Head gaskets
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Joined: Jan 2019
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From: Mesa, AZ
Head gaskets
Hey all. I discovered a small coolant leak in my lifter valley at #5 cylinder. I’ll be pulling my heads and sending them to the machine shop. Hopefully they just need a resurfacing. I’m looking for suggestions on head gaskets. I have a 383 4.000 bore .040 over 10:1 compression. Heads are BluePrint H8002K aluminum.
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i took a couple of pieces of wood and made up the 2 ends from the intake manifold. made a pressure tester from a boat crossover. (chrome pipe setup that replaces water pump in some boats but you can use the water pump too. drill thru end intake bolt holes to thru wood to get holes at the right angle. gasket and silicone the blocks on the water passages on intake faces of heads. now you can pressure test block and heads with no intake in the way. get a little soapy water and start painting to look for bubbles.
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Has your block been decked? If so how much did they remove. Ask the shop if they mill the hesds how much is removed. A stock deck height is 9.025. Take the .025 and subtract that from the desired quench which is about .040 and the result is the compressed gasket or shim thickness for an un-machined deck and head.
If either is machined, add that to the compressed thickness
Summit lists them by generation block, bore size and compression thickness. I like Felpro and they usually sell one each. So check the package quantity. Stock blocks are generation 1.
If either is machined, add that to the compressed thickness
Summit lists them by generation block, bore size and compression thickness. I like Felpro and they usually sell one each. So check the package quantity. Stock blocks are generation 1.
Last edited by Rescue Rogers; May 8, 2019 at 09:15 AM.
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From: Mesa, AZ
I haven’t pulled the heads yet. The block is a BluePrint 383 stroker installed by the PO that he said he got from a storage deal. He said it was new in the crate, so I doubt it’s been decked unless it was done by BluePrint. As for the intake manifold, I pulled off the Perfomer he installed and replaced it with a brand new Perfomer EPS. I pressure tested the cooling system before and after. No change. That eliminates the possibility of a leaking intake. BTW when removing the old intake I noticed he used Fel-Pro 1206 for large port heads instead of 1205, which he should’ve used. Also, the base plate gasket he used looked like it was too small for the Perfomer. I think It wasn’t sealing properly and created a lean condition causing the engine to get hot. He wouldn’t have known because the temp sending unit wasn’t installed because it was too large for the new heads. Why didn’t he just install it in the intake? I don’t know. I think he was operating a little outside his wheelhouse.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Sounds like it.
Looks like you have s good grasp on the situation though. You maybe able to go to the Blue print site to see if they deck the blocks to true them before shipping
Looks like you have s good grasp on the situation though. You maybe able to go to the Blue print site to see if they deck the blocks to true them before shipping
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Joined: Jan 2019
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From: Mesa, AZ
Thanks. Good advice guys. I called BluePrint. All their engines go out with zero deck height. The Fel-Pro gaskets they use have .039 crush thickness. I’m trying to decide between MLS style gaskets or composite like Fel-Pro 1010. The engine was installed in a salvage title vehicle, so it doesn’t have a lot of run time on it. Thoughts?
Last edited by Batty Mantis; May 8, 2019 at 03:57 PM.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,108
Likes: 9,237
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
If I could get my hands on a blueprint engines motor for cheap, I would jump all over it. Since you have it, I would get it running. When they say zero deck its 9.00 so the .039 is perfect for you. Hopefully the heads check out.. I hear good things on the MLS but I think they need a rougher surface, not sure though.
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