3 replies to this topic

[coopermpi]

Does anybody know the size of a standard throttle body on an MPI, and will a k&n foam type filter still fit on a uprated one?

Thanks

[nicksuth]

Standard is 48mm dia and uprated is 52mm dia. These dimensions refer to the butterfly diameter so the top section that the filter fits to is same on both.

[coopermpi]

thought so..... have you got round to yours yet, i want to know some more stats and info before i buy 1.

[nicksuth]

Yeh, fitted mine (52mm) the other week along with a new K&N Cone Filter and while it still needs to go on to the rollers for setting up etc. it does make the engine more responsive. The K&N also makes it a bit noisier (induction growl !!)

The most noticeable improvement was when I fitted an Adjustable Fuel Regulator (Power Boost Valve) and at the same time fitted reconditioned (cleaned/calibrated) Injectors.

To be honest, I have replace so many parts it's difficult to know which has actually cured my misfire? The engine still hesitates (but everso slighly) when you try to feather the throttle above 3,000 rpm but that may just be the sporty cam not liking steady running?