Well I have a 1994 b4c m6 with an lt1 and its on its last leg and I want to build a 350 ls style motor for it (7.0's bore 4.125 and 4.8's stroke 3.27)

My question is, i have a 6.0 LQ9 out of a 2001 denali and a few 5.3's and have an ls1 block available I was woundering if i can bore the blocks out and sleeve them with 4.125 inch sleeves? I'm pretty sure it can be done with the aluminum blocks but I dont know about the cast blocks.

Also does anyone make a forged 3.27in crank? I looked and i cant find one

 

IMO, that's foolish. Resleeving a block is expensive. And why limit yourself to a 350" motor if you're spending all that money and effort? You can make FAR superior power and torque with the same amount of money invested with more cubes, and you won't have to fight the combo to make it work.

 

You can bore out the iron 5.3 to 3.900 and go with a stock 3.62 stroke and get pretty close to 350. Basically make it an iron block LS1. Save you a bundle on the crank, too.

-Geoff

 

k well i'm getting an aftermarket block... but I still need to find a forged 3.27 inch crank does anyone make them or is there anyone that could make one?

 

aftermarket block = good choice. Why the need for a "non standard" crank? class racing, limiting size?

if your spending the money on somewhat pricey aftermarket parts, get the cubes out of it too. unless you want something to spin to the moon. BUT 7500-8000 rpm motors are hard on parts and valvetrain stuff gets expensive fast.

found a post (on a different forum) that said "Katech made a Sneak Attack LS7 which is actually 346ci, 4.125 bore and 3.24 stroke with an 8000rpm redline. Uses ls7 heads and dry sump oiling-580hp with 100 octane."

prepare to pay big $$$ for it.

OR use a standard stroker crank, keep it under 7000 rpm; make the same power and more torque for possibly less money. unless you want some sort of bragging rights. if thats the case, just tell people its a 350 they got spanked with. with an aftermarket block they wont believe you anyway. lol.

 

LSX block. The End.

 

There are all kind of options for motors on the LS series. You can do an LS3 and take it to 427ci, you can get an LS7 already at 427 and go up to 434, You can take a 6.0 and take it to 408 or even 415/418 cubes. Don't limit yourself on the LS1, look at all the options.

 

Best HP/$$$ N/A IMO is going to be a Iron 408. You just can't beat it. Now if your limited to a certain cubic inch limit then that's a different story.

If you want a streetable 500hp just put a D1SC on a LS1, then as time/$$$ allow build a low compression forged 408 to work with the blower and be knocking on 700hp+