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I bought an 88 vert with a crate motor that was poorly installed. They couldn't get it running right. I have pulled the engine and tranny. I have noticed a double gasket on the intake. Intake is an eldebrock and the heads are supposed to be vortec mounted on a 355 roller crate engine. Any idea why the double intake gasket?
I have noticed a double gasket on the intake. Any idea why the double intake gasket?
Yes!
Originally Posted by GotMe1
the heads are supposed to be vortec
I'm guessing that base is a non-Vortec base. Since the Vortec intake ports are slightly higher than the non-vortec ports, you need to stack gaskets to raise the intake a bit, and get a seal. I've done it before when putting a CFI intake on a Vortec long block. Seems like hackery, but it worked just fine, in my case.
I'll be tearing the engine down to spec it and make sure everything is good, mismatched parts seems a possibility. Some of the intake bolts weren't all the way in either.
If the heads, block, or manifold were milled excessively in the past this will cause intake to sit too low and you need thicker gaskets. Usually the gasket thickness is .060 but they make .120 thick gaskets to help wit this problem.
If the heads, block, or manifold were milled excessively in the past this will cause intake to sit too low and you need thicker gaskets. Usually the gasket thickness is .060 but they make .120 thick gaskets to help wit this problem.
That is backwards. If you mill the heads, the intake sits to high on the heads. More gaskets isn't going to help that. In fact, the proper solution for that would be to mill the intake, as well.
From: Las Vegas - Just stop perpetuating myths please.
Originally Posted by Tom400CFI
That is backwards. If you mill the heads, the intake sits to high on the heads. More gaskets isn't going to help that. In fact, the proper solution for that would be to mill the intake, as well.
I was expecting to read the intake had been milled excessively but now i see the higher Vortec ports are the reason. Always learning something new w/sbc combinations - endless combinations.
That is backwards. If you mill the heads, the intake sits to high on the heads. More gaskets isn't going to help that. In fact, the proper solution for that would be to mill the intake, as well.
You are correct, I should not have said heads or block, only the intake should have been in my comment. (Oops, typed answer without much thought)
Last edited by bjankuski; Nov 1, 2015 at 02:26 AM.
I was expecting to read the intake had been milled excessively but now i see the higher Vortec ports are the reason. .
I am not sure why the higher vortec ports are the problem, that is a vortec intake manifold (You can tell by the flat machined bolt mounting pads on the end and the straight up bolts) and it was designed for the vortec heads. I would be leaning towards either the intake mounting surfaces on the intake have been milled too much or the end rails above the china wall on the intake have not been milled at all.(And you have a milled block or heads) If the end rails have not been milled the intake will bottom out on the china wall (I cannot tell from the picture) and be held up away from the head, requiring a thicker gasket. If this happens the ports and bolt holes for the intake will not line up very well.
Last edited by bjankuski; Nov 1, 2015 at 03:23 AM.
Very interesting. This motor had the intake rocker backed completely off on one cylinder which was loaded with oil, actually dripping from header collector. It ran so badly, just like massive vacuum leak. Also, super rich as all the plugs were black .
I am not sure why the higher vortec ports are the problem, that is a vortec intake manifold (You can tell by the flat machined bolt mounting pads on the end and the straight up bolts) and it was designed for the vortec heads. I would be leaning towards either the intake mounting surfaces on the intake have been milled too much or the end rails above the china wall on the intake have not been milled at all.(And you have a milled block or heads) If the end rails have not been milled the intake will bottom out on the china wall (I cannot tell from the picture) and be held up away from the head, requiring a thicker gasket. If this happens the ports and bolt holes for the intake will not line up very well.
I still have to take it apart, but seller claimed that it was a crate motor. Not sure if that means the heads came with it or not. I'm gonna have a lot of measuring to do...
I am not sure why the higher vortec ports are the problem, that is a vortec intake manifold (You can tell by the flat machined bolt mounting pads on the end and the straight up bolts) and it was designed for the vortec heads.
From: Las Vegas - Just stop perpetuating myths please.
Ok so it was the intake then as added gaskets should only move the intake ports and bolt holes higher. Well isnt that the same thing as adding gaskets for aligning the intake ports? Well i guess not if your expecting to align just for an un-milled intake base. And an un-milled base should fit up to a un-milled block & heads. Well maybe for a vortec design base but not a standard GEN 0 base. In that case u need the gaskets to move the base ports (and maybe bolt holes) higher.
Something i think i can see from the pix is the heads - which look like vortecs - have a thick gasket rather than the usual thin (0.24"?) steel shim head gasket. Now this starts to make sense - at least to me. That motor could have vortec heads using a thicker composite gasket (over 0.040") raising the heads - which already have "raised" vortec ports. Now installing a GEN 0 TPI base with lower port locations means u need someway to raise the lower base ports. Ta Da extra intake gaskets! Well i bet the bolt holes on that intake are ground out and elongated too.
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Double Intake Gasket
I was expecting to read the intake had been milled excessively but now i see the higher Vortec ports are the reason. Always learning something new w/sbc combinations - endless combinations.
