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The Gear Rower
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Discussion Starter #1
As it states above, just wondering if there is a large difference in the CD between the 2 types of pistons? I have 1.215" CD on my nitrous slugs. could this piston be machined if there was enough ringland and the rest of the piston was still thick enough to support the planned boost?

thanks!
 

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Please clarify, I assume CD is compression height?? We need more information such as, solid or hollow dome piston, distance from piston deck to 1st ring, chamber CC, bore, stroke, chamber softening, fuel type, power goals, etc. There's a little more to it than milling off the dome if it is going to make a decent amount of power. The 1.215" CH is in a usable range depending on the other factors listed above.
 

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The Gear Rower
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Discussion Starter #3
shit sorry.CD is compression distance

switching to turbo from nitrous. 4.045 boer, 3.875 stroke, chamber cc 59, piston is .010 in the hole. top of piston to top of first ring is 0.330" , c16, flat top pistons
measured the actual thickness of the piston it is 0.230" in the center(hope that makes sense)
sorry i don't know what chamber softening means? unless that means working the bowls to reduce the compression ratio from 11.58 to 10.0ish
i want the setup to be able to handle 25lbs of boost, and 15-1600hp

i can tell you if i go from a .056" cometic gasket to a 0.080" gasket, and knock 0.030" off the piston it will achieve the desired compression ratio

I hope that helps ...thanks again!
 

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Personally I would leave the pistons alone and softened the chamber's to help get the CR down to where it needs to be. Softening the chambers cuts the quench pad areas on a parabolic dish to slow down the flame front propagation which makes the engine much less timing sensitive. You are basically trying to get it as close to a hemi as possible. The steeper the valve angle the thinner the chamber cross section becomes picking up combustion speed and efficiency, not what you want on a power adder engine. If you soften the charts 6-7cc and use the .080" gasket you will be around 9.7CR and it won't effect the balance of the rotating assembly. Call Curtis Boggs at Race Flow Development on having the chambers softened. Hope this helps.
 

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The Gear Rower
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Discussion Starter #6
thanks guys i apprecaite all of the info.

Turbo II, some of what you discussed, specifically about softening the chamber is something i was completely unaware of.

i will speak with the engine builder tomorrow
 
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