Intake perfect fit without gaskets.

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I sent a note to Permatex. I’ll report what they say. Night all.
 
Spadman said:
I sent a note to Permatex. I’ll report what they say. Night all.
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Zero chance silicone sealer by itself will work. That's a disaster waiting to happen. Get the intake milled, it's a simple process for any half way decent machine shop
 
Spadman said:
Now there’s one great reason not to do it. Doesn’t Permatex advertise one impermeable to gasoline?
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Like I said, I’ve never seen or used one.
Newbomb Turk said:
I’ve said this so many times I want to puke.

Machine the intake face. If you machine the intake face of the head because you think the next intake will fit it you’d be wrong.

The guys telling you that bullshit are not engine builders.

You can buy 4 intake manifolds and measure ALL OF THEM and it’s more likely than not that aren’t all the same.

There are production tolerances.

Machine the intake manifold face the thickness of the gasket on each side and send it.

If your shop can machine a cylinder head they can do the intake.

If they tell you they can’t do it go find another shop.
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Couldn’t agree more. There’s also another reason to do the intake and not the heads, we decided if we hacked the intake up it was cheaper to get a new one than mess up a set of heads. That ALONE was enough reason to cut the intake.
 
I’ll say this, we read on here that we should cut the intake the thickness of the gasket and measured our gaskets at .060. We decided to cut .035 off each side and try it and I’m glad we did. The .035 cut was perfect. We figure the gasket crushed about .015.
 
I'd cut the intake. I'm so cheap I would probably make my own gaskets out of heavy-duty tin foil 1st. lol
 
Spadman said:
I don’t remember how much was taken off the intake side of my stock iron heads because it was years ago, but I milled the chamber side at least .060. I had test fit the intake before and thought it was going to be okay, but last night, getting ready to install it for good, it lines up the bolt holes perfect sitting on the china walls and fits flush to the intake face of the heads; without gaskets. I know I have read on here in past threads to cut the face of the manifold in this case the thickness of a gasket plus a cleanup cut. (Sorry I don’t remember which of you gents to credit with this but I did get some good info on fitting intakes from reading a couple of threads.) Problem is, my local machine shop can’t machine intakes and I am way past stripping the block back down to trim the china wall; especially just to have a void to fill with rtv. I really don’t want to strip the heads back down either so: what’s wrong with using rtv to fill the imperfections and bolt it on without a gasket? I will check some more to see if the runners line up but all the bolts start easily by hand. If I do this that leaves open using this air gap in the future with aftermarket heads.
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Take it to a real machine shop , they can do about anything / milling machine .
 
Agree with getting a machine shop to do it properly. I had the heads done "back in the day" when the iron heads were decked on my 440.

I'm just curious...anybody ever use Seal-All? Literally 45 years ago, I had a car with a coil spring decide to hop out of its perch and poke a hole in the gas tank. Wiped it off, lathered some Seal-All on it, and it never leaked again for the 5 more years we had the car. Just curious as it's mentioned nothing really stands up to gasoline.
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Demonx2 said:
Agree with getting a machine shop to do it properly. I had the heads done "back in the day" when the iron heads were decked on my 440.

I'm just curious...anybody ever use Seal-All? Literally 45 years ago, I had a car with a coil spring decide to hop out of its perch and poke a hole in the gas tank. Wiped it off, lathered some Seal-All on it, and it never leaked again for the 5 more years we had the car. Just curious as it's mentioned nothing really stands up to gasoline.
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I don’t remember what I used but I was able to buy a product years ago that stopped a leak in my gas tank; so it is certainly possible. More recently, I used JB Weld on my 1998 Freightliner diesel fuel tank where it rusted through under a decal. It’s held now for 8 to 9 years.
 
Spadman said:
I sent a note to Permatex. I’ll report what they say. Night all.
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The Permatex rep said use Permatex Optimum Gray.

However, you guys have convinced me to cut the intake. I called Hensley’s near Dandridge TN. They are about 3 hours away, but I need to go close there next week anyway. They said I could call in advance and they could do it when I bring it in.

I really think it would be fine but I’m not into even the perception of cutting corners on this build.

Thanks for all your advice. Hope to see you on the road one of these days.
 
Spadman said:
You’re right, I can find a shop, either in TN or in Ohio, and I’ll be in both this month. But; my question is what’s wrong with using something like Permatex Permashield? They recommend it for intake manifolds. I know that one problem with rtv is getting a part back off; but other than that? Permatex advertises parts put on with Permashield to be easily removed and replaced.
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That's all I ever use. I haven't use China wall gaskets on my sbm or SBC in going on 10 years. I have never once had one fail. Street car or derby engine at 300 degrees and everything is self destructing
 
replicaracer43 said:
Zero chance silicone sealer by itself will work. That's a disaster waiting to happen. Get the intake milled, it's a simple process for any half way decent machine shop
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I can 110% tell you for a fact and several thousands of miles. Several years. Unbelievable amount of heat cycles that strictly grey permatex works on its own with zero front or rear gaskets. Been 10 years since I've used one and 20+ engines.
 
Owen 340+6 said:
I can 110% tell you for a fact and several thousands of miles. Several years. Unbelievable amount of heat cycles that strictly grey permatex works on its own with zero front or rear gaskets. Been 10 years since I've used one and 20+ engines.
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Glad it worked for you, but no engine would EVER leave my shop with the intake sealed with permatex sealer. Now on the china walls, yes. But the OP is talking about doing away with intake gaskets between head and manifolds. That's a NO from me
 
replicaracer43 said:
Glad it worked for you, but no engine would EVER leave my shop with the intake sealed with permatex sealer.
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I learned it from hot rod tv and MAS performance engines, if it can hold up to 1800hp big block chebys it's good enough for everything I build people. No problem everyone skins a cat differently, I just was just setting it straight that it does work and it does last and it is another option for people.
 
replicaracer43 said:
Glad it worked for you, but no engine would EVER leave my shop with the intake sealed with permatex sealer. Now on the china walls, yes. But the OP is talking about doing away with intake gaskets between head and manifolds. That's a NO from me
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I think several guys are confused about what needs done. China wall silicon works great. To replace intake gaskets good luck with that.
 
pittsburghracer said:
I think several guys are confused about what needs done. China wall silicon works great. To replace intake gaskets good luck with that.
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I was wondering if that was what some here were thinking. Silicone instead of cork gaskets on the China Walls not "just" silicone instead of intake gaskets.
 
toolmanmike said:
I was wondering if that was what some here were thinking. Silicone instead of cork gaskets on the China Walls not "just" silicone instead of intake gaskets.
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I first read it as using silicone on the manifold faces. That how I read it because it fit without gaskets.

Confusing for sure.
 
TT5.9mag said:
We just cut one a few days ago for @jedrattle Fixturing was a pain in the *** but no one (machine shops) would touch it. This was an rpm air gap on speedmaster heads. We used a .060 edlebrock gasket and had to cut the intake flanges .035. After that it fit great.
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I had to do the same exact on my 360. Speedmaster heads, and RPM air gap. Took off .030 thou and used the Edelbrock gasket. Bolted right up after that.
I don’t know how much was milled off the deck, but the H116cp pistons now stick out .003 above the deck.

Someone on here (or somewhere else) told me the Edelbrock is casted a little thick and most all needed to be cut. I don’t know how much merit that has…
 
mopardude318 said:
I had to do the same exact on my 360. Speedmaster heads, and RPM air gap. Took off .030 thou and used the Edelbrock gasket. Bolted right up after that.
I don’t know how much was milled off the deck, but the H116cp pistons now stick out .003 above the deck.

Someone on here (or somewhere else) told me the Edelbrock is casted a little thick and most all needed to be cut. I don’t know how much merit that has…
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I’ve heard the same thing. I think @replicaracer said it. I think his new screen name is @NC Engine Builder
 
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