Ferocity02

iTrader: (59)

A few weeks ago I swapped in a 212/212 0.561/0.561 114LSA cam and stock 799 heads milled 0.022 to retain the factory 9.5:1 SCR. Before this the truck had an LS1 cam and stock 706 heads with a mail order tune. The tune has not been altered for the new cam and heads. It slipped my mind that the new parts should need a new tune. I have taken the truck to redline just a handful of times since the swap and was wondering if perhaps I have caused damage?

The new cam and heads aren't terribly larger than what was in there. The engine runs fine but has an annoying metal tapping sound coming from around cylinder 5 or 7. I pulled the valve cover and didn't see anything. No exhaust leaks. The lifters are fairly new with 0.075" preload. Oil pressure is great. No codes other than for the EGR which I removed. Could I have toasted a piston or rings? The tapping sound is hit and miss. I put it on jacks yesterday to investigate and the tapping sound was pretty much gone, then I noticed it again when driving home. The tapping seems to be at half the speed of the engine.

Thanks!

GMCtrk

iTrader: (27)

I highly doubt you hurt it. That being said, going WOT without it tuned was not the best idea.

Ferocity02

iTrader: (59)

Yeah it totally slipped my mind. I'm overly paranoid so I may to a compression test just to confirm.

andrew383

iTrader: (14)

Did you change valve springs also?

Ferocity02

iTrader: (59)

Yup, dual springs.

turbo-ls7

iTrader: (1)

Could be a wrist pin slapping the side wall had this happen to me a few months back on a 6.2 just a thought