ttAmerica RoadsterAWD

Todd K at Protomotive told me that he has seen 50 extra HP at around 7000rpm by "knocking out the resonance chamber on the center section of the intake manifold on 993tt". He says that in stock form, HP tends to roll off rather quickly. Since I don't have titanium rods etc., thought somebody may want to know this and maybe benefit from it. Guess I've got to say YMMV, not affiliated etc., Hell, I don't even know what chamber he's talking about.

Jaime

Kevin

ViperBob posted a thread about it a few months back.. Most stock engines with stock turbo's run out of steam before 7K

viperbob

Jaime,

Here is the thread

https://rennlist.com/forums/993-turbo-forum/186906-while-i-had-my-car-apart.html

ttAmerica RoadsterAWD

Duh, so that's the resonance chamber!! Ok, nevermind.

Jaime

Jean

In fact , it is about the manifold, not the TB. The N/A manifold has the lower resonance chamber
open, so it makes great top end power. The factory tt manifold is blocked off down there, picking up midrange torque, but not gaining the top end power available when it's opened. The TT manifold does not have the ability to have the flap that will allow both conditions to exist. So, basically you have to make up your mind as to which is more important, midrange torque, or top end power. Typically, on these types of engines, we have soooo much midrange available with all that boost that losing a little bit in there isn't as big a deal as maintaining more power under the curve on the top end.

I have used the N/A manifold on my engine, which explains a little (besides the size of the turbos) lower midrange torque than say a standard FVD K24 based engine. It is about choices.

To have this work, you need to have turbos that will take you up there and engine internals that will let you see above 7k RPMs without risk of failure, and that includes rods. An engine that revs beyond 7K RPMs in itself will let you see more HP, provided the turbos follow, and if they do, then the N/A Manifold will help. This has been tested on engine dynos and the 50HP gains mightr have been seen as a result of increased RPMs AND this particular modification AND larger turbos flowing up there.

This would be my interpretation of the above.

K24madness

Mine has been opened as well as a larger throttle body and a intake splitter. Maybe that helps explain my good top end.