Post by
HeavyDuty »
https://forums.nicoclub.com/heavyduty-u10182.html
Sat Sep 27, 2003 10:32 am
Stock Nissan OEM 300TT cat gaskets, they have an elliptical 'V' channel to the sealing surfaces, two layers per gasket, IIRC.
The ID of the hole is more like 2.25, which is more like your HS header & cat inlet, right? (Just the distance between the holes is 2.5", but the opening is smaller) Big a$$ flange, small hole.
Buy one & try it, if it doesn't work, I'll buy it from you, I use them all the time on many different applications.
Also, if it's a Random Tech high flow, you'll need to weld the floating flange in its' correct orientation (from the back side of the flange) for a total seal irrespective of the gasket. Too hard to perfectly center the gasket on the protruding lip of the cat stub itself.
If it's a non-floating flange, then go for it.