Pewter'00Z28

iTrader: (2)

Heres a question for the nitrous junkies. I'm building a 409 for my Z and I was wondering, if you have forged pistons, and rods, is a crank really needed? I've heard stories of guys running stock cranks on forged set-ups pushing 700+hp. However these are 346 set ups. Could I use a 6.0 crank? I mean I could save some cash if this is possible.

Ben R

I've seen a mild 382 all-bore motor use the stock crank and run 9.60's. It's been running 9's for over 2 years now. Coming up on 3.

DERTY

I spray my 382 all bore on a stock crank with forged everything else. So far, that I know of, no one has broken a stock crank yet.

SDB

iTrader: (7)

the stock crank is probably the strongest part of the LS1 engine...many tuners use the stock crank for up to 600-700 hp motors, then they may use the Lunati or the Moldex. LPE build stage 1+ turbo stock displacment vettes with lunati pistons and rods, but will reuse the stock crank and get 600+rwhp on auto cars...and they are always overkill in terms of durability.

SDB

strokedls1

iTrader: (1)

You can't build a 409 without a stroker crank. An iron 409 is a 4.040 bore with a 4" stroke crank. Am I missing something? With a stock crank it would be in the 370ci ball park.

Big Mike

iTrader: (4)

I'm running 9.40's on a stock crank. 700+rwhp and 800+rwtq.

Pewter'00Z28

iTrader: (2)

I see all these guys running stock cranks on their 346's do you think the 6.0 crank is just as strong?

taqwache

a 6.0L crank will be just fine and will hold the same amount of power as the LS1 but it is heavyier. i sold mine to get a LS1 crank, had it offset ground to a 3.71 stroke, and put it in my 6.0L block. i will be spraying this motor with tons of spray soon and i am confedent at least that the crank will take it.

z28mccrory

iTrader: (7)

What do you all think about the eagle crank ?
I have some TEA 2.08/1.60 6.0 Heads on the way, i have a stock 6.0 shortblock sitting here, and im in the process of trying to decide what pistons/rods/crank to use.
I was going to use Diamond Pistons, Eagle Rods w/ARP's, and an Eagle Crank.
I will probably spray 300 to it, what do you guys think.

mbaskett

I've yet to see any substantial proof on the weight issue. I've got 2 LS1 cranks and 3 6.0L cranks in my garage, and have weighed them all. They are all within 1/2 lb of each other with one of the LS1 cranks weighing more than one of the 6.0L cranks.

I think the weight issue isn't really an issue, since most of the weight variances has alot to do with how much bobweight had to be removed to balance the assembly.

Also, if there is any hard proof that there is a measurable (and consistant) weight difference, with the LS1's being lighter, it's because the main journals are hollow, so you're talking about a miniscule amount of mass, that's only in the very center of the pivot point. It would make more of a difference if the weight was out on the ends of the bobs or the rod journals, but being at the very center of the rotation, the parasitic effects are negligable.

I personally think the additional material in the center of the main journals makes it that much stronger, and you don't have the stress points of a 90* angle either.

Just my $.02

Vents

iTrader: (9)

btw, i've seen one broken. most likely a freak, but shattered none the less. it was in a 6L block where a rod didnt quite clear the pan, and contacted the crank. Matt, still have those pics up?

mbaskett

They are somewhere... I'd have to go track them down.... That crank actually looked like it broke because of extreme heat fatigue. The main bearing was spun REAL bad and the crank was discolered in the area around the break....