Just wondering does anyone use a different throttle body other than the kr type with the two butterfly valves? I know I can port the existing one but want to know my other options. I like to try a larger throttle body. I'm running a 2.0L 16v ACE with KR pp head and cams (175bhp). I would be interested to here of anyone with experience of the mk3 16v one (if different) and the VR6 one. Thanks for your help.
VR6 TB uses the same size butterfly as ABF...in a larger casting, which is none too easy to physically fit where a 16v TB goes...so no advantage there. VR6/ABF TBs seem to be good for 220+ BHP (on a VR6 anyway...amybe the ABF manifold restricts before that?) so I wouldn't have thought an ABF TB would be a bad option. As for larger again cable operated TBs...I'm not sure. There must be plenty available.
there's a webber one that fits the 16v and has one single large butterfly, or I believe there's a 924 or audi one that might fit and is similar, but TBH I don't think it's worth bothering, it's not the restriction on the 16v anyway and the single large butterflys can make the K-jet engines very ON/OFF and difficult to drive in traffic.
If the t/b has the same dimensions as a vr6 item then I'd concentrate on perhaps some flow work to the inlet manifold (50mm?) and serious airbox modification. I have personally removed most of the outboard lower half of mine. A well modded airbox definitely makes a power difference having seen before/after evidence at TSR.
the MK3 16v/vr6 is very different in terms of shape, MK2 tb hole is rectangular and mk3 is square. you'll need to either chop and weld the inlet to make the hole bigger or fit some kind of adaptor cone
