MidnightDynamite

Plan for build is around 600 rwhp. Would I be better off forging the ls1 or starting from scratch with a LQ4/9? Balling on a budget but still want reliability.

Exidous

iTrader: (11)

How important is weight to you? If you are after "only" 600whp I'd say forged rods and pistons on the LS1. Stock crank.

HCI2000SS

iTrader: (2)

At that power level either one is totally fine

Rise of the Phoenix

iTrader: (27)

At that level, you can run a LS1 or LQ9 in stock form and be fine.

kinglt-1

iTrader: (26)

Save weight and keep the aluminum block.

MonmouthCtyLS7

iTrader: (6)

I would just throw rods and pistons in the LS1

Rise of the Phoenix

iTrader: (27)

I really don't see the point. There are countless non-forged LS1's out there running Procharged setups making far more than 600 hp and living just fine. As long as you have a good tune, you'll be fine. And if it does let go, you can always forge it then.

Exidous

iTrader: (11)

Unless the block has a new window. :-) I agree that a good tune will work well on a stock ls1 but having the safety of the forged rods and pistons is worth it...imo.

whatsa347

iTrader: (6)

Yup, I've seen way too many blow up around here to care, and that's WITH arguably the best tuners in the nation. You can control some things, fuel quality and other factors you cannot.

30th t/a

iTrader: (51)

Yea...If your running E85.

600rwhp and 93 octane is a time bomb just waiting to go off.

If your running 93 octane, a forged 347 is what Id do.
Id keep the compression 10.1, to keep the throttle response nice and crisp.
Low compression with forced induction makes for a slugglish ride in the low RPMs. Been there done that, Not fun!

The extra cubes of the LQ9 is offset by the extra 80lbs of weight. Again, Been there, done that.

kinglt-1

iTrader: (26)

If it lets go more then likely you will be buying a new block. Lol

MidnightDynamite

So down the road if I want say 800rwhp I'd be hard pressed to go the LQ9 408 route.

Exidous

iTrader: (11)

Forged ls1 will do 800rwhp on boost obviously. 383 even better.