88mm Cosworth head gasket
07-15-2010, 11:07 AM
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88mm Cosworth head gasket
Well the last thread I had on this subject disappeared, so I thought I'd start a new one to possibly get some more feedback.
As I previously stated: I am thinking of putting in a 1.1mm Cosworth head gasket, but the smallest bore size they make is a 88mm. Do you think running this gasket would be a problem on my stock bore (87mm) block?
http://www.cosworthusa.com/store/pc/viewPr...2&idproduct=569
My only other option is a stock head gasket, but if I can safely run the 1.1 Cosworth I would really like to as it would lower my compression from stock. I guess I could try a 2mm Cometic also.
(I currently have a 2MM SCE copper head gasket, but it is leaking pressure into the cooling system under boost)
A built block is in the works, this is just something to get me by until I can get it completed.
As I previously stated: I am thinking of putting in a 1.1mm Cosworth head gasket, but the smallest bore size they make is a 88mm. Do you think running this gasket would be a problem on my stock bore (87mm) block?
http://www.cosworthusa.com/store/pc/viewPr...2&idproduct=569
My only other option is a stock head gasket, but if I can safely run the 1.1 Cosworth I would really like to as it would lower my compression from stock. I guess I could try a 2mm Cometic also.
(I currently have a 2MM SCE copper head gasket, but it is leaking pressure into the cooling system under boost)
A built block is in the works, this is just something to get me by until I can get it completed.
07-15-2010, 12:07 PM
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Let me help you.
The most important thing is to make sure the head gasket bore is larger or equal than the engine bore. If you have a gasket that is smaller than the engine bore the gasket will fail. You will have slightly higher compression (~.1) with the smaller bore size gasket. You don't want any gasket overhanging into the bore to act as a hot spot & to attract detonation. It will create a shelf cavity between the bore and the head. Small spaces like that area can be a "dead zone" that will not light on ignition and will contribute to dirty emissions on a motor that has to conform to State requirements.
Comprende?
....and I'm not trolling. I know my stuff
The most important thing is to make sure the head gasket bore is larger or equal than the engine bore. If you have a gasket that is smaller than the engine bore the gasket will fail. You will have slightly higher compression (~.1) with the smaller bore size gasket. You don't want any gasket overhanging into the bore to act as a hot spot & to attract detonation. It will create a shelf cavity between the bore and the head. Small spaces like that area can be a "dead zone" that will not light on ignition and will contribute to dirty emissions on a motor that has to conform to State requirements.
Comprende?
....and I'm not trolling. I know my stuff
07-15-2010, 12:10 PM
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[QUOTE=TRBOKEV,Jul 15 2010, 11:07 AM]Well the last thread I had on this subject disappeared, so I thought I'd start a new one to possibly get some more feedback.
As I previously stated: I am thinking of putting in a 1.1mm Cosworth head gasket, but the smallest bore size they make is a 88mm.
As I previously stated: I am thinking of putting in a 1.1mm Cosworth head gasket, but the smallest bore size they make is a 88mm.
07-15-2010, 01:18 PM
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Originally Posted by lotus7racer,Jul 15 2010, 12:07 PM
Let me help you.
The most important thing is to make sure the head gasket bore is larger or equal than the engine bore. If you have a gasket that is smaller than the engine bore the gasket will fail. You will have slightly higher compression (~.1) with the smaller bore size gasket. You don't want any gasket overhanging into the bore to act as a hot spot & to attract detonation. It will create a shelf cavity between the bore and the head. Small spaces like that area can be a "dead zone" that will not light on ignition and will contribute to dirty emissions on a motor that has to conform to State requirements.
Comprende?
....and I'm not trolling. I know my stuff
The most important thing is to make sure the head gasket bore is larger or equal than the engine bore. If you have a gasket that is smaller than the engine bore the gasket will fail. You will have slightly higher compression (~.1) with the smaller bore size gasket. You don't want any gasket overhanging into the bore to act as a hot spot & to attract detonation. It will create a shelf cavity between the bore and the head. Small spaces like that area can be a "dead zone" that will not light on ignition and will contribute to dirty emissions on a motor that has to conform to State requirements.
Comprende?
....and I'm not trolling. I know my stuff
Comprende?
07-15-2010, 01:25 PM
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Originally Posted by siadam,Jul 15 2010, 12:10 PM
So did mine.
Nice modding
Instead of "cleaning" out the un-needed posts, the entire post is deleted.
I'm glad we are punished b/c of someone else's trolling.
Like I said in your other thread before it was carelessly deleted, I'd stick w/the stock hg. We know it works.
Why take a gamble with something thats not proven.
Nice modding
Instead of "cleaning" out the un-needed posts, the entire post is deleted.
I'm glad we are punished b/c of someone else's trolling.
Like I said in your other thread before it was carelessly deleted, I'd stick w/the stock hg. We know it works.
Why take a gamble with something thats not proven.
The only reason I was thinking of putting a thicker gasket again is because this is only temporary till I get my built block together..
Yeah I think I'll just put the stock gasket and new stock bolts in for now and pull some timing out of my tune along with lowering boost.
If only the cometic 2mm would work.. Then I wouldn't have to change squat till my new motor and new tune. I know a few people running the cometic here in socal.. Hmmm.
07-15-2010, 02:06 PM
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I'm running the cometic gasket (unmodified) up here in NorCal. Right now it's set at 14 psi @ 450whp. I think the gaskets that might have failed might have been partly due to the gasket moving during the re-installion of the head. Sometimes the gasket will move and cause hot spots, ect.
Good luck! If I were to do it all over again, I'd go with the OEM gasket. More power @ lower boost and a gasket you know won't fail.
Good luck! If I were to do it all over again, I'd go with the OEM gasket. More power @ lower boost and a gasket you know won't fail.
07-15-2010, 02:13 PM
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Originally Posted by A51_AP1,Jul 15 2010, 02:06 PM
I'm running the cometic gasket (unmodified) up here in NorCal. Right now it's set at 14 psi @ 450whp. I think the gaskets that might have failed might have been partly due to the gasket moving during the re-installion of the head. Sometimes the gasket will move and cause hot spots, ect.
Good luck! If I were to do it all over again, I'd go with the OEM gasket. More power @ lower boost and a gasket you know won't fail.
Good luck! If I were to do it all over again, I'd go with the OEM gasket. More power @ lower boost and a gasket you know won't fail.
How exactly does the gasket move? There are two dowels that hold it in place.
Arte you using OEM bolts or ARP's?
Thanks for the input on the Cometic, I appreciate it.
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07-15-2010, 03:15 PM
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Originally Posted by 03supers2k,Jul 15 2010, 02:22 PM
Kevin im using the 2mm Cometic also with ARP studs. i just passed 5000 miles no problems yet 
I got to get a ride in your car soon Lee!
