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Header options for a '90 XJ

Oldiron90

NAXJA Forum User
Location
Colorado
Looking to replace the stock manifold on the 4.0 in my '90 XJ.

99% of the header options I've seen are for '91 and newer XJ's...

I was reading through a pretty in-depth thread about "The Best Header" and it seems like Gibson won the vote in that thread.

Is there any reason I wouldn't be able to slap a Gibson header for a '91 + XJ onto my '90 XJ 4.0?

Do I need to swap to a newer style intake manifold to make this happen?
 
The bottom of the manifold is unlikely to fit your cross over pipe. Even if the manifold clears your intake and has a CO2 sensor bung.
If your stock manifold isn't cracked I wouldn't mess with it. IMO any horsepower gain is going to be negligible.
Both Rockauto and Morris have a stock replacement, that look identical to me. Rockauto is cheaper.
I'm more picky about the gasket, OEM is IMO the best, FEL PRO is good. Some of the gaskets that come with a budget manifold look questionable to me.
 
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