Whats the deal with 4.0 headers? 91-94, 95-97, 98-01??

[inh]

I'm trying to find some affordable headers for my 2000 4.0 OHV, mostly because I want to lose three of the four cats, and replace the 4th with a high flow. There are plenty of headers for the 91-94, im guessing the 95-97 have a different EGR setup, which makes sense, but is 98-01 really that much different, or perhaps they are thinking for the SOHC engine and in reality a 95-97 header would fit my OHV engine fine?

 

[IZwack]

For one thing, the exhaust lobes/bolt pattern on the heads are different (between the two blocks) because I had to send the guy a new set of gaskets to trace from in order to laser cut some header flanges.

 

[inh]

Well crap, that sucks =[ Are you making some 98-01 headers IZ?

 

[IZwack]

Well crap, that sucks =[ Are you making some 98-01 headers IZ?

Yeah but its for the SOHC and wont be compatible with the stock exhaust cauz it crosses over on top of the trans (as opposed to running under on the stock SOHC and OHV config).

 

[inh]

Well, after further research, it looks like the right side is the same part for a 94 and 96 truck, but the left sides are different, so I'm guessing different EGR port location. An '00 truck has completely different heads all together.

I might just have to suck it up and get some headers without a Y pipe..

 

[IZwack]

Well if its only the EGR thats different, then you might be able to move the EGR port to wherever you need it - just cut the EGR port, fill up the old hole, cut a new hole and weld in the EGR port.