I am doing a port and polish on my pre 98 head with the vain in the exhaust port. I did a few searhes to see if I could find the info I need. All I found that it was acceptable to remove the vain if I am running boost nothing about NA applications. Since I will be running NA with a 4-2-1 header can I remove the vain. If I did what would happen. Thx
If your running any internals to your engine such as high comp pistons or a cam then it is acceptable if you do not have any different internals done then keep the vain
Erik Packard
For N/A you want it there period. It is for scavenging. You can reduce the profile slightly, but do not fully remove it.
Just a little off the top
fortune cookie say: better a delay than a disaster
thx for the help. I have more question pertaining to lifters and springs but i will search some more to see if i can find the answers myself. Thanks again
The vane is a anti-reversion precaution taken to correct for the large exhaust-ports that have the floor drop-down dramatically (Rule of exhaust-porting: Never touch the floor!) instead of just gradually curving away from the valve towards the outlet. You can smooth it, so the gasses will flow over it smoothly one way... but leave the high-point on the end towards the port-outlet, and the face of it towards the outlet flat so it can still do it's job. Hey, it's this or look into getting someone (Cyclone?) to make an anti-reversion header for you.
Go beyond the "bolt-on".
