Intake perfect fit without gaskets.

[Spadman]

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.

 

[PRH]

Find a shop that can cut the intake.

Most overhead style resurfacers that have a rollover fixture can do it, or a guy with a decent sized knee mill and enough tooling, and who knows how to use it.

 

[Spadman]

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.

 

[Spadman]

Correction, upon closer examination it seems Permatex only recommends Permshield as a gasket dressing for an intake manifold.

 

[413]

put it on with sealer only and report back, tell us how it works out.

 

[TT5.9mag]

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.

 

[toolmanmike]

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.

Mine fit perfect with out gaskets so I used the steel shim gaskets in my gasket set. Sprayed them with a little permatex and silicone on the China walls. No leaks after 10 years. Cast heads and intake though.

 

[Spadman]

Mine fit perfect with out gaskets so I used the steel shim gaskets in my gasket set. Sprayed them with a little permatex and silicone on the China walls. No leaks after 10 years. Cast heads and intake though.

I’m glad yours worked out. Certainly an option but I would have to enlarge my steel gaskets’ port openings. The ones I have are smaller ports than the gasket I port matched to. I’ve thought about cutting a paper gasket out to match and dressing each side with a thin coat of black permatex, but the question remains; what does the paper gasket add?

 

[RustyRatRod]

Just for the heck of it, have you tried it with the gaskets? Sometimes it will line up anyway. Probably won't, but it's worth a try.

 

[Spadman]

put it on with sealer only and report back, tell us how it works out.

I will be glad to report back if I do it. I just wasn’t wanting to be the first. I’m going to check the fit more to make sure I don’t have any major angle mismatch.

 

[TT5.9mag]

I will be glad to report back if I do it. I just wasn’t wanting to be the first. I’m going to check the fit more to make sure I don’t have any major angle mismatch.

There’s not a sealer that I know of that gasoline won’t turn to Goo after a while. I wouldn’t do that.

 

[Spadman]

Just for the heck of it, have you tried it with the gaskets? Sometimes it will line up anyway. Probably won't, but it's worth a try.

Yes, it sits too high even with the steel gaskets, though most of the bolts will start. Without a gasket all the bolts easily thread by hand.

 

[toolmanmike]

Yes, it sits too high even with the steel gaskets, though most of the bolts will start. Without a gasket all the bolts easily thread by hand.

You need it machined some then. (or the intake surface of the heads shaved)

 

[Scampin]

Just went through this myself. No local shop was interested. We did it on a vertical mill. Took forever to setup but came out good.

 

[RustyRatRod]

Yes, it sits too high even with the steel gaskets, though most of the bolts will start. Without a gasket all the bolts easily thread by hand.

Well there's your answer.

 

[65Val]

...or have the intake surface of the heads cut...that way any non-cut intake will fit those heads.

 

[toolmanmike]

Just went through this myself. No local shop was interested. We did it on a vertical mill. Took forever to setup but came out good.

Mine was done on a Bridgeport over a lunch hour.

 

[Spadman]

...or have the intake surface of the heads cut...that way any non-cut intake will fit those heads.

Yes, that is a good option of course. I’m just wondering if there’s someone out there who did it and it failed. Mechanic friends tell me OEM’s have used Silicone only but I have always used a gasket even if cut out myself. That said I pretty much always use some kind of dressing, including g a thin spread of black rtv.

 

[Spadman]

There’s not a sealer that I know of that gasoline won’t turn to Goo after a while. I wouldn’t do that.

Now there’s one great reason not to do it. Doesn’t Permatex advertise one impermeable to gasoline?

 

[Spadman]

I went back to my shop just now and threaded in four bolts semi tight, with no gasket. All the bolts go in easily. I looked inside with a cheap Harbor Freight bore camera and saw no problems with alignment. The head has been gasket matched, but not the intake as yet so all I could tell is that there is no ledge going into the head. The angles of the faces of the head and intake are spot on. There were only two places around the perimeter where there is any gap at all. Couldn’t find my feeler gauges at the moment so I stuck a putty knife in, 0.023 inches thick. Pics attached. The intake fits perfectly at the back. The two gaps are one side of the front china wall and the opposite side top of intake. I think if I do machine it the geometry is okay so simple cuts only.

 

[Newbomb Turk]

Yes, that is a good option of course. I’m just wondering if there’s someone out there who did it and it failed. Mechanic friends tell me OEM’s have used Silicone only but I have always used a gasket even if cut out myself. That said I pretty much always use some kind of dressing, including g a thin spread of black rtv.

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.

 

[65Val]

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.

Well, whatever….just did this on a 360 I just finished. I have 4 intake manifolds to chose from, and all fit perfectly.

 

[Newbomb Turk]

Well, whatever….just did this on a 360 I just finished. I have 4 intake manifolds to chose from, and all fit perfectly.

Yeah, you got lucky.

No two blocks have the exact same deck height. Unless someone machined them the same.

Same thing for the heads.

Same thing for the manifolds.

The upshot is on ALL of these parts is when they are machined they do NOT machine to a number.

They have a maximum deck height and a minimum deck height. The nominal height could be 9.560 or whatever is called out.

I can tell you for a fact I’ve had blocks that were fall taller than nominal.

When they machine this junk they machine them until they get a clean surface. They don’t machine on it any more, even if it’s over nominal.

Same thing with the cylinder heads and intake manifolds.

So claiming that you can drop any intake on an engine because the face of the head was machined is just wrong. That’s why I call it bullshit because I’ve been around long enough to know it is bullshit.

Here is a perfect example.

My block measured 9.6xx. I forget the exact number but it was over nominal.

Then it was machined until the deck of the piston is .048 out of the bore. I can’t remember but I think it took .090 to get it there.

Plus the heads were milled .050. You think a single intake manifold off the shelf will fit without work? It shouldn’t, but my tunnel ram fit perfectly. And it’s brand new.

Now, when I had the single 4 on this junker I had to machine .065 off the face of the intake to get it to fit on this exact same engine. Not a thing changed.

If I had milled the heads I would have fucked myself with the tunnel ram. I’d be stacking gaskets. Which doesn’t bother me but that’s why I don’t mill the piss out of the head.

Gaskets and intake manifolds are far cheaper than cylinder heads.

So saying machining the intake face is the correct way to do it is bullshit.

Guys who actually build this junk get it.

 

[65Val]

Yeah, you got lucky.

No two blocks have the exact same deck height. Unless someone machined them the same.

Same thing for the heads.

Same thing for the manifolds.

The upshot is on ALL of these parts is when they are machined they do NOT machine to a number.

They have a maximum deck height and a minimum deck height. The nominal height could be 9.560 or whatever is called out.

I can tell you for a fact I’ve had blocks that were fall taller than nominal.

When they machine this junk they machine them until they get a clean surface. They don’t machine on it any more, even if it’s over nominal.

Same thing with the cylinder heads and intake manifolds.

So claiming that you can drop any intake on an engine because the face of the head was machined is just wrong. That’s why I call it bullshit because I’ve been around long enough to know it is bullshit.

Here is a perfect example.

My block measured 9.6xx. I forget the exact number but it was over nominal.

Then it was machined until the deck of the piston is .048 out of the bore. I can’t remember but I think it took .090 to get it there.

Plus the heads were milled .050. You think a single intake manifold off the shelf will fit without work? It shouldn’t, but my tunnel ram fit perfectly. And it’s brand new.

Now, when I had the single 4 on this junker I had to machine .065 off the face of the intake to get it to fit on this exact same engine. Not a thing changed.

If I had milled the heads I would have fucked myself with the tunnel ram. I’d be stacking gaskets. Which doesn’t bother me but that’s why I don’t mill the piss out of the head.

Gaskets and intake manifolds are far cheaper than cylinder heads.

So saying machining the intake face is the correct way to do it is bullshit.

Guys who actually build this junk get it.

All well and good, but off the topic of this thread. If you’re saying intakes, heads and blocks are all so far out of spec, you have to mill anyway, I’m just saying, if you have to mill, you can mill the intake or the head intake surface…both get you to the same conclusion. Not argueing any further…has worked for me in the past, and I will continue to do it this way because it works…..your mileage may vary.

 

[toolmanmike]

Yeah, you got lucky.

No two blocks have the exact same deck height. Unless someone machined them the same.

Same thing for the heads.

Same thing for the manifolds.

The upshot is on ALL of these parts is when they are machined they do NOT machine to a number.

They have a maximum deck height and a minimum deck height. The nominal height could be 9.560 or whatever is called out.

I can tell you for a fact I’ve had blocks that were fall taller than nominal.

When they machine this junk they machine them until they get a clean surface. They don’t machine on it any more, even if it’s over nominal.

Same thing with the cylinder heads and intake manifolds.

So claiming that you can drop any intake on an engine because the face of the head was machined is just wrong. That’s why I call it bullshit because I’ve been around long enough to know it is bullshit.

Here is a perfect example.

My block measured 9.6xx. I forget the exact number but it was over nominal.

Then it was machined until the deck of the piston is .048 out of the bore. I can’t remember but I think it took .090 to get it there.

Plus the heads were milled .050. You think a single intake manifold off the shelf will fit without work? It shouldn’t, but my tunnel ram fit perfectly. And it’s brand new.

Now, when I had the single 4 on this junker I had to machine .065 off the face of the intake to get it to fit on this exact same engine. Not a thing changed.

If I had milled the heads I would have fucked myself with the tunnel ram. I’d be stacking gaskets. Which doesn’t bother me but that’s why I don’t mill the piss out of the head.

Gaskets and intake manifolds are far cheaper than cylinder heads.

So saying machining the intake face is the correct way to do it is bullshit.

Guys who actually build this junk get it.

I think mine only got a .010 or .015 slice to make things right. It wasn't much.