Mike Lee

I've got a LQ4 that I recently picked up CHEAP. Everything looks great except for some moisture that got into the cylinders while it was sitting. This is going to require a bore and new pistons. I have a '99 Sierra RCSB 4.8 truck that this is intended for. My long term intentions are to put the 6.0 in with a 4l80e and a 78mm single turbo. Currently the truck has a fresh 4l60e with good parts and fresh build. I have a LS6 cam that I intend to run in the 6.0 just because I already have it....I know....there are better cams but they cost $$$ which slows me from buying other parts.

Ok, enough with the babbling.....

Here's the real question. If it were you would you buy LQ9 flat tops or LQ4 dished pistons for the rebuild knowing I'm eventually going to boost it? The heads are stock 317's with a little work. I'm hoping to eventually get to 550-600 RWHP. I also already have a set of 60lb siemens/deka injectors.

Thanks in advance for the input. Whether or not I like what you have to say, I value all opinions.

Mike

GMCtrk

iTrader: (27)

Flat tops for higher compression

03sierraslt

iTrader: (22)

For those goals I would do flat tops also.

FFDP

iTrader: (2)

I'd upgrade the rods too, get some GEN 4 rods that are much stronger.

Mike Lee

If it had the press fit pins I definitely would, but it already has the bushed rods.

Thanks for the input guys, keep it coming.

Isn't there a slight concern of having too much compression when you start adding the boost? Also, would ARP head bolts be sufficient or would you spend the extra to buy the studs?

Mike

Camin00

I might have missed it but if you are running the stock heads you will only be around 10:1 compression and with a good tune I wouldn't worry about that. It will help give more low end tq while you are out of boost at low rpms.

Idk what others think but I bought the pro comp studs, they were like $70-80.
I would run ls9 head gaskets also.