Now, i used to run on a 2.8 vr6. i bought a 2.9 engine (recently rebuilt) to put instead and i wonder what intake manifold is better to use. i've heard some things about 2.9 engine with 2.8 intake being the best combination. does anyone know more about this or anyone tryed this? left-2.8, right-2.9 manifold:
that sounds logic, but bigger ports may also cause less speed for the air. a friend of mine read some years ago about 2.9 manifold causing a weakness somewhere around 3000rpm. sadly he doesn't remember what forum that was and i couldn't find anything about this subject, most of the guys are trying to make 2.9 manifold clones for their 2.8s and to be honest i have a feeling that doesn't improve anything. but the 2.9 engine with 2.8 manifold could be something. nobody here tried that? come on guys, i need to know which manifold should i choose for polishing work =))
You didn't mentioned anything about port & polish before... If you're gonna port & polish the intake then I'm almost sure that it doesn't matter which one you use. Your best bet would be to post a thread (your guestion) on VWVortex in the VR6 technical forum. Good luck
what i meant by polishing was for the outside, just for the look. i will try to find answers there ass well. anyway if there's somebody that experienced that, this thread is also open. technical info's allways welcome.
16v_DUB
Tornado
If you're gonna port & polish the intake then I'm almost sure that it doesn't matter which one you use. Your best bet would be to post a thread (your guestion) on VWVortex in the VR6 technical forum. Good luck 
Bozo
pikske