new pistons

[westcoastdodge]

guys back around 5 or 6 years ago when i build my motor for the charger could not seem to find any decent +60 pistons so had to go with generic ones(in the pics)thinking of changing them to this type??whats your thoughts
http://www.ebay.co.uk/itm/151063721508?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[John_Kunkel]

What's your goal for final compression ratio? You can get +.060" hypereutectics with valve reliefs in several pin heights and they'll be lighter than the TRW's.

[westcoastdodge]

hi john probably around where the original hp motor would have been it has the 906 heads.i know it must be pretty low at the moment as the one fitted are quite a bit down the hole

[Challenger340]

You need an accurate CC volume on the Heads you will be using, to calculate the "static" Compression Ratio of any Pistons contemplated.
From there....
plug in your static C.R., with the timing events of the camshaft you are targeting, in one of the many "Dynamic Compression Ratio calculators available online.

I would suggest reading up on DCR(dynamic compression ratio), as it relates to fuel qualities, elevation, etc., etc., but generally DCR's ~8.0:1 are safe on 906 Heads(no quench), using Rod Ratios above 1.75:1.(slower away from TDC, but faster off BDC)

Hope this helps

[John_Kunkel]

Un-milled 906 heads typically have 88-90 CC combustion chambers.