Ported 4G93T Inlet Manifold

For those of you out there running big cams and a ported cylinder head, moving to a Mitsubishi Lancer GSR CD5A - 4G93T engine inlet manifold will give you slightly more top end. This is due to the shorter runner configuration on the 93T's inlet manifold. Picture below of the 93T inlet manifold. I bought the inlet manifold used from Ralliart Australia way back when this was a relatively unknown mod. To get the like new finish you have to brush the inlet manifold with a steel brush and use lots a engine degreaser/cleaner

Apart from the shorter runners the 93T inlet manifold is also lighter (did not have the opportunity to weight both manifolds but my hand carry weighing scale definitely indicates the 93T to be way lighter) than the 93P and does not have EGR (Exhaust Gas Recirculation). You can find out more about EGR in MrFixit's web page. Now unless you're a greenie (which you probably aren't if you run big overlap cams) EGR is a definite no-no for highly modded and forced induction engines.

I've also decided to port the flange entry and exit points of my 93T inlet manifold to accomodate the larger 60mm throttle body I'm using and also to fit the huge ported inlet ports on my Matspeed 93T RS cylinder head. Picture below of my 93T inlet manifold's ported throttle body inlet flange

Picture of the ported outlet flange

I was initially worried that the extensive porting might cause some low end powerband losses but happily my concerns were unfounded. This is probably due to the efficiency of the Matspeed race ported cylinder head requiring the increased in volume of air. Butt dyno indicates gains everywhere along the rev range. No kidding! Picture below shows the stock 93P inlet manifold vs ported 93T inlet manifold.

Installation was a no brainer and took bout an hour. Do make sure to plumb the vacuum hoses correctly. This is probably as far as you can go with a single plenum inlet manifold though I've seen the Honda B series inlet manifold fitted to our 93P I kid you not. The next step for me would be individual throttles. Stay tuned...