Head Gasket Bore???
03-08-2014, 11:49 AM
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Head Gasket Bore??? I'm about to purchase a new set of Head Gaskets for the new setup and I'm having issues finding out how max\min gasket bore is acceptable.
I have a 3.898 Bore on the block (LS1), however my 58cc combustion chamber on my heads (TEA Stage II LS6 2.04 I\ 1.575 E) measures 3.905 at the widest point.
I want a .040" thickness on the gasket, so would the Cometic 3.910 gasket work or should I play it safe and go with a Mr. Gasket 3.945. I haven't been able to find a gasket with a bore in between those two.
Cometic 3.910" .040"
Mr.Gasket 3.945" .040"
Please do not pay attention to the price as I will not be purchasing either gasket through either of these companies. I am focusing and looking for insight on the proper size and the tightest "quench" I can get. Too big of a gasket bore and you begin to lose compression, to tight and you burn the head gasket due to in being present in the combustion chamber. (Note- I'm not aware of how much compression I would actually lose going with a larger gasket, however the search button tells me this will happen. No matter how slight it may be, I am trying to obtain as much compression as possible.)
Let me know your opinions,
James
I have a 3.898 Bore on the block (LS1), however my 58cc combustion chamber on my heads (TEA Stage II LS6 2.04 I\ 1.575 E) measures 3.905 at the widest point.
I want a .040" thickness on the gasket, so would the Cometic 3.910 gasket work or should I play it safe and go with a Mr. Gasket 3.945. I haven't been able to find a gasket with a bore in between those two.
Cometic 3.910" .040"
Mr.Gasket 3.945" .040"
Please do not pay attention to the price as I will not be purchasing either gasket through either of these companies. I am focusing and looking for insight on the proper size and the tightest "quench" I can get. Too big of a gasket bore and you begin to lose compression, to tight and you burn the head gasket due to in being present in the combustion chamber. (Note- I'm not aware of how much compression I would actually lose going with a larger gasket, however the search button tells me this will happen. No matter how slight it may be, I am trying to obtain as much compression as possible.)
Let me know your opinions,
James
Last edited by FEAR LS; 03-08-2014 at 04:07 PM.
03-08-2014, 12:48 PM
#2
I'm not an LS expert, I can't speak with authority about the gasket bore. I would say that the 3.910 would be best, so it doesn't intrude into the chamber. But I could be wrong.
But I can talk about quench. Quench should be right about 0.040". The stock LS1 piston sticks up out of the block a little bit. So you need to use a gasket that will be 0.040" plus deck height. If you're going to be racing at high rpm's, you're better off with slightly more than slightly less, because the rods will stretch a little at those rpm's.
But I can talk about quench. Quench should be right about 0.040". The stock LS1 piston sticks up out of the block a little bit. So you need to use a gasket that will be 0.040" plus deck height. If you're going to be racing at high rpm's, you're better off with slightly more than slightly less, because the rods will stretch a little at those rpm's.
03-08-2014, 04:10 PM
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I'm not an LS expert, I can't speak with authority about the gasket bore. I would say that the 3.910 would be best, so it doesn't intrude into the chamber. But I could be wrong.
But I can talk about quench. Quench should be right about 0.040". The stock LS1 piston sticks up out of the block a little bit. So you need to use a gasket that will be 0.040" plus deck height. If you're going to be racing at high rpm's, you're better off with slightly more than slightly less, because the rods will stretch a little at those rpm's.
But I can talk about quench. Quench should be right about 0.040". The stock LS1 piston sticks up out of the block a little bit. So you need to use a gasket that will be 0.040" plus deck height. If you're going to be racing at high rpm's, you're better off with slightly more than slightly less, because the rods will stretch a little at those rpm's.
Thanks .boB
03-08-2014, 06:20 PM
#6
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I would go at least 0.030" bigger than the head bore.
I'm running a 4.135" head gasket on my 3.903" bore engine, but that is another story. Nothing wrong with going oversize, except for a minor impact on the clearance volume.
I'm running a 4.135" head gasket on my 3.903" bore engine, but that is another story. Nothing wrong with going oversize, except for a minor impact on the clearance volume.
03-08-2014, 07:52 PM
#7
The head gasket should be the same size (or next size larger) than the cylinder bore or chamber (which ever is the largest). As it minimizes the crevice volume and the gasket embossing is located towards the ID of the cylinder liner vs too far towards the OD and the aluminum deck.
I would use the 3.910 .040 Cometic. The squish clearance should be .035-.045, so your good with the .040 gasket.
Russ Kemp
I would use the 3.910 .040 Cometic. The squish clearance should be .035-.045, so your good with the .040 gasket.
Russ Kemp
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03-08-2014, 09:59 PM
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The head gasket should be the same size (or next size larger) than the cylinder bore or chamber (which ever is the largest). As it minimizes the crevice volume and the gasket embossing is located towards the ID of the cylinder liner vs too far towards the OD and the aluminum deck.
I would use the 3.910 .040 Cometic. The squish clearance should be .035-.045, so your good with the .040 gasket.
Russ Kemp
I would use the 3.910 .040 Cometic. The squish clearance should be .035-.045, so your good with the .040 gasket.
Russ Kemp
