Exhaust gaskets that fit SR71 heads?

I've tried a few different exhaust gaskets and so far I can't find anything that fits the SR71 heads. Everything I've tried so far has ports which are smaller than the heads. I can trim them if I have to, but I'd rather buy a set that actually fits. I looked at the specs for every exhaust gasket on the Summit site and none of them are large enough. Anyone have a part number that fits without trimming?

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AndyF wrote:I've tried a few different exhaust gaskets and so far I can't find anything that fits the SR71 heads. Everything I've tried so far has ports which are smaller than the heads. I can trim them if I have to, but I'd rather buy a set that actually fits. I looked at the specs for every exhaust gasket on the Summit site and none of them are large enough. Anyone have a part number that fits without trimming?

Be sure to use Cobra Jet gaskets, not regular size gaskets.
Whatever company manufactured the headers should have gaskets for them.

The dyno headers came from Schoenfeld and the gaskets that came with them are CJ gaskets, but they overhang into the exhaust port quite a bit.

Ive used these on P-51's and SR-71's. Very little trimming to fit. They are re-usable.

https://www.summitracing.com/parts/pte-66054?srsltid=AfmBOooGEgiDPUMuNKeUjs3TmCpIQPDaxE88RXdRSTkTpDGoKANefGk2