LS1 piston question about oil usage
Just rebuilt an 2001 Vette motor LS6 block, for installm into my Volvo. I bought this motor from a Chevy dealer who had replaced it under warranty for using oil. The tech at the dealer who traced the usage before replacement told me that it was not excessive, about a quart in 1000-1200 miles. Said the owner rode them until they replaced the engine. Motor had 21,000 miles on it.
I tears it down and measures EVERYTHING. Crank mains, rods were quite loose for an LS1 so I used -.001 bearings. The piston/bore was .002". Had the block finish honed at a race shop who does Nascar LS2 blocks for the Camping World series. Said it was fine and I'm confident he knows what he is talking about. I re-ring it with Speed-Pro rings and put H/C setup, mild 220 cam and 5.3 heads from well known sponsor on this forum.
The car absolutely rocks. Big power for me and runs like a scalded skunk!
I still uses a quart in 1000 miles.
Trying to figure out why? The only thing I noticed when apart is the pistons have NO oil return holes in the oil ring lands. I thought this was kind of weird and should have replaced the pistons. They were like new so I left them alone so I would not have to rebalance the entire assembly.
Have about 3000 on the engine now and am quite sure it is all well broken in. Actually I am on my 6th
This has most likely been covered before. Any ideas?
Thanks, John
It's wierd, our 06 GTO pukes oil into the intake also but doesn't seem to use any oil. I am convinced it is a piston/ring problem and not the heads. Haven't gotten around to a leakdown test yet.
I wonder when and why GM went to coated pistons with oil return holes? Seems like I read a TSB on oil usage in Alldata.
Qwik video http://www.youtube.com/watch?v=II7PmaKv_XU



