im sure its been talked about somewhere but i need some help based on experience or knowledge. i have the gt40x heads and holley systemax ii intake. i have the gaskets for the manifold to heads for 93-95 cobra. now my question is if those gaskets will work or do i need diffrent ones?
I had just this question the other day when addressing my own GT40X heads. It was recommended to me by one of our OHV guru's to run the Felpro 1262s3 steel core gaskets.
The Ford M9439A50 Printoseal gaskets ar junk. They were designed as a race gasket. Race gaskets are designed to be changed often. Under the duress of daily driving usage, they'll melt and shift around all over the place. The Steel Core gaskets are the only way to go for longevity and their 2.10"x1.28" ports will be more than large enough to feed your Systemax intake.
Felpro makes crappy gaskets too. They've got the paper and their own version of the printoseal, which is likely what you've run before. But their steel core gaskets are fine. Victor Reinz also makes nice gaskets. I've used them many times before with zero issue.