I'm using a D-port gasket for my oval shaped Jet Hot headers. I need to know if i should be using an oval gasket or a D-port gasket. here are some pics my old heads and the gaskets that were used, current gaskets too.

 

Dport gaskets is what you need and should be fine, but you got some serious exhaust leaks on the bottom of the primaries and I'd suggest doubling up a pair or felpros or going with some Percy crush aluminum gaskets. Lots of guys suggest doubling up gaskets to give you a better seat. Have you checked your flange on the headers to make sure it's not bent or uneven on those?

 

All of the ports on that side show leakage. Somethings wrong for sure. It shouldn't be the gasket I wouldn't think. That's like something wasn't allowing the flange to sit flush as it was tightened down. Either direct interference in between or some sort of interference down the header/manifold.

 

If the flange is straight and the bolts were tightened from the inside-out you should really only need one gasket. I recommend the Felpro 1406s. Never once have I had a leak with them.

It also looks like you've got some serious build-up on the gasket surface, so be sure to hit it LIGHTLY with some fine grit sandpaper.

I should also mention that in some instances, doubling up header gaskets can PROMOTE leaks.

 

thanks guys,

ill be taking the motor out in a few months and ill check to see if the flange is straight. there is signs of a leak but no sound of a leak. i probably did not tighten form the center out.

 

I could be way off base but it looks like that gasket isn't even big enough to cover the bottom of the opening of the header tubes and isn't even touching the flange on the bottom side in the middle! Also good to check the bolts again after a couple of drives.

 

I'll check that too when i pull the motor.