Shiftslow

iTrader: (9)

I've been looking into 370ci iron blocks, forged ls2's, ls3's, and 388ci Dart SHP blocks. The car is a 2002 Trans Am car weighed 3360 with an iron block 408 no driver. So far I have a Huron v2 t6 kit with an s480/96 1.32 a/r cast turbo and an LJMS 233/239 cam. I'm looking to get a solid 800-950hp 15-20psi out of this block and have the car capable of trapping at 150mph. Do I need to spend the extra cash on the dart block with big bore or will one of the other blocks get me there with the turbo mentioned above?

LS6427

iTrader: (2)

Cheap iron LQ9 block. 390ci fully forged for only 850 hp.....

If I had to do it all over again....or when my iron 390ci goes boom......I'm getting a 6-bolt LSx iron block and having RED sleeve it with Darton sleeves. Best of the best.

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Game ova

You can do what you're looking to do with an aluminum 365 easily. As well as enjoy the weight savings.

gametech

iTrader: (1)

If you just randomly selected a block from any LS based block available, you would have over 90% chance of reliably meeting your goal. Most of them would do it with stock bottom ends. If you spend the dollars for the Dart, you really need to up your goals.

stevieturbo

Just pick any factory block, they can do it no problem when built correctly.

If your budget permits for a better factory block...ie LS9 then go for it.

No need for heavy iron, but they're usually cheaper than Alu.

Ratical

iTrader: (82)

If it were mine I would go with an L33 aluminum block 5.3 from an 05 or newer truck. Thick walls, lightweight and you can easily achieve you goals on all stock internals. I see them all the time selling for under a grand complete.

Shiftslow

iTrader: (9)

Picked up a mint ls1 short block for $300. Going to have the block forged put some TFS/PRC as a cast heads on it and call it a day.

TrickFlowTech

If you go LS1, the 1999-2000 LS1 block is the preferred starting point. It has solid main webbing and better rear oil galley passage. The 1997-1998 LS1 blocks have solid main webbing, but less desirable oiling.

Shiftslow

iTrader: (9)

I see, the one I picked up came put of a 2001 TA.

stevieturbo

2001 could well be an LS6 block.

rpturbo

iTrader: (47)

Can you tell me what the actual difference is? I was under the impression the LS6 just had (maybe better heads) and the LS6 intake and camshaft. I know virtually nothing about the ls6, so I just thought it was a cam/intake package basically on a LS1 block.

293LSX

LS6 has better bottom end bay to bay breathing than the early ls1's. Some say they are stronger because they where cast differently but don't quote me on that. My vote would be for a 408 half filled lq4 block with some afr or TFS heads. Could get you where you want to go easy.

Game ova

His goal could easily be met without the half filled 408.... or the aftermarket heads.

SLOW SEDAN

iTrader: (13)

Don’t need anything fancy to trap 150 or even 160 especially at that weight, stock 5.3 will do that. At most a forged rod/piston in any stock block will be good insurance.

fastlt1

iTrader: (4)

Is dart shp or lsx stronger

gametech

iTrader: (1)

I am of the opinion that neither will do a good job of containing broken rods at full power. The relevance of that comment being that if you are pushing enough power to worry about the strength of either block, something else will break first. At a certain point it is far more economical to just go BBC.

gnx7

iTrader: (28)

I recently read that the Dart SHP block is made from an inferior steel compared to a Dart LSNext block. In essence under 1000rwhp all you need is a stock production block. I wouldn't even run a forged crank. LS2 would be my choice.... $1133 delivered new from Summit.

Rebelfromva

summit has ly6 iron 6.0 for around same price