Block and head groove?

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dartfreak75

dartfreak75

Restore it, Dont part it!
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I was looking at the spare 360 I bought back in the spring and I noticed something weird. Maybe this is common and iv just never seen it but there is a Grove in the head around the combustion chamber and a matching bump around the cylinder on the block. I know this block has been machined its bored .030 over, is this common is this machined into them for better mating?

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It's called "o-ringing" heads, it helps to seal the head to the block with high compression ratios. It works very well with LA engines that only have 10 head bolts.
 
Yup. Block's been o-ringed. Did it have copper head gaskets?
 
Demonracer said:
It's called "o-ringing" heads, it helps to seal the head to the block with high compression ratios. It works very well with LA engines that only have 10 head bolts.
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Im thinking someone put alot into this build. I think the deck has been milled It looks like the speed pro 405 pistons are zeroed with he deck I put it at TDC and it looks very close to the top. As you can see in the 4th pic. I think it's gonna be a good short block to build on to. Im gonna redo the heads and check the cam but I may not have to do to much.
 
Yeah, I don’t think anyone would O ring a block for those low compression pistons. I think there were different pistons in there at some time someone swapped those pistons in there
 
448Scamp said:
Yeah, I don’t think anyone would O ring a block for those low compression pistons. I think there were different pistons in there at some time someone swapped those pistons in there
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Nitrous motor?
 
448Scamp said:
Yeah, I don’t think anyone would O ring a block for those low compression pistons. I think there were different pistons in there at some time someone swapped those pistons in there
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There is a lot of weirdness with this engine.
 
RustyRatRod said:
That's unusual. I always thought you used copper head gaskets when o-ringing was done. What the hell do I know?
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I think this thing was just slapped together with whatever he had laying around. There is alot of weird things about it.
 
448Scamp said:
Maybe.
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It has some really large after market valve springs, with stock valves, adjustable rockers with hydraulic flat tappet lifters, low compression 405 pistons with head studs and now I find these o rings, idk what cam it is, it had a stick 60s 340 intake and a truck oil pan! ?
 
O-rings and copper gaskets for supercharged (roots) engines back in the day...
 
That's ready for a little bit of boost with some head studs. The SCE pro seal copper head gaskets are supposed to be good for street use. They have embossed silicone around the water passages.
 
I had a 40 over 340 block that was O-ringed without copper head gaskets.....Not sure what gaskets they were but they were not copper. Maybe special larger fire ring for O-rings? It was a nitroused motor according to the piston condition, ie clean crowns. Machinist said Nitrous cleans the piston crowns. Sold it to the 3rd guy who looked at it, the first 2 passed because it was O-ringed...? Take the wire out...
 
mygasser said:
i had a pair of head gaskets (came with other parts) for a 360 years ago that had a wire ring inside the combustion ring part of them. i guess they were for this purpose and they weren't copper. may have been felpro? could've been these, can't remember Fel-Pro Wire Ring Cylinder Head Gasket
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The 1008 FelPro is the most popular for high performance small block.

My SBM was built for 13-1 and has neen oringed. That was back in the mid 90's when gasket tech wasnt as good as today. After it was redone in 2007 it got 1008's.
 
Krooser said:
The 1008 FelPro is the most popular for high performance small block.

My SBM was built for 13-1 and has neen oringed. That was back in the mid 90's when gasket tech wasnt as good as today. After it was redone in 2007 it got 1008's.
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So the 1008 work with the o rings?! That's great to know thanks for sharing!
 
dartfreak75 said:
So the 1008 work with the o rings?! That's great to know thanks for sharing!
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You should call someone like SCE gaskets and talk to them. I'd hate to see you ruin an otherwise nice engine over a pair of 80 dollar copper head gaskets, wouldn't you?

If I were you, I'd calculate what static compression is.....I bet somewhere under 9:1 and save some coin for a blower. That engine was built for nitrous, or forced induction. A 6-71 stickin through the hood would be badass.
 
RustyRatRod said:
You should call someone like SCE gaskets and talk to them. I'd hate to see you ruin an otherwise nice engine over a pair of 80 dollar copper head gaskets, wouldn't you?

If I were you, I'd calculate what static compression is.....I bet somewhere under 9:1 and save some coin for a blower. That engine was built for nitrous, or forced induction. A 6-71 stickin through the hood would be badass.
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I was just figuring it up. I have to figure out my deck height because I'm pretty positive its been decked because them pistons are not. 050 under like they are supposed to be. But I got a 8.9 dc with a stock deck height and a 9.4 with a .02 under the deck. The copper gaskets are .070 so they would put me less than that a blower sounds pretty badass!
 
dartfreak75 said:
I was just figuring it up. I have to figure out my deck height because I'm pretty positive its been decked because them pistons are not. 050 under like they are supposed to be. But I got a 8.9 dc with a stock deck height and a 9.4 with a .02 under the deck. The copper gaskets are .070 so they would put me less than that a blower sounds pretty badass!
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or a pair of turbos and a blow thru carb to keep it under the hood?
 
dartfreak75 said:
So the 1008 work with the o rings?! That's great to know thanks for sharing!
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I don't know... when redone with 1008's the orings were removed by the engine builder. I had them take a skim cut on the heads and block and now it's about 14-1 compression.
 
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