My 400 Is Decked .015?

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Apr 9, 2007 | 08:50 AM

billybonesmusic

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From: chiefland fl

My 400 Is Decked .015?

my 400 is decked .015 im purchasing a rotating assy for it, i want to stay around 10:1 compression, i know that with it being decked .015 will make the compression slightly higher but i dont know for sure how to do the math, any math wizzez out there??? i need to know what compression pistons to buy, and also what gage of head gasket to get??? i value my brothers opinions here over my (machinest's) LOL

Apr 9, 2007 | 08:54 AM

Pete K

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Quote:

Originally Posted by billybonesmusic

It is difficult to say. Most engine builders bang the factory 9.025(ish) deck height down to 9.010. They just whack it down .015. Most aftermarket piston manufactures predict this and lower the piston crown approx .010 to allow for the decking.
The best way to do it is to take your best guess at the piston and do a mock up. Redecking the block may be nescessary to achieve your specific goals.

Apr 9, 2007 | 08:55 AM

Pete K

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Also, cc your heads now. The advertised cc of the chamber rarely matches the actual cc.

Apr 9, 2007 | 09:01 AM

billybonesmusic

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From: chiefland fl

right, the heads im using first are 041 castings, with 2.02's the machinest i bought them from said they were more like 62 cc

Apr 9, 2007 | 09:01 AM

billybonesmusic

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From: chiefland fl

should i use dish pistons?

Apr 9, 2007 | 09:03 AM

AGENT 86

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From: Summerland B.C. Canada

The more numbers you know, the easier it will be. Trying using one of these calculators to find what piston will work best.
http://www.performancetrends.com/download.htm#crc
http://www.empirenet.com/pkelley2/DynamicCR.html

Last edited by AGENT 86; Apr 9, 2007 at 10:14 AM. Reason: Dyslexia :)