Quote:
Originally Posted by RSSRTOY
PISTONS NOW YOUR OPENING ANOTHER CAN OF WORMS.
LQ9 04 FIRST DESIGN #88894241 HAS A UPPER COMPRESSION IS 1.5MM THICK FOR 1ST DESIGN
LQ9 04-07 & LS2 04-05 SECOND DESIGN #89017478 HAS A UPPER COMP RING THAT IS 1.2MM THICK WITOUT 4 DRAINHOLES AT 3RD RING LAND
LS6 04-05 89017581
IF YOU WANT MORE ILL HAVE TO FINISH WED AS ITS TIME TO GO HOME  |
Oh, wow. RRSSRTOY. This seems to say that the 2nd edition 2004 (in GM talk that means 2nd design released that year), and all subsequent LQ9 and LS2 pistons are identical.
Since we already know that the cranks and rods are identical, this basically says that an LS2 and a later model LQ9 are identical engines except for:
- LQ9 has lower compression ratio due to larger chambers
- LQ9 is cast iron block versus alloy block
- LQ9 stock cam is much milder than the LS2 stock cam
Notice I said "stock" cam.
IF someone is contemplating changing cams anyway (and what redblooded American would NOT be contemplating that), it makes sense to buy the much less costly, and much more available, LQ9 as the base for the cam swap!
With an LS engine that is not yet inside a vehicle, the cam swap is remarkably easy and quick.
Then, how hard is it to remove that complex, "structural" oil pan and change the connecting rod bolts to ARP bolts? IF there are no subtle glitches there to be avoided, changing those con rod bolts takes out the ONLY weaker link in the entire engine. 6800 rpm is very feasible then. People have been doing 6800 rpm on the dyno with this engine, but have been hesitant about keeping that sort of rev limit on the street. The ARP connecting rod bolts change that.
We are talking about a LOT of power in this scenario.
05/06 SSR owners: are you listening?
Jim G
