would like to stay drive by wire. Is it possible to get adapters to put my stock throttle body on this intake? I can pick one up for about what I am seeing LS1 manifolds for and less than LS6 manifolds.

 

I'm not sure about the sniper intake but I run my stock ls2 90 mm throttle body on my fast 102.

 

Thank you for the reply. Will have to see if I can find an adapter for my TB as I am sure that it is smaller.

 

The bolt patter for 90mm and 102mm TBs should be the same......so a 90mm TB should be able to bolt onto a 102mm intake with no problem.

Only thing is that you will see zero benefit of the 102mm intake with a 90mm TB.

KW

 

manifold design isn't all about the opening. runner length, cross section, plenum volume all play a major role. if it's oversized for his app, it's because of those things, not the size of the throttle body.

 

All those Holley intakes are identical, just with a different flange up front, so there is no problem with what he proposes.

 

What he is doing should work fine.

Only thing I advice against is adapting a 78mm intake to a 90mm tb. I did this on a LS swap for a customer. The larger tb opening made so much turbulence, that it had a crazy loud whistle to it. Sounded like a procharger at idle lol.

 

Nothing you've stated is applicable to this discussion..........

But thanks all the same.

KW

 

Thats' interesting. I had always suspected opening up the LS6 intake to a 90mm throat would benefit it greatly

 

It would benefit it. But my customer ordered a 90mm tb and had a 78mm truck intake. So thin we used an adapter for it to bolt up. So basicly u have a 90mm opening reduced to a 78mm hole. To much air turbulance.

 

Oh i was thinking along the lines of epoxying a 90mm throat onto a LS6 plenum. What the LS2 intake should have been.

 

Really? There was a pretty big differnce on my ls2 going from the stock intake to the fast 102 while keeping the stock 90 mm throttle body. I didnt dyno my results but plenty on the vette forums have and 20hp+ gains are pretty typical.

 

You would've had the same performance increase if you had gone with a 90mm FAST.

Why?

Because the benefit you got was not because you went a 102mm FAST intake, it was because you went from an OEM LS2 intake to a FAST intake.

One day, when you swap in a 102mm TB.....you may see even more improvement if your setup has the ability to use the additional airflow.

KW

 

I disagree, as stated the FAST 102 Intake has improved plenum &
Runners compared to the FAST 92. A FAST 102 with a 90 or 92
MM TB will out perform a FAST 92, 90/92 TB combo on even
a modest HC combo (especially with
A velocity ring), and be easier to tune VS 102 TB. 90 MM TB
is not a significant limiter (6-8 HP) until ~ 650 HP @ Flywheel.

 

Well then I stand corrected.

KW

 

Good job, sport.