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Discussion Starter #1
I picked up some aluminum heads to put on my 468. I have a question about what head gaskets to run. I have a set of je 258277 43cc domes and my heads have 119cc chambers. I did the calculation for compression using an online calculator I found. I would like to stay pump gas around 10.5:1 or so. The block amd heads do not have an o ring groove. I figured I needed a head gasket in the .090 range. On a 4.310 bore what size head gasket can I run (O.D)? Can I run copper head gaskets? Where is a good place to buy head gaskets? I know summit, jegs, but am I just stuck paying $160 plus per head gasket (MLS)?

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At that CR, you don't need to spend all the $$ on MLS gaskets. And don't use copper without o-rings. FEL-PRO 1017 are more than able to handle it.
I just threw that P/N out there cuz I ran them in previous 468's. Fel-Pro has many more options (bore size/thickness) in that style gasket. They cost less than $80 per pair. Jocko
 

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I picked up some aluminum heads to put on my 468. I have a question about what head gaskets to run. I have a set of je 258277 43cc domes and my heads have 119cc chambers. I did the calculation for compression using an online calculator I found. I would like to stay pump gas around 10.5:1 or so. The block amd heads do not have an o ring groove. I figured I needed a head gasket in the .090 range. On a 4.310 bore what size head gasket can I run (O.D)? Can I run copper head gaskets? Where is a good place to buy head gaskets? I know summit, jegs, but am I just stuck paying $160 plus per head gasket (MLS)?

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Do you know the deck height on the engine at this point? I don't think .090 head gaskets are going to get you there with those 43cc domes, and are you certain of the chamber size on the heads? For example, a certain brand of low dollar heads shows chamber sizes that vary depending on where you read and buy them, some places stating 119cc, and others 115cc.

My quick calculation, guessing .010" deck height shows that you still would be closer to 11-1 with an .090" thick head gasket. Are the piston domes solid to where you can have them cut down, or is there a chance you can get some "correct" pistons instead of trying to drop a compression ration that is over 12-1 down to something you can run on pump gas? If you do end up using a super thick gasket, you probably will want to check port alignment, manifold bolt hole alignment and fit prior to putting gasket sealer on and just trying to bolt the intake on.
 

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At that CR, you don't need to spend all the $$ on MLS gaskets. And don't use copper without o-rings. FEL-PRO 1017 are more than able to handle it.
I just threw that P/N out there cuz I ran them in previous 468's. Fel-Pro has many more options (bore size/thickness) in that style gasket. They cost less than $80 per pair. Jocko
I don't think Felpro makes .090 gasket. Or anybody else for that matter, outside of Cometic and the copper gaskets.



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Better measure head chamber bore prior to ordering gaskets;) alot of alum heads wont seal at the firering if you order for m4 bore sizes
 

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Discussion Starter #6
The heads are Brodix Race-Rite rectangle port heads. They are advertised with 119cc chambers. The pistons are not in the block yet so im not sure of the deck height. The pistons are hollow domes so I cant shave them down. I wouldn't mind getting different pistons but I have these ones and the motor is a complete budget build just to get me one the water. Im currently buying parts and collecting for a bigger motor in the distant future. The pistons I have are used but they are EXPENSIVE new so I would like to use them. They are JE pistons that have been hard coated. Fel-pro doesn't have thick enough gaskets. I think that they only go to .053. If someone has a set of 10.5:1 pistons that I can trade them for the pistons I have then that would work too.
 

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The other thing I forgot to mention, that's also very important is that you are going to end up with .100" quench. I wouldn't build it that way.
 

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The other thing I forgot to mention, that's also very important is that you are going to end up with .100" quench. I wouldn't build it that way.
How would you build it? How do I determine quench? I have some pistons that came out of my other 468 that have L2465 pistons.
 

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Discussion Starter #9
Those pistons are speed pro 27.5cc domes and using this same program to determine compression ratio. I used 4.540 head gaskets (fel pro 1017) with .039 thickness and .010 deck and came up with 10.18:1. Would that set up have enough quench? Should I just stay with my old pistons? They are press in wrist pins not floating. I picked up a used set of Carrillo rods also for free so im going to use those.

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Those pistons are speed pro 27.5cc domes and using this same program to determine compression ratio. I used 4.540 head gaskets (fel pro 1017) with .039 thickness and .010 deck and came up with 10.18:1. Would that set up have enough quench? Should I just stay with my old pistons? They are press in wrist pins not floating. I picked up a used set of Carrillo rods also for free so im going to use those.

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Consider using the 1027 Felpro with the copper wire, specifically for aluminum heads.

If your old pistons are press fit only(no wrist pin locks), they will not work with the Carrillos.
 
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