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Head gasket selection help needed

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Old 03-05-2014, 09:55 PM
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74u
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Default Head gasket selection help needed

I'm running a 4.010 bore with TFS 225's. I'm looking for a .040" head gasket that has a 4.010 bore (or as close as I can get...not smaller obviously).

I'm starting with big dished piston and trying to recover as much compression as I can...I'm told if I mill the heads any more I will be risking intake/bolt alignment issues. Is there anything else I should consider?
Old 03-05-2014, 10:15 PM
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You wont gain much by going from .053 to .040. What chamber do you have on the heads and what dish do you have on the piston? I am guessing you bought a boost motor and are trying to run NA on it?

Standard HG size that is available would be a 4.030 x .040.
Old 03-05-2014, 10:33 PM
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I bought a already built running n/a car, then decided to change the combo and (while I'm at it) want to get as close to 12:1 as I can get.

The shortblock is by TSP
Diamond -10cc (zero deck)
59cc chamber

The calculator puts me right at 11.70 with a .040x4.030 gasket. Looks like that's bout the best I can do.
Old 03-05-2014, 10:34 PM
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That is the lowest I would go on thickness and yes, you are about done on the milling too. Make sure you measure your pushrods. If you dont, it wont be pretty.
Old 03-05-2014, 10:35 PM
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Originally Posted by 74u

I'm starting with big dished piston and trying to recover as much compression as I can...I'm told if I mill the heads any more I will be risking intake/bolt alignment issues. Is there anything else I should consider?
Sounds like you may be looking at a new set of pistons . . .

How much Static Compression do you have now and what SCR are you trying to achieve ?
Old 03-05-2014, 10:40 PM
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Originally Posted by ez2cdave
Sounds like you may be looking at a new set of pistons . . .

How much Static Compression do you have now and what SCR are you trying to achieve ?
While not ideal, I think my pistons will get me pretty darn close to where I need to be. 11.7:1 isn't exactly weaksauce compression for a DD pump gas car.

I started at 10.8scr before I decided to swap heads/cam
Old 03-05-2014, 10:42 PM
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Stay away from all reg out of the pump ethanol blends

pure-gas.org can help with that.
Old 03-05-2014, 10:54 PM
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Thanks for the link!

Bummer...closest station is 30 minutes in a direction I seldom travel.
Old 03-05-2014, 10:55 PM
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Stock up! Or use some of the ethanol additives like lucas or stabil. They will help.
Old 03-05-2014, 10:57 PM
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According to Frankenstein Racing Heads shell premium is the best ethanol mixed pump gas on the market
Old 03-05-2014, 10:58 PM
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BP premium is reported as ethanol free and can be as high as 95 octane.



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