Wolftrk99

iTrader: (5)

Wasnt the l33 the 5.3HO??

dobsnek

iTrader: (1)

Crap so I'm still confused on the pistone I have. I don't want to have the wrong mill if I have a certain piston if that makes sense. Don't want to leave the truck down longer than I have to if the heads aren't cut right. I will be running a method system so wouldn't I want in the 9.5 to 10.0 cr range?

1FastBrick

iTrader: (17)

Yes and no. I have never found any documentation that they refer to the L33 as an HO motor.

It was in the trucks.

There was also a 5.3 HO gm crate motor but it was not as powerfull.

1FastBrick

iTrader: (17)

LM7 will have a dish poston. -8cc

65cc chambers will be in the 9:1 compression range.

dobsnek

iTrader: (1)

Stupid auto correct. Pistone and method system. Pistons and meth system is what that was supposed to be.
Thanks 1FastBrick

1FastBrick

iTrader: (17)

Your welcome

JordanH

iTrader: (16)

No around 64-65cc on all 243/799 castings.[/QUOTE]

But he said they were milled 24thou... And they are worked from LME, so really the CC could be any size? But a stock cc 799/243 milled 24thou should be in the 59-60cc range.... As long as LME didn't work the stock combustion chambers

dobsnek

iTrader: (1)

Yes the post that the heads are on are 65cc. I thought I read somewhere that a bigger combustion chamber is better for turbo applications.

JordanH

iTrader: (16)

ehhhh, it's really just getting the compression ratio you want... That's why people use factory 317 heads to get the compression down some on factory motors, 317's are 72cc... And they flow just as well as 243/799 heads, but with larger combustion chambers. The diamond Pistons I just purchased will be around 9:1 with a 317 head and around 9.6:1 with 243/799 heads, which is what I'll be using.

1994Vmax

iTrader: (4)

See I agree but I should have snapped pics of the engine I just had to deal with. 2007 Gen IV with AFM and 799 heads. Truck was auctioned off from a utility company after the original engine was deemed worth more to repair than the truck was worth. Owner got it with one head off and there was some scoring in the one cylinder and a lifter had eaten the cam...... The kicker though.... dished pistons. No flat tops in that thing and it was a standard bore Gen IV 5.3 out of a truck that really didn't have a ton of miles on it either. Did someone pull the pistons along its life and reinstall the incorrect dished slugs? Maybe..... maybe it was an oil burner on warranty and the dealer was too lazy to get the right pistons..... I don't know. But I do know that 2007 is a bastardized mess of a year that I hate dealing with in any faction.

The pistons looked awful in it too.... they were all pitted on the face... like the surface of the moon. I get to see some strange things from the depths of my buddies engine shop lol. The cheap *** owner had him hone the scored cylinder ( it still didn't clean up) after he had the heads redone, put on new rings and he put it together himself at home. Then had a hell of a time getting the afm solenoids or VLOM because he didn't want to pay for it.... some peoples children. It's got a gen iv 4.8 cam in it because he took that from me.... oh well lol.