ssvolvo

Hi guys and thanks for you opinions beforehand,


I picked up an 01 LS1 Vette engine with 20k miles from a local Chevy dealer that was replaced under warranty for burning oil. I've already bought a heads/cam setup from Texas Speed. Stage 2.5 5.3 and 220R cam. This will be NA about 400hp. for a 3100lb. 4L60 daily driver.
Getting ready to put it all back together with the original pistons, new rings.
I had the block honed .0002" just enough for the new rings to seat. you can see where the block has moved around some...maybe settled. Engine machinist has told me not to worry about it he sees this all of the time with the Nascar LS2s he does that put out 650hp. So I'm not worried.
I've measured my clearances with good tools(not plastigage) and all piston/bore just under .002". My rod bearings are between .003-.0035". My mains are all about .0032" which I feel should be a little tighter than that.
My question is should I use -.001" mains and rods bearings in a block that has not been align honed/bored or just stick with the .003"+ clearances that I have now.
This is a budget motor that will never see spray or turbo just a street beater that is my daily driver taht I will certainly beat the crap out of and drags a couple times a year. If I get too much into it I might as well just buiy a new LS shortblock plus the fact that I'm a cheap b@stard!



Thanks, John

ssvolvo

9000th01ss

iTrader: (10)

If you're sure on the measuements I'd use the .001 under bearings. As long as the OD of the bearing is the stock size.

I thought nascar uses SB2 engines?

veee8

iTrader: (40)

Off topic but Chevy uses the new RO7 engine in Nascar.
If you are 100% sure the measurements are correct, I would play with the bearings to get them a little tighter.

ssvolvo

Just returned from the engine builder to have him check the rods. Ordered all .001 under bearings. Tells me they use all coated bearings for the Nascar engines. Mix and match std. and -.001 for custom clearances, depending on journal sizes. Also the coated bearings are smaller by -.0005".

Got to check out a Nascar LS2 engine he had waiting to be delivered to a team. It's stock 6.0 364 block with forged internals and 243 heads CNC'd by GM. Runs a carb and distributor. Low 600's hp. @7500 rpm. Keeps the price down for teams. I should have snapped a photo, really nice piece!

This engine he says is used for the CampingWorldEast series, not Cup.http://en.wikipedia.org/wiki/NASCAR_...ld_East_Series


Thanks for the help, John

veee8

iTrader: (40)

Right, similar to the old Bush type series. They keep the costs down for the teams. I think some of them are sealed up when they leave the builders so they can't be F'd with. Lingenfelter used to supply some the engines for a similar racing series.
Good call on the bearings, you will be happier and feel better in the long run.

veee8

iTrader: (40)

The cup cars use the RO7 powerplants.