Have buddy with paxton supercharged lt1 stock displacement.Its had some mild head work,blower cam,forged lower compression pistons.Not sure if he is on stock rods but he is on stock crank. He broke his crank showed me it has nice crack thru it. Is this common .I am a bit worried as currently am doing up a long tube/LE2/CC305 and 1.6 pro mag with alll the little bolt ons and have a zex 125 wet kit also to install. So is my crank on borrowed time?
I thought have read of lots of lt1 guys with similar engine mods to what I have planned running stock crank. And can't remember reading many posts of broken stock cranks. I was more worried about the stock pistons.
Its not the end of the world if my engine goes put in forged stuff ,no stroker lt1 parts are pretty cheap and easy to find used on the boards but mostly curious.
I was thinking maybe just a flaw in the crank.He has made 450 engine hp and was only running like 5 to 6pounds on the paxton. Car did have enough power to break his rear end on first and only drag pass its ever had but its a six speed and he was on et streets.

 

I am pretty sure the stock crank is suppost to be able to handle around 500hp. I am not sure so someone else will have to chime in.

 

ChevyTuff you are running very similar setup to what I want ,zex kit and cam and headers only thing missing is heads I think in your sig so if you haven't had any trouble then think I should be ok. I wouldn't be using my spray much and am deciding maybe should just put it on my 99 ta and not bother on my 96vert. A heads/cam/headers bolt on lt1 should be pretty decent power anyway.

 

I am still planning on doing some ported heads this winter and I havent had a doubt about the stock crank. I have sprayed my car 4 times and still no problems. You should be fine.

 

I wonder if detonation did the crank in on the paxton car..??
Can detonation kill a crank as well as pistons?

 

I am thinking thats what happend. When you have detenation it doesnt allow the piston to reach its peak and it gets forced down when the crank hasnt made it all the way around yet, thus, putting more stress on the crank. Detenation can also be a pistons worst enemy. I am willing to bet this is was happend with your buddy's engine. Someone please correct me if I am wrong about any of this. Peace, Dustin.

 

My stock crank is holding strong after 4 years of spinning to 7 grand. On my lt1 heads it made 425 rwhp(through 9"/4.71s) and on a 75 shot made 505 rwhp and 565ish rwtq. On my new heads I'm making 476rwhp all motor. I say its doing pretty good. Make sure everything is right thought..the higher in hp you go the more expensive a simple mistake(like tuning) can be.

 

Detonation will kill a crank as well, knocks the bearing (rod bearings) out of their "crush" as some people call it .

As long as the oil is there you can run a stock crank pretty hard. But other factors can kill too like mentioned (detonation). I allways hear 500 hp from the people that really know what they are talking about.

 

I was planning on a rebuild in a year or few. Was going to do a 355, with a le2.5 package, and a 150-200 shot on forged pistons etc....The stock crank wouldn't hold up to that?

 

Ive said this many times before..but here it is agian. There's a car club that was in car craft that was a bunch of street driven 10 sec chevy II's. They all had small blocks with forged internals but they would get there cranks from the lt1s because of there strenght. These were some pretty stout small blocks spraying 250 hp on some of them. I will be running the stock crank on my new setup and am not worried at all.

 

Everything mechanical can break, just because one blower car cracked a stock crank does not mean they are weak. The whole LT1 bottomend is pretty tough, keep her detonation free and well oiled and you should be fine. I have seen some cam/blower/n2o dyno charts for b-bodies putting over 600/600 to the friggin wheels with forged piston, stock crank and rods, another b-body runs 10s on head/cam/blower/nitrous, are these normal no but show the extremems it can handle without breaking if you have the stones to push it that far.

 

that aint no ****, them b-body boys make those cars run hard
and they weigh in close too 4000lbs

 

I put down 506 rwhp 600 rwtq on stock heads and just upgraded to ported heads and intake. Forged pistons and rods, stock crank. Pull lots of timing for the spray and dump in a gallon of xylene or toluene to really help resist detonation and you're good to go.

 

I run the numbers in the sig with a stock crank and 2-bolt mains with ARP Bolts (not studs). I still have good oil pressure and have been running it for over 3 years now. Not sure on the rwhp as I have a th400 but I have sprayed it quite a few times on the 200 hit and will be in the 9's once the cold weather hits and I fine tune the hit.

 

IMO...a stock crank in conjunction with some good studs and a good line bore can take more punishment than most on this board will even get close to.