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Deck height

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Old 03-05-2011, 04:06 PM
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I just figured it out my retarded engine builder ordered wrong pistons, he ordered the 1.627 compresssion height instead of stock 1.64 which would give you around a .02 stock deck height instead of my .04...
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Old 03-05-2011, 05:03 PM
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Originally Posted by pantera232 View Post
I just figured it out my retarded engine builder ordered wrong pistons, he ordered the 1.627 compresssion height instead of stock 1.64 which would give you around a .02 stock deck height instead of my .04...
I would do what Bob suggest, get the correct pistons and head combo. I gained 5mph with his cam and matching components. I already had a performance flat tappet cam with the similar duration specs. And as a plus it idles better and is twice as quick not just faster. I have not noticed it using any more fuel, unless of course you just run faster all the time
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Old 03-05-2011, 06:21 PM
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now you know why I asked that. they make pistons with so many comp. heights that it happens more than you would like to think.
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Old 03-05-2011, 07:06 PM
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Im shooting to put the dome pistons in it. but if not how much can we get away with taking off the block?. If we take of .04 I would have zero deck height.

How much dome piston can i fit with the 781 heads?
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Old 03-06-2011, 09:13 AM
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I like .010 in the hole. That way you can set the quench nice and tight.
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Old 03-06-2011, 04:04 PM
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Blue thunder so .01 dech height with the flat piston, if i go with a dome piston and dont shave block what size dome to run would it be a .01 dome or larger
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Old 03-06-2011, 04:25 PM
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You need to know the actual cc of the head, the cc of the gasket you are going to run, the bore and stroke you are going to run, how far in the hole you want the piston to be and the ratio you want achieve. Then the piston company or Bob can tell you the dome height you will need to get there.
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Old 03-06-2011, 06:41 PM
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The .010" in the hole will allow you to run a tight quench with a readily available head gasket. You want your quench distance to be round .040" so if you were .010 in the hole you would go with a .030 head gasket to get the .040 quench. Quench is an important distance to set properly as it prevents detonation. The dome of the piston has nothing to do with quench. You choose the dome to complement the head and arrive at the desired static compression ratio. As gpm stated above. Ask your engine guy to cc the heads and we should be able to point you in the right direction from there concerning dome height.
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Old 03-06-2011, 06:42 PM
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Should have cc of 781 head tomarrow.. .the stroke is stock bore, bored out .040, stock 330hp is .02 deck height..

i wonder what deck height and domed pistons a 454 mag runs?
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Old 03-09-2011, 07:20 PM
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I got cc of heads today there 781 heads with 115cc.
the 454 is a 4.29 bore and 4" stroke
The lowest forged domed piston i found was from speedpro it was a 13.8cc dome, they had alot of 18cc domes. 13.8 dome volume would put me around 9.1 compression ratio, I only have around 91 octane readily available. Im going to try to run a compressed gasket around .038 will this set up be save regarding piston slapping valves/head??

Does anyone recommend a thinner gasket?

Thanks All
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