utahws6

iTrader: (11)

anyone know what the deck height of the lq4 is?...is it the same as the ls1?

should be around .007 or less i believe

BackinBlack02SS

iTrader: (7)

Huh? The factory deck height of the LQ4/LQ9 block SHOULD be 9.240"

405HP_Z06

iTrader: (11)

Block deck height is 9.240". The piston deck height is typically .004" - .009" above the deck. The factory blueprint spec for piston deck height is .009" above the block deck.

utahws6

iTrader: (11)

piston deck height is what i was looking for..thanks
im using a lq4 shortblock with 62 cc ls6 heads...probably .040 head gaskets

think i came out to about 10.75 cr...does that sound about right?

405HP_Z06

iTrader: (11)

I calculate 10.83 with .040/4.039" head gaskets. Pistons .009" out of the hole. I'm assuming you milled the heads from the original 64.45 cc's?

utahws6

iTrader: (11)

yeah they were milled to 62...bout the time i hit enter to post i realized i should have posted that. who makes the .040 head gaskets?

405HP_Z06

iTrader: (11)

Cometic

utahws6

iTrader: (11)

figures lol..i have two brand new cometic head gaskets but they are for a ls1 bore

BackinBlack02SS

iTrader: (7)

Most head gaskets are .100+ larger than the bore they are advertised for. Might be worth a shot to measure the gasket size. Was this accounted for when figuring your compression?

utahws6

iTrader: (11)

i think i used 4.05 or 4.09 on the gasket bore size when i figured it.

BackinBlack02SS

iTrader: (7)

As long as the cometics you have aren't smaller than the bore, run em.

NemeSS

iTrader: (127)

ive measured up to .013 on a 98 engine
and a few lq4 have come in at .011

utahws6

iTrader: (11)

your talking about the piston deck height ?..if so and mine is that way it would sure help my compression. do u use a mic attached to the block to measure that?...

BackinBlack02SS

iTrader: (7)

You use a dial indicator attached to a "bridge" then rock the piston in the bore and get your average number in or out of the hole.

utahws6

iTrader: (11)

ok thanks thats kinda what i was figuring...

with the 6.0 block ported ls6 heads and moderate cam what am i goin to have to do to start it up with out messing anything up. ive just got the stock ls1 computer with stock tune.

5.3LJimmy

iTrader: (10)

It will run on the stock tune. The cam(depending on size) will likely cause a poor and unstable idle. As long as you don't have larger than stock injectors you will be okay to start and drive it. But don't try any WOT runs until it's tuned.

utahws6

iTrader: (11)

what about the stock #26 injectors...they will need to go wont they?...any idea what the injectors are off an 03 yukon 6.0?... course if they dont fit the ls1 fuel rails i guess it dont matter.

5.3LJimmy

iTrader: (10)

You will need to upgrade the injectors but you will have to wait until you can tune for them. I believe the 03 6.0 has 24lb/hr injectors and I don't think they fit the LS1 fuel rail. A mail order tune is an option if you want a good baseline and the ability to upgrade injectors now.

utahws6

iTrader: (11)

will the older ls1 #28's work or do u think im goin to need 33's?..
looking at something like the comps 228/230 .588/.591 114
1 3/4 pacesetters

utahws6

iTrader: (11)

heres another question... how much would have been milled from the heads to get from the stock cc to 62?... (243's) and how much is that goin to hurt my ptv?