I have the Percy gaskets, the header to head flange is not the issue, it is the angle of the exhaust to header lower flange angle that is slightly different. Not a big deal, should not take more than an hour a side to cut and reweld.


Bill S.

It is actually the collector gaskets that I am having the issue with.

Then your exhaust flange made need to be cut off (not on the header) and rewelded to match the angle of the collector side of the header. Again, not difficult to do, about an hours worth of work per side for a competent shop. I won't have time to take it to the shop for at least a week or two. When I do I'll see if they will allow me to take some pictures as the job progresses.


Bill S.

He standardized it. I ran into this problem as well a few years ago when I tried to bolt up the exhaust from my second build (owner "lent" it to me in exchange for some work) onto my third build to get it to the exhaust shop. All headers from the last few years should be interchangeable but ones before that may or may not be.

I use the Percy ones and a bunch of red, sensor safe silicone on the head side and a good felpro and silicone on the collector end. I had very bad luck using the Percy gaskets on the collector. They simply deformed and leaked after about a week.
Before switching over to this procedure I had to redo the header gaskets every year. I haven't touched these since I wrapped my headers 3 years and 15K miles ago.

-Jason

Just in case anyone is interested to learn the fate of this Monster, I bought it from Bill in February and drove it from PA to Florida where it spends most of its time in my garage. I drive it a few times a week. What a blast!

Wait, you actually drive it :rofl:


Bill S. :yippee: