We seem to have a recurring exhaust leak at the center of the manfiold.....the bolts loosen up over time and it leaks....plus I still feel like we might have a small intake manifold leak.....havent been playing with it much lately due to life and weather....the warm snap has me thinking agai,

We are using the green composite gasket , and yes I knew it was a gamble. I know several folks say they work great.....in our case, not great.

That said, was looking at Remflex on the summit site and one person wrote that that they had to swap studs because of how thick the remflex gasket was.....any truth to this?

Also, hoping we can just yank the intake/exhaust as a unit and leave the remflex heat box gasket as it is, replace the gasket at the head and bolt everything back on.,.,,, or is it best to redo the heat box again too, tightening that up once the bolts at the head are tight?

How tight are you making them. Before removing and replacing you might as well crank them down some. The green gasket can take quite a bit more than whatever they call for. (10#) I never torque mine

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Who makes/sells this green gasket?

I have a Remflex gasket on mine right now and didn't add any longer studs. I am running Clifford headers and an Offy intake though.

Afraid to crack the exhaust manifold......isnt too much torque an issue because the maifolds need to slide a bit expanding/contracting?

Its a brand new exhaust manifold and $$$$$

Brian Droschak "Brian" on here had some made up at a very reasonable price.

I forget that people are using stock manifolds sometimes, sorry. I would still try tightening it up some before I gave up on it. I guess I would not worry too much if the manifold cracked, I'd just pick one up over in the corner of the shop!

PS. Of all the bolts that I have had come loose, I have never had an intake / exhaust stud nut come loose. Like I say, I would go tighter. Good luck

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Well, when I found I needed an exhaust manifold after the spring broke on ours, I couldn't find a good used one...had to buy a new one.....don't want to ruin 300 bucks worth of cast-iron.

Kid tightened up the bolts to 10 lbs...they were a little loose he said.....car still sounds like a freight train due to the leak.......dammit....always something. Even before the exhaust leak, I was thinking we might have a vac leak at the intake manifold mating surface...still have a rough ish idle in drive......very regular in roughness, like a dead cylinder. ..but we had confirmed we had compression across all 6.......

If we did torque them down more, what is a safe torque spec with the green gasket, without worry of causing issues with the exhaust manifold?

Just ordered the remflex intake/exhaust gasket online.... $33 shipped, not bad.

Does remflex make the exhaust pipe flange gasket as well?

Will have to replace that, I figure, when we do the manifold.

I have used remflex gaskets with stock studs and never had an issue with the length of the stud.

10 ft lbs is not much clamp load, so to make that work:

* be absolutely sure that the faces of the cylinder head and manifolds are flat and clean, when you checked these with a known good straight edge, what did you find? If you are installing the intake and exhaust as an assembly, then the intake and exhaust faces, as an assembly need to be flat.

* without the manifold in place,,will the nuts spin on to the stud threads to the depth needed to put clamp load on the manifold with almost zero finger pressure? You want the tightening force to go into the manifold, not into overcoming thread friction.

* what torque measuring system are you using, at 10 ft lbs, a foot pound torque arm is barely loaded, Get one that measures in inch lbs,,so you are reading up into the scale.

Thanks for the reply!

So, long story -- I had had the shop that rebuilt our engine also grind the original 1 bbl intake/exhaust manifolds flat, together......but of of course, there was project creep and we ended up going to a super 6 setup. SO I wasted $50 on that planing LOL.

When I went to assemble the "new" 2 bbl intake, which was flat by itself, and the brand new aftemarket exhaust manifold (our old one had a broken flapper spring) together, I assembled and then checked the flatness together. It was pretty flat, at least to my eyes...so we bolted it together with the green gasket as it was.

Looking back, either the manifolds were not PERFECT, or the green gasket isnt sealing right or probably a little of both. Hoping I can just yank the assembled inbtake /exhaust as-is off the engine and slide a new gasket into place without splitting the two. The way folks talk about Remflex gaskets, this should be doable I hope.

yeah, the nuts do/did spin on nice and easy by finger.....

We are in fact using a 3/8" drive FT LB torque wrench.... maybe our TW is off and not hitting 10 lbs at that range?

WIll have to see if Harbor Frieght has an INCH pound clicking torque wrench. I have an old beam style inch/lb wrench but not sure how accurate it is after all these years.

unless the beam is bent or the scale is damaged, beam style torque wrenches do not go out of calibration,, its the click wrenches that can drift,

of course with a beam wrench you need to be able to look directly at the beam - scale to read it properly, if viewed from an angle you induce error

a visual check on flatness can also be inaccurate, the machine shop that did the engine work should have a good straight edge or a flat table, check it end to end and corner to corner,

I did have a problem with the stud length when installing a Remflex gasket, Super Six intake, '62 exhaust manifold, and the later, thicker triangle washers. There just wasn't enough thread to get the nuts started. Switching back to the thinner triangle washers solved it for me. Next time, I'll put in slightly longer studs.

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

I have never used a torque wrench once in the dozen or so engines I have changed them on. If I would have to guess I would say I am closer to 20 or 25#. I use a stubby 3/8" ratchet and socket on the ones I can get a socket on. The others I use a 1/2" wrench on and give them a good strong pull.

The green gasket is harder and therefore last longer than anything I have ever used. I have re-used them 3 to 4 times if you lightly grease the faces. The intake and exhaust will pull into the gasket some over time so you may need to re-check them

I just put a Dutra and rear factory half on a truck with the Green gasket and it worked perfectly. Again I would say if you have bolts that are coming loose you are not tight enough.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

I installed Remflex 8 years ago and they're holding up fine. No problems with them if using the thinner washers.

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If it was easy, everybody would be doing it.

This makes logical sense to me..........

Can you torque the middle bolts tighter?

Then when the manifold expands, it will expand away from the center...........

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

I honestly don't know if tightening the manifold tighter is a cause for worry or not. Is it the tighter bolts that would cause a crack or is it the 30 or 40 years of heat cycling that causes an older manifold to crack? Since he has a new one would it be tougher?? Someone smarter than me needs to speak up.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6