I've just got a 68mm RPM billet TB n very nice it is too.

My problem is I'll be runnin it with a CTR intake manifold which I want to get port matched. When a intake manifold is port matched is it best to have the flange on the intake manifold tapered out from the TB (68mm) or have it at 68mm all the way in??

Also my DC Sports DAC has a 61mm inside diameter on the part that is nearest the TB is it best to get that part cut of & a 68mm+ piece of ally pipe added?
What do other ppl run intake wise with a big TB I cant see how a DAC with it being 61mm helps

BillB

 

Ehhh..OK if your CTR manifold intake side is 6Xmm (i really have no idea what they are...i know skunk2 is 65mm) you dont need a TB too much bigger b/c you are still restricted by the IM intake side..... It would be ideal if these match...basically like a smooth bottleneck....its almost impossible to get it all the way in without machining...and yeah get rid of any 61mm restirictive crap

 

The CTR intake manifold should be 62mm. The Skunk2 manifold is listed as 64mm. Yes you should portmatch your TB to IM. It's free and easy.