plenum mods

Gidday evry 1,

just wondering if any one has modified their plenum chamber before?
Im talking about moving the throttle body to the front of the chamber to reduce the inlet pipe from a FMIC, hence, reducing lag.

Has anybody done this before? any problems? what are the power/response improvements?

Cheers guys.


BOYFUSION, aka, 'sideways'n'style'

Although I havnt performed the operation myself, I have been doing heaps of research on plenums, intakes and throttle bodies.

As far as I can tell, the actual engine response improvement from mounting the throttle body on the front end of the plenum isnt incredibly significant.. but it helps, makes the engine bay way neater and makes piping much easier. Theres a company around... buggered if I can remember but I could find out.. that sell stock plenums that have been modified to have the throttle body bolt on to the front. cant imagine they'd be too expensive.

Personally, I'll be getting a nice little unit from sub zero performance in aust. $1000 AUD gets you a 5.8l plenum, nicely flowed intake manifold, 68mm (or is it 62?) throttle body (I think its the XF falcon item) and a fuel rail.

Unless you guys are aiming for 600-700hp in your cars modifing your plenum chamber is a waste of time there so many other things you could do with the motor first. I am getting 550hp with stock plenum. The motor is rb30 with rb25 topend ported and flowed this is where its going to make the diffrence.