02Vortech

Hey i see a bunch of LT1 cars that are boosted making 500+ whp on stock bottom end w/ alot of miles.... Im thinking about going with a forged bottom end but it appears that i dont need to. I would still like to rebuild the bottom end with either stock components and ALL ARP bolts/studs- or just some diamond low compression pistons....

So my questions-
Can the stock LT1 bottom end (crank/rods/pistons/rings) handle 600whp? (thats big enough for me i will probably only run 550whp)

IF it cant what components should i use to make it handle this the 600whp figure?

Is the block its self very sturdy? Do they last a very long, long time?

Your help is much appreciated- Chris

92zcamaroperson

iTrader: (1)

Im no expert, im just getting into forced induction myself. But I would say that while it might be possible it would not be reliable at all to boost a stock bottom end lt1. For best results and to get what your looking for you would need forged components specifically the crank. Also things like moly rings will be very important depending on how much boost you plan to have. Boost levels above 7 or 8 on a stock engine is where reliability will start to go down. Again I really dont know what im talking about. This is just my understanding.

Mkos1980

iTrader: (8)

We are building up a semi stock bottom end for a blower and our bottom end consists of a stock L98 crank polished and knife edged and ARP main studs. We upgraded the rods to Lunati Pro Mod rods and also upgraded the pistons to a forged Wiseco with a boost friendly 8:8:1 compression. We are having it internally balanced for reliability. Were hoping to run 12lbs

92zcamaroperson

iTrader: (1)

what kind of power are you expecting?

Mkos1980

iTrader: (8)

Well thats that bottom end. For the top end we went with a blower friendly LPE 213 cam. Although its set on a 112 LSA Lingenfelter said if has no overlap and would be a good cam to use. We stuck with ported and polished stock L98 cast heads with manley streetflo valves and also had the seats cut for comp 986 springs. Stock , but ported TPI intake will be on top. We figure prob low 13's stock and prob low 12's on boost.

Tony89

I recall reading some time ago in Car Craft an answer to a similar question. Marlan Davis, their veteran tech person I believe, stated that with the LT1, the pistons tend to go out before the rods and crank break. The specific example he mentioned was something about a guy showing up at a track with a stock bottom-end LT1, running too much nitrous to be safe. Something like a 300 horse shot. After the fifth or sixth run, the kaboom happened. Upon disassembly, it was discovered that the tops of a couple of the pistons had melted, but the rods and crank were OK. As one might expect, however, every single situation is slightly different. It's always best to have a healthy margin of error, in the form of beefier parts. When I get my set-up sorted out, I should be running 8 PSI or so through a stock bottom-ended 305. However, my heads are World Castings (a few extra pounds of iron in each one for better sealing), and my bolts are ARP. Ultimately, this is always a calculated risk, and stronger parts help neutralize an overenthusiastic right foot.

1bdbrd

iTrader: (1)

its all about the tune IMO. you can blow up a stock bottom end with less than 4 psi and less than 300hp. or you can have a good tune and make 450+rwhp. personally i want to push the bottom end. i want to run a set of TFS heads, a custom moderatly sized turbo cam, an lt1 intake and maybe around 10-12 psi on the stock bottom end. i would figure thats good for about 450-500rwhp or so through an auto. but the tune will HAVE to be spot on.