distantthunder

Can anyone suggest a replacement piston for DRP-12704? I was going to reuse them in my build but there is some damage to them so I am exploring other options.

Information is here.. http://www.cnc-motorsports.com/diamo...-280-bore.html

Build:

GEN VI 454
.030 Over
Stock Crank
Stock Rods
088 Heads, Cleaned Up
K-01-451-8 COMP CAM with Magnum Roller supporting hardware
Stainless Marine Full Exhaust
Holley 800 DP
Performer RPM Intake

Unlimited jd

iTrader: (5)

Sealed power l2399, little smaller dome, but you could mill the heads a little and gain the compression back. Good piston for the money.

Rookie

iTrader: (4)

JE/SRP 212135 I put these in as a replacement to my TRW 2399 stock Merc 420 pistons.
Great forged piston. They took a beating from a broken valve head. I was running about 122 cc heads.
http://www.cnc-motorsports.com/srp-2...-280-bore.html

http://www.jepistons.com/Catalogs/SR...dome_open.aspx

getrdunn

iTrader: (7)

You definitely have a lot of options however unless your planning for adding a blower or something down the road I'd just look into a set of affordable sealed power or KB performance with the correct dome to achieve the comp ratio your wanting. I would assume around 9.5:1. I just did a recent post regarding Pistons and rotating assm in general pertaining to the fewer and fewer actual manufacturers out there. Probe, CP, Diamond, JE... A lot of sister companies so to speak. No need to go through the whole list however if you research it much it won't take long to figure who's all doing what and for who. The diamond piston you linked to are a decent middle of the road piston. There are a ton of them out there from what I've seen. I noticed the ones you linked to are for a 6.315 rod? Also aren't the 088's 119 chamber? Regardless of which ones you choose just make sure you take everything into consideration from bore size, deck clearance, chamber size, squished gasket thickness, piston dome, etc. I didn't put a pencil to it but I think you'll be around +18-22 cc dome assuming the chambers are 119. You can look that up to confirm. Most all gm open chamber heads are 119.

Do a google for compression calculator and you can figure exactly within a point or two of what dome you'll need. That can sometimes dictate what piston you end up with otherwise as mention in above post you can have the heads milled some to help you get to where you want to be also. I use to do that all the time however would rather not if I don't have to. Just a surface to make sure there true. If you end up with a piston that's a tad to much dome you can always use a thicker head gasket or open up the chamber a few cc's.

Hope this helps a little for you.

I just ordered a set of autotecs for 565 build. Very affordable and good reviews.

distantthunder

Thanks for the input getrdunn, you are correct about the CR 9.5 - 10 : 1 is the goal. The listing on CNC-Motorsports is incorrect for the rod length (Good Catch!), I found the Diamond Catalog to confirm. I believe I am moving forward with the SRP-212135 as mentioned above, looks to have everything I need.

distantthunder

Looks like exactly what I need, Thanks! Going with the SRP-212135..

GPM

You may want to look at the Wiseco Pro Tru