I notice there is not enough room to really port match in the head. has any one done this and is it really necessary.
radiod;1760937 said:Don't quote me on this, but I'm pretty sure on the exhaust side, you want the ports to be slightly smaller than the manifold diameter so the exhaust gases can expand as they travel out of the head.
IJ.;1760942 said:It's so it acts as a reversion dam.
IJ.;1618591 said:Think of it as a non return valve for the exhaust port, if the Header port is larger than the exhaust port in the head you have an effective dam.
radiod;1761229 said:That would make sense. Best to keep the flow going towards the turbo than having it try and make it's way back in to the engine. For those that might be confused still, I'll lay down an IJ quote from another thread I found...