Swap a L head exhaust manifold with a F head one

Lyle · Post by **Lyle** » Mon Jul 09, 2018 1:31 pm

Can F-134 exhaust manifold fit on L-134? I understand I’ll have to cut the two mounting holes in half.

Post by **wesk** » Mon Jul 09, 2018 6:26 pm

And how would you fasten the intake manifold to the F-134 exhaust manifold?????

Note that L134 exhaust has a square section that bolts to the intake manifold.

L134 Exhaust

F134 exh

Lyle · Post by **Lyle** » Mon Jul 09, 2018 7:55 pm

This is the main reason (the pre-heat chamber) I'm looking to ditch the L-134 exhaust manifold..... and put on the freer flowing exhaust manifold from a F-134 and forego the Pre-Heat chamber.

Cheers, Lyle

Post by **wesk** » Mon Jul 09, 2018 8:41 pm

I cannot think of any worthwhile reason to do that. That heat chamber is there to improve driveability during cold weather warm-ups. If maintained properly it creates NO headaches.

Back in the day (1950's) when desperate folks actually raced the Willys 4 bangers across the desert trails they just put a set of steel headers on and ran the stock intake or a modified intake that could handle a 2 Brl carb.

Whatever you decide to do make sure you remember to ensure both the intake and whatever you use for an exhaust are mached to make their engine mating port flanges the same thickness.

RonD2 · Post by **RonD2** » Mon Jul 09, 2018 8:57 pm

Maybe it's just me? Take your shots. This is still America and you can do what you want with your stuff.

I'm a rookie and I've read a ton of posts in this forum and others dedicated to preserving this old American iron. But this one has to be near the top......so somebody ought to say it. Do I smell some Bubba-licious here?

Dang it, did I say that out loud?

Bubba gets talked about a lot. Maybe it's time for a Bubba Forum?

Just a thought: if somebody (who lives in Yuma Arizona for example --- been there done that) wanted to ditch the heat riser valve on the L134 manifold why not just take it out? Or better yet cut it out with a big torch?

Dang it! Did I say that out loud again?

mdainsd · Post by **mdainsd** » Mon Jul 09, 2018 9:29 pm

Or just weld it in the summer position.

RonD2 · Post by **RonD2** » Mon Jul 09, 2018 9:55 pm

And Yuma is a great place to live and work! Even in January wearing a sweatshirt and dodging snow-birds. The rest of the time it's pretty H-O-T.

Post by **wesk** » Mon Jul 09, 2018 10:01 pm

Just a thought: if somebody (who lives in Yuma Arizona for example --- been there done that) wanted to ditch the heat riser valve on the L134 manifold why not just take it out? Or better yet cut it out with a big torch? Rolling Eyes

Now this could be described as a DUMB QUESTION! And after you cut it out of the exhaust manifold with a cutting torch just what do you do with that remaining tremendous exhaust leak? Not a lot of cast iron manifolds that do well trying to weld that large of a hole shut.

If one did not want to deal with the just riser then just wire the lever in the closed position.

However since our original poster only said he wanted a more streamlined and efficient exhaust manifold the heat riser was not an issue.

RonD2 · Post by **RonD2** » Tue Jul 10, 2018 7:32 am

Sure thing Wes. Dumb questions are my middle name.

The over-the-top suggestion was meant to convey: just take the flapper off the hinge pin --- not cut a hole in the manifold.

Everything looks cool from the outside.

Has to be more "streamlined" (whatever that means).

Probably not enough Bubba in that recipe. I don't want my grape getting in the habit of thinking that way....no telling where it would lead.

My thinking on this is pretty much limited. If it were really a good idea to merge a F-head manifold to an L-head manifold for "streamlining" then somebody would already have done it --- maybe by hiring an engineer with a flow analysis or an entirely new design (big bucks), then get a patent for it and retire as a gazillionaire.

Post by **wesk** » Tue Jul 10, 2018 9:00 am

Ron, All that riddle talking has you confused.

Above I said; "

However since our original poster only said he wanted a more streamlined and efficient exhaust manifold the heat riser was not an issue.

"

He wanted a smooth flow of exhaust gases.

Above that I already posted the ancient 1950's solution to that need; "

Back in the day (1950's) when desperate folks actually raced the Willys 4 bangers across the desert trails they just put a set of steel headers on and ran the stock intake or a modified intake that could handle a 2 Brl carb.

"

Only a fool would hire an engineer to cutomize the F134 cast exhaust when an excellent selection of aftermarket headers already existed. We even had ported and polished heads back then.

RonD2 · Post by **RonD2** » Tue Jul 10, 2018 10:58 am

That's me Wes, full of dumb questions and easily confused. Sometimes I wonder how I ever survived this far. It's a good thing I have half-heimers and can't remember stuff like that half the time or I might be more concerned about it.

You take me way too seriously. It's hard to convey humor in a forum conversation with somebody you've never met. My poor attempt at suggesting what I thought was obviously an over-the-top solution (like hiring an engineer) was meant only in jest with more than a little humor........mainly directed at how fast odd topics like this usually spiral out of control. The humor is the best thing about it.

Please forgive me having the impression that this forum was mostly focused on M-series truck love and maintenance, with a little humor once in a while. The original post seemed so far from that that it got me laughing out loud was all I meant to say. Next time I'll keep my mouth shut.

I had no intention to offend you, the original poster, or anybody else with my comments. My apology if taken otherwise.

RonD2 · Post by **RonD2** » Tue Jul 10, 2018 2:41 pm

Note to self:

Post by **wesk** » Tue Jul 10, 2018 6:40 pm

No offense was taken. I was just protecting the group from the heavy duty BS so they wouldn't take it as a serious solution.

Whenever I feel the urge to jest I usually try to make use of the emoticons to make sure I am not taken seriously.

radtech · Post by **radtech** » Thu Jul 12, 2018 7:25 am

There are plenty of 4 wheeler web sites out there that will tell you how to Bubba your original military or CJ jeeps.

Lyle · Post by **Lyle** » Fri Dec 21, 2018 3:06 pm

Gents:

I modified the Intake Manifold to align up with the F-134 Exhaust Manifold as well as modified the F-134 Exhaust Manifold.

Cold weather: Not a Problem as the heat from the Exhaust Manifold rises and collects around the Intake Manifold. So NO change in the engines ability to pre-heat the air/fuel charge.

Hot weather: Maybe I'll have to deal with coolant going over 200*F, but as I had the original Radiator completely overhauled new 3 core brass & copper as the original. I don't think so....

I'll report back after I drive it this summer (2019).