elias_799

iTrader: (8)

i need to know what the factory ls1 crankshaft hp/torque limit is. i am currently building a low CR 347 and looking for maximum 600hp. and need to know if the factory crank will handle the power. i know this question has probably been asked before but the search did not show me anything i am looking for.

ABQ99TA

iTrader: (17)

The stock crank will handle 600 with no issues at all.

merlinn

iTrader: (8)

yea the crank will be fine

elias_799

iTrader: (8)

what is the limit ?, did anybody break one yet ? just curious

00Formula00

iTrader: (6)

Correct me if I'm wrong, but I thought I heard somewhere they were good to 1,000

00Formula00

iTrader: (6)

But remember, limit and safety are two totally different things.

elias_799

iTrader: (8)

what are the cranks made from ? cast iron ?

SOMbitch

iTrader: (8)

Yes cast nodular iron. I think you are safe to 700 easy.

Daryn

iTrader: (19)

i read somewhere in the upper 800's if your worried then get a aftermarket one

elias_799

iTrader: (8)

no i am not worried at all. i am just aiming for 600whp, and hearing that they are good for 800 makes me happy that i do not have to drop another 1000bucks on a new one.

thanks again for all your help.

1FastBrick

iTrader: (16)

I believe they have been run upwards of 1500 HP. How ever I am sure for that power level, They have been modified. Most of those guys don't want to say what they have had done but if you talk to any one of the high end Crank Grinders they will tell there are several ways to make them live at those power levels. Such as the Various types of heat treating, Nittrating, Cryo treating, Hard chromeing the Journals for better wear, Knife edgeing, Profiling The weights, pendualem cutting the weights, And so on.... There are so many different ways to modify a crank to make it live at higher hp levels But one of the big factors is balanceing the rotating assembly and keeping the weight of the rotating assembly on the lower side of things.

1FastBrick

iTrader: (16)

https://ls1tech.com/forums/forced-in...k-6-0-lit.html

Stock Factory Crank with A turbo spinning up wards of 7700 RPM

I know there is another one that was like 1450 but I can't seem to find it right now...

novaflash2002

iTrader: (51)

Ive seen plenty go 1200 hp

NonGoggleGuy

From what I've read, heard, and researched, the stock bottom end is good and reliable for more than 600lb-ft of torque.

MelScrilla

iTrader: (2)

thats good info, because i was planning to build a n2o motor and if the crank can hold 600rwhp that will be good. I was wondering what the rest of the rotating assembly is good for such as the connecting rods, i plan on replacing the pistons with forged ones.

lifeisgood

iTrader: (4)

rods and pistons forged and that more than most street cars need

NonGoggleGuy

You could probably throw as much horepower as you want at it, but the torque is what limits the rotating assembly. Torque is a force, horsepower just dictates how fast you can use that force. Of course, the stock lower end is reliably designed for 6000RPM, but you can throw more at it.

I could be a little off on that statement, so correct me if I'm wrong.

lifeisgood

iTrader: (4)

theres plenty of cars on the stock cranks making 1k hp

lifeisgood

iTrader: (4)

https://ls1tech.com/forums/forced-in...dy-kits-2.html

read

1FastBrick

iTrader: (16)

Most aftermarket forged pistons for this application will have a smaller .927 floating pin and be designed around a 6.100 or a 6.125 rod. There are some pistons with a 9.450 pin but you will have to bush the rod since they are floating pins. Forged rods are cheap enough now that upgrading a factory rod with better rod bolts and having them bushed for a floating pin application is just not worth it. I have seen stock rods fail in a complete stock application for Various reasons then there are guys that will tell you there putting down 500-600 at the wheels with stock pistons and rods. Some of those are in big heavy trucks too!