Looking for a bit of input on what is typically required for prep'ing a new LS2 block (bare) for assembly. Are the cylinders finish honed, or do they need to be gone over (assume the use of file fit rings, please)? Line bore? Running a 4" stroke crank, is there a need for clearancing the block to clear the rods, etc (as is the case with the old school engines, for instance). Decking?

Thanks,
Mark

 

Mark,

See if I can help you out with this.

Get that new block vibratory stress relieved before you do anything else. Typical cost is around $120.

The blocks are honed from the factory but not for your pistons nor do they do a very good job of it. In any case, the bores will shift around a bit after the stress relief. This is a good thing. They won't shift around much more in service. Get the block honed with deck plates installed using the same head gaskets, fasteners you will use in the build up. Best to get a set of .005" over pistons to make certain there is enough stock to get a good round straight hole.

The main bearing holes must be checked with deck plates installed. Some new blocks will need the main bearing bores touched up. Some are fine as is.

Same holds true of rod relief notches. Some rods, Lunati Pro billet, will clear fine wthout notches. Some other brands need notches cut.

Decks vary from block to block. I would check your block after stress relief to see how close the four corners are. I deck every block that comes in here after sleeve installation. Almost all used blocks are way off in deck height front to rear due to the block shifting around as it stress relieves itself in use.

Steve

 

does gm put their motors together with out doing all this extra work?

say, i buy a new block from SDPC. does it need all this done to it? or does gm just throw it together like is, and put it in a new vette and warranty it for 100K miles?

 

Why do you think some new car engines have had piston knock problems and oil burning and some have not? It's pretty much luck of the draw. I'm one of the lucky ones, my '03 Z06 runs great and burns no oil.

If you want it done right for your own build up, follow my routine.

The factory has to do things with price in mind not to mention time involved in doing the work to closer tolerances.

Steve

 

Well, thanks a bunch for the info. How nice, you're in O'side, I'm right down the street in Carlsbad....

This is one of those questions I would have guessed the answer to before asking, but this is the first LS build I'll have done, so I was "hoping..." Hell, even the Bowtie block in my 69 needed a bit of work out of the box, not surprised that a production block would.

Mark