Acropora

Well I'd hope if someone could tell the difference between a turbo S and an reg tt, 450vs408hp, one could feel the 50hp this is worth.

jmreiser

I know what you mean, but it is really hard to tell when you have the delay of working on the car. Don't forget you need to remove the center section of the intake manifold from the car so you can clean it really well. It would suck to have metal shavings go into the cylinders!

You can make 408 hp just fine with the Turbo S if the weather gets hot enough, that is, it might make 440 in the morning, and 400 by noon on a hot day. The ECU starts cutting the power once the intake air temp gets above 70 degrees or whatever it is. The cutting of the power is continuous, that is, the hotter it gets, the more it cuts back.

Your example is a good one though. Let's play it out. The way to do this without a dyno is with two cars. They must be the same, ie. stock. Drive both (one right after the other) in the same conditions. Or have a second driver race you somewhere safe, not to test clutch slip, but to see how quick is each car in 6th gear from 3000 rpm to redline or whatever you can manage safely. Then modify one car and go again.

Anyway, resonance tuning is really important for non-turbos, but largely (perhaps entirely) irrelevant to forced induction (turbos). So I think the point is, you're not going to get 50 free hp by making a second hole in the intake plenum in a turbo motor where the air is coming in there already, forced under pressure. At full-throttle, on-boost, the air comes in through the throttle, is allowed out to both sides by the large hole on each side, where each side has a common chamber that pressurizes all six cylinder intake runners. Any cylinder whose intake valve is open gets filled immediately. Any left over air is welcome to go back through this second hole that we just made, to go see if any of the cylinders on the other side didn't get any. However the other side is at the same pressure, since we still have the two big holes. Talk me through it, how does this second hole make power?

I am still hoping for a dyno run of this change by itself (without any other changes). I predict close to 0 hp for this change by itself.

Also note the buttdyno will swear that almost any change makes more power. But there is hope for the doublebutt dyno method with two identical cars.

Kevin

This modification will NOT give a stock car with stock cams 50HP.. What is will do is increase the CFM or flow of air from one side of the manifold to the other. As the firing order of the engine fires between each bank the opened up chamber acts as a balance tube and allows more air to freely pass back and forth. This will not help in the lower RPM, however from 4500 and up you might gain 10HP.. It would help an engine with camshafts and ported heads.. A free flowing exhaust would also allow this mod to enhance the topend.

Acropora

"But there is hope for the doublebutt dyno method with two identical cars." LOL, jm

orleyd

Viperbob,
How do you keep you boiler room clean?

I need to sanitize mine and would appreciate your advice.

Dave

mooty

no jauder, you need a new car!

Woodster

I believe that rob at S-CARGO has been doing some form of this intake modification with very
good results. But I believe it is on very moddified motors with ball bearing turbos, cams, etc.
maybe he could tell us...
Marty K