Just bought a used header and exhaust. It came with the gaskets and I noticed that the gasket covers one small hole out of 2 for each gasket . But which hole is it suppose to cover because if you flip them over they cover the other one.


So basically it looks like this


| . || . |
| o || o |<-- top bolts_______________________ 0
| () || () |_____________________________________/ \
| . || . |____________________________________| ( ) |<--- ugly version of gasket
|o o||o o|<- holes being covered_______hole-->\o /
| o || o |<- bottom bolts_____________________0


Should the holes on the gaskets line up with the two inner holes or the outer holes? Or does it matter?

Sorry if this is a simple question

 

IIRC from when I had my own RB header/presilencer and had them on and off the car a few times the holes were for some emissions bs that ran through the stock log manifold. So the holes in question aren't really in use with the RB header (the mounting plate covers those holes regardless).

 

Gotcha. Kinda figured the header was covering them but just wanted to make sure. Thanks for the input.

 

What year car? You flip it over to cover the rear small half inch hole. The front small half inch hole is not used and goes nowhere. Series four non turbo.

Or another way to put it............the stk exhaust manifold had but one small half inch hole and that hole lead into the rear exhast port on the Manifold. That is the one you want to cover up. It's called the EGR feed hole on a series four non turbo car. IF you don't have a non turbo series four..........shoulda said so.