rorric

iTrader: (19)

I have a lq9 with stock crank , forged piston and rods .. how much power would you or have you pushed with 4l80

93camaro_zzz

iTrader: (13)

Martin can correct me if I am wrong, but I am fairly certain he is still on a stock GM crank, and he just went 5.1X in the 1/8th. So you can push them pretty far. Usually you are going to lift the heads off the block before you break a factory GM crank.

JoeNova

Depends. With a turbo they seem to last 1300 or so flywheel HP (although there have been a few pushed to 1300 or so at the wheels). With a blower, less, since the belt is usually causing the crank to flex slightly.

rorric

iTrader: (19)

I am running twin pt 6266cea

speedfreak2685

iTrader: (12)

I flexed mine at 940rwhp with a f1a for what its worth. I know turbo guys like martin have taken them further.

2JZFC

iTrader: (26)

Stock48, 8.22 @ 164.7, 3350lbs. My math says ~1080 at the wheels!!

Sales@Tick

iTrader: (3)

I've been 138mph in the 1/8th at 3260# with a stock crank.

Shows roughly 1100rwhp.

mkvamso

iTrader: (2)

Sounds pretty similar to some local guys here
5.2 and 5.3 at 138ish
Somewhere around 1100 wheel, without an issue

I think it depends on the setup and tune as well
A stick car dropping the hammer off a 2 step will probably make a little more load to the crank than an auto car would
I wouldn't think twice about using one above 1000 wheel

stock48

iTrader: (17)

I just pulled my engine down to inspect and do pistons and rods. Was afraid to push it a 4th season lol. Crank actually passed a wet mag test and seems to be fine. Im still debating on if Im going to keep using it or step up to a K1 forged crank that I have here.

gpr

iTrader: (6)

This is a great topic as i was just debating on going aftermarket stroker crank, or keep the stock crank.

For some reason the wiseco pistons i was looking at get more expensive for the pistons for a 4" stroke crank, not sure why.

Anyway is there anything special you do to make these stock cranks live at this power? Obviously balance them to the forged rods and pistons. Then I'd assume run ARP main studs, ARP 2000 rod bolts. Anything else?

JoeNova

4" stroke pistons are more expensive because they are a complete re-design. The pin height has to be changed so that you don't have to run really short rods on a 4" stroke to keep the pistons from hitting the heads.

You could always send your crank out to Castillo in Cali and have it nitride treated.

gpr

iTrader: (6)

How much does nitride treating cost? Is this the same type of coating that eagle puts on their cranks?

I haven't seen one of the wiesco LS pistons. Have used wiesco's in lots of other applications with great success. I'm leaning toward using stock crank, with forged rods and pistons. Seems like a great option for strength and longevity.

Sales@Tick

iTrader: (3)

I say we keep proving the experts wrong that tell you that a stock crank won't last past 1000hp.



Watch now, I'll drive over my crank next weekend at Shady Side just for talking junk...lol.

BTW GPR, our 4" stroke Wiseco's are the same price as our 3.622" Wiseco's. Call for pricing if you'd like.

oscs

iTrader: (19)

Nope, Just hope for the best.

oscs

iTrader: (19)

Does anyone know if the stock cranks are heat treated? Or anyone know what the Rockwell # is?

Torqueshaft

As far as Rockwell #...

I seen a reference to it once when I was digging up some other stuff...

I'll see if I can find it.

Torqueshaft

Seems I remember it saying it was somewhere in the low 30's...

stock48

iTrader: (17)

I honestly think lose clearance and heavy parts/crappy balance is a big contributor to the death of stock cranks. Still however they are a cast part; that's what is kinda making me nervous.

stock48

iTrader: (17)

Yea that would suck! Im sure we are pushing the luck a little with them but the mag checked out good lol. How long will one hold the big power for tho is the question...

oscs

iTrader: (19)

That's pretty shitty. Has anyone ever tried to Heat treat the throws on a stock shaft? You can induction harden the throws for cheap and get a good 20 extra Rockwell out of it.