Bink

I plan on installing the Grand Am cam(239/251,0.570",106 lsa) and the SDPC LS6 CNCd heads (milled 0.055")over the winter. The heads ,cam etc. were ordered 3 wks ago. SDPC says I'll need to flycut the pistons .050-.060". Should I have the stock pistons cut or would I be better off going with after market pistons?

Car has 8000 miles on it and will be re-ringed by dealer soon. Dealer will let me send out pistons for flycut during re-ring. Help!!All ideas and opinions greatly appreciated. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

<small>[ December 07, 2002, 03:00 PM: Message edited by: binksz06 ]</small>

LS1derfull

The extra rpm you will need to turn with that cam, will be hard on stock Hypereutectic pistons. I would plan on turning that motor to 7200rpm with that cam, this rpm will be safer with Forged piston like JE. Lighter weight of JE will prolly require rebalance of crank, but will increase higher rpm reliability of piston, rod, crank and bearings. If this sounds like too much work for you than i would choose smaller better suited cam instead. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

Bink

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">If this sounds like too much work for you than i would choose smaller better suited cam instead.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">LS1derful- Thanks for the reply and info.I'm going to bolt it on and play with it. I'll keep the Rs below 6800. Only will probably put 3000-4000-street miles on it (max) then I 'll need to decide- Balanced forged rotating assemby or Darton block?? Decisions...decisions. Thanks again for the excellent advice. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

<small>[ December 08, 2002, 03:18 PM: Message edited by: binksz06 ]</small>

Bink

ttt

rich

just got back from the PRI show in Indy. Lunatti has a set of forged 3.898 bore pistons. I am not sure if they are 400 grams like the stock pistons. If they are you wouldn't need to rebalance the motor. ARE sells a stock forged piston. It is a ross brand which is a good piston. You would have to bore the engine .005 or so over for these pistons but they weigh 400 grams and don't have to be balanced. If want you could call any sponser and order a custom set of pistons from any manufacture you would need to tell them the diameter of the piston, weight,ring size how deep of a fly cut,wrist pin diameter and pressed or floating, flat top or dome, if dome how many cc's,and compression height which is from center of wrist pin to top of the piston not counting the dome.Hope this helps you.Rich

Bink

rich- thanks for the info! <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

Jelly

Give me a call at Diamond Pistons. We have a stock replacement piston for the LS1 that has the valve reliefs you are looking for. Our pistons weigh the same as the stock piston so you will not have to rebalance. The part number is 11500. You can order them from us or one of our dealers, Thunder racing, LG Motorsports, Futral Motorsports or JPR.

Thanks,
Chris Gelineau
Diamond Pistons
877-552-2112 toll free