towerhand

I am currently having a 408 built, I have a GM iron 6.0 block, never been decked, i have a callies compstar 4 inch crank, a set of callies compstar 6.125 rods, the pistons are diamond part 11519 and my machine guy called me this morning and said the pistons are sticking above the deck height 15 thousands, is this normal. My machine guy wants me to step back and run a 6.100 rod, but the pistons are built for a 6.125, plus if i run a 6.100 rod that will cause more rock in the bottom of the bore, which is already a problem for this setup anyway. Has anyone out there run into this scenario before, any insight will be appreciated.

85MikeTPI

iTrader: (9)

.010-.015 out of the hole, sounds about right.. A .051 GM head gasket will give you a nice 0.036 quench, but since the iron block will grow less, you might just need to get a .055 to .060 cometic head gasket.

djfury05

iTrader: (30)

Yep normal.. your good.. but the bad part is that the machinist your using didn't know this! Is he not familiar with LS engines or something?

towerhand

In the area where i am at, not many machinist have, he is a good machinist, do you know what the main and rod clearances should be. We are going to have to take another 3 thou off deck height to straighten up, which will give me 18 thou total above deck, we plan on running a cometic 60 thou, does this sound right. Thanks

batboy

iTrader: (6)

Most LS engines have the pistons about .006" out of the hole. I dunno, .015" sounds like a lot. Might want to do a little more research.

85MikeTPI

iTrader: (9)

We're not talking factory parts here.