Headers for an AMC 258 cu in I6

[JavaJeep]

I need some advice on building some headers for the 258 cu in straight 6cyl in my 1980 Jeep J20

The firing order is 1-5-3-6-2-4

I want to group the headers into a 3 into 1 system , the question is do I group cyls 1 to 3 and 4 to 6 or group using the firing order or what ?

[tgreese]

Originally Posted by JavaJeep

I need some advice on building some headers for the 258 cu in straight 6cyl in my 1980 Jeep J20

The firing order is 1-5-3-6-2-4

I want to group the headers into a 3 into 1 system , the question is do I group cyls 1 to 3 and 4 to 6 or group using the firing order or what ?

I think you want the exhaust pulses to be evenly spaced in each group, so two groups, every other pulse would be 1-3-2 and 5-6-4; that's 1-3 and 4-6, like you said.

[Tonka J200]

I have a header on my 230 OHC six and it is 1-3 and 4-6 (firing order is 1-5-3-6-2-4). I then have duals going back to a 2-in-2-out muffler (Magnaflow), with duals exiting together behind the rear wheel. It woke up the engine a little and it sounds great!