Headers or Not??

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Aug 28, 2006
Which headers do you guys like... I've looked at SOR, Man-a-fre, JT outfitters and Marks off road....

Anyone gave advice on the best one?

Also, I noticed that SOR headers have two extra bolt hole locations at cylinder 1 & 6... Buy my cylinder head only has the stock 6 studs to mount it to. Will it work?

Thanks in advance for suggestions!
Also.... I've got three on the tree... Will headers work without modifying he linkage?
One vote for "not". I've got a header and it takes forever to warm up in cold weather. Since I bought the rig with a header, I can't say anything about power, but I'm guessing the power gains are marginal.
The best header I've run (and I've run a few) is the old Downey header..which is the one Mark A. sells.
Mark A. gets my vote.
I'm going through this now.

In my research, it was also recommended to get a fluid heat riser to aid in the warm up issues. I got mine from MAF (should be here today).
Header questions

Thanks for the feedback.

Still need to know about the extra bolt holes on some new headers near cylinder 1 & 6.

If I get a header will I have to drill into the engine block???

Also, Mark at MarksOffRoad says that the 3 speed on the column requires modifications... Has anyone got pictures of this being done?? :hmm:
Disclaimer: I've never (yet) run headers on a 40, but I've installed and run them on lots of other vehicles, including a 3FE-powered FJ80, so these observations are only my experience with headers in general:

1. Without other engine mods (induction upgrades, more aggressive cam, higher compression, etc.) headers by themselves will do little or nothing to improve performance. They usually make things simpler and less complex though; not a bad thing in and of itself.

2. Every set of headers I've ever had eventually rusted out from the inside. Ceramic and other specialty coatings can delay the inevitable, but in the end rust still wins. Ergo, headers are not a permanent fixture, you might have to replace them if you're keeping your truck for a long time. Stock manifolds rust too, but thick cast iron takes longer than the life of the truck to rust through. The thickness of the steel tubing in headers is miniscule compared to the thickness of a cast-iron manifold.

3. Because of the thinner material and the vastly greater surface area of headers, they radiate a LOT of heat into everything nearby - the engine compartment and the firewall (and hence the cab and floorboards) for example. Heat in the engine compartment tends to bake vacuum lines and plastic parts to brittleness. You can mitigate this somewhat by wrapping the headers but this encourages rust from the outside as well as the inside.

I'm not against headers, like I said I've used them a lot on many vehicles. You just need to be aware of the trade-offs for running them to make an informed decision on whether to install them or not.
Street legal headers on my 77. Jim, from Downey Off Road, hand delivered them and offered good personal instructions for installation and after smog use. The headers came with a perforated stainless type gasket and Jim strongly suggested using the K&W Copper Coat Gasket Compound. Glop it on thick. Two CARB stickers came with the purchase.

Available from Mark's Off Road.
fj40 032.jpg
Thanks for the info!


That looks pretty sweet!...

So did Downey advise you on the bolts at cylinder # 1 and #6?

In your photo it looks like you didn't use those bolt holes.

Is that right?

I'm leaning towards Marks Off Road headers at the moment. He says that the 3 speed does need modification but he can instruct on how it is done.
I vote for headers as I always seemed to have trouble getting the stock manifold to downpipe connection sealed up on my first cruiser. I run a Downey header and use a liberal amount of coppercoat on each side of the gasket. No leaks. I also swapped out all bolts for the intake/exhaust for studs and nuts.
I personally would vote no, if you do wrap them with a heat wrap, they get crazy how and put a ton of heat under the hood causing other issues especially with the gas in the carb getting to hot after you park it. Like said they add no real performance increases but are louder. Louder can end up just being more annoying with the top off. We put a header on our cj8, the original manifold was really warped and as soon as we took it off, it was impossible to bolt back on. When I rebuild the cj8 the header will be gone, but it does sound nice, but I would prefer quieter now.
Marks headers. No drilling on my 1/75 2F. May not add much performance, but they look sweet!

Sent from the Bahamas
On the "F" motor it does only have 6 studs to mount the intake/exhaust manifold... Maybe there are 8 studs on the "2F"... I don't know.

Yeah my stock exhaust manifold is definitely warped... Prolly won't go back on.


That does looks good... So did you use sealant with the new gasket or not?
I used what Mark A. recommended. Can't remember what it is called though. It's the copper stuff.

Sent from the Bahamas
Make sure the flange thickness is the same as the intake flanges, they share a couple of the bolts...

Also, in my case, the chrome set I have now has outlasted the last two painted sets combined and then some... all mine were bought from Man A Fre
I'm really leaning towards Marks offroad for the headers.

Even his gasket seems better than the OEM.

Do I need to block off the bottom of the intake??
headers ... radiate a LOT of heat into everything nearby - the engine compartment and the firewall (and hence the cab and floorboards)


my truck had ceramic coated chromed headers when I bought it (although you couldn't see the chrome anymore under all the dirt :hillbilly:) - eventually, like all headers, they cracked

I was too cheap to spring for ceramic coated again at the time - what a mistake :bang: now I am only waiting until they crack, too, so I can gladly spend the money for the noticeable cooler ceramic coated headers, again :rolleyes:
Do I need to block off the bottom of the intake??

No, it's already closed.
I've used the Fel-pro gasket before, I put on my first Remflex gasket last time (about a year ago) I like it too.

Users who are viewing this thread

Top Bottom