Opinions on Headers

[TheWeekendWagon]

First off, I know there are some threads on headers here but they're all super old so I want to start a new one for current info as many times products change over time.

As far as I can see there are 3 options for headers on the market. Doug Thorley, Headman, and Patriot...

Doug Thorley: Does anyone have these with the Y-Pipe that BJ's Off-Road sells? I have heard this setup hangs down way below the trans crossmember...true? Any photos here would be GREATLY appreciated. I have a '90 GW so the later model Y-Pipe.

Headman: Any reliability issues with the flanges since they're thinner than the Thorleys?

Patriot: I have never heard of this brand and know nothing about them so if you have them...what do you think?

I am replacing mine because the entire exhaust system that's on there now is a hodge-podge leaky mix of really old high beat up stock stuff and poorly done modifications. My pocketbook wants me to lean toward some un-coated Headmans and some header wrap but if it's worth it to spend 3x more on the Thorley & Y-Pipe setup then that's okay too.

[Full Size Jeeper]

I have a set of the Headman Headers, I have not started the rebuilt engine yet, but here is a little info on how they fit. I have aftermarket heads and head bolts and the header flange hits on the head bolts. Had to grind the flange down a little so they would fit. Also you will have to cut a slot in the flange for the dipstick tube or modify the tube.(I and others have a thread in the tech forums for cutting the tube) As for the fit, they don't touch the frame or starter, but some on here said bending the trans cooler lines is needed sometimes. Wrapping the headers voids the warranty. Hope some of this helps. Had the headers on and off lots of times to get them fitted correctly. Sending mine off to the exhaust shop next week to have my 3 inch exhaust installed. Will let you know how it goes when I get it back.

[Ristow]

the edelbrock headers are the same as the patriot and are a waste of money. they make no power,theres dyno sheets posted here to prove it.


thorleys are way overpriced,but are nicely made.


ive rane hookers and hedmans. hedmans are decent for the money. hookers are made better but have a square port. however,if you look at everyone elses dogleg port on their headers,you see how undersized and poor;y matched they are. the hookers will actually flow better.

[FlashGordon]

I run Doug Thorleys from BJs in my stock 1985 GW.
With complete 3'' pipe
Fits excellent

https://photos.app.goo.gl/zrUSBmvcwfP5GZEu6

https://photos.app.goo.gl/maD5LADh9k72T4qa7

https://photos.app.goo.gl/maD5LADh9k72T4qa7

[Tbeach]

Doug Thorley headers from BJ's installed last year on a '91 GW. Approx. 4 inch lift between springs and reverse shackle.

[TheWeekendWagon]

Thanks everyone! This is good info and I appreciate the photo Tbeach! That doesn't look like it hangs down any lower than the crossmember from that angle.

[Crankyolman]

I have Headmans, the right one is real close to contacting the starter and if I use anything but Headman gaskets they leak. That said with the Headman gaskets I've had no issues with them.

[rang-a-stang]

I have Hedmans and they eat stock gaskets but are otherwise fine. They fit very well on my rig. I used Remflex gaskets this time and they seem to be holding up but I only have about 30 minutes of run time on them (the gaskets) since my rebuild.

Like Ristow said, our exhaust ports are horrendous. If you look in my build thread you can see how bad mine were. also, heed Full Size Jeepers advice about the dipstick tube. I cut my header flange to accomodate (again, you can see it in my build thread) but I think what Full Size Jeeper did is a MUCH better solution.

On a mostly stock build, I doubt you will feel much power difference between any of the full length headers. You WILL feel/hear a significant difference installing headers but if you bought all 4 sets of headers, installed them and compared them, your butt dyno would probably not tell the difference.

Don't forget to account for painting your headers if you do not pay for a coating.

[TheWeekendWagon]

I have Hedmans and they eat stock gaskets but are otherwise fine. They fit very well on my rig. I used Remflex gaskets this time and they seem to be holding up but I only have about 30 minutes of run time on them (the gaskets) since my rebuild.

Like Ristow said, our exhaust ports are horrendous. If you look in my build thread you can see how bad mine were. also, heed Full Size Jeepers advice about the dipstick tube. I cut my header flange to accomodate (again, you can see it in my build thread) but I think what Full Size Jeeper did is a MUCH better solution.

On a mostly stock build, I doubt you will feel much power difference between any of the full length headers. You WILL feel/hear a significant difference installing headers but if you bought all 4 sets of headers, installed them and compared them, your butt dyno would probably not tell the difference.

Don't forget to account for painting your headers if you do not pay for a coating.

Power isn't really much of a concern for me. The GW is never going to be fast haha. That's what sports cars are for. Main reason I am going with headers is because of some shoddy AIR/Heat Riser delete work on my factory manifolds from a previous owner causing them to leak. And factory manifolds are just as pricey as headers so why not.

Sounds like I may just go with the Thorley's and the BJ's bolt-up exhaust system. More expensive yes, but seems to be far less of a headache and I can do it all in my garage without any fabrication. I don't mind paying extra for that.

[Probesport]

I'm running the Patriots, super easy, fast install. I have a 3" BJ's exhaust as well. I am still running the factory Y-pipe which had to be slightly modified, but I will probably just make a new one at some point.

Here is a link to to my header install http://www.ifsja.org/forums/vb/showthread.php?t=183092

The Doug Thorleys are a great option especially with their y-pipe, but it wasn't in the budget at the time when I did it.