Lq9 crank

[mobileaudio25]

I just picked up a junkyard LQ9 out of a 2005 Escalade . My goal at first is 600whp until I have my new 9” rear put in. Then I plan on being around 800whp. I’m set on doing a turbo FI build.

I know I’ve read a lot here on the forums that the stock cranks are able to handle 1000+ Hp but I’m just a little weary of running the stock crank when everything else will be brand new. However if I could save $1k by reusing my crank I would like to do so. The machine shop doing my engine said I should replace the crank as well with that much power. He doesn’t have the motor yet. The Motor has 115k miles on it.

Should I just buy a new crank($1100), buy a new OEM gm crank ($500) or just run the stock crank that’s already in the motor? I would just hate to have everything running well and then have to do a complete tear down. Thanks

Max boost I plan on running is 18-20 lbs if I switch over to e85

 

[81cutlass]

Run the stock crank. There are many reports of people running fast on stock cranks. Local guy had a stock LS2 crank in a gen4 5.3 that ran 7.70 at probably 1400hp. I don't think iv'e ever seen a photo of an actual crank failure. Usually at the high 1400-1600hp range the stock cranks just start getting bendy and eat bearings.

The machine shop wants to make 20% commission (or whatever) on a new crank sale.

Don't overthink it, use what you have. An 05 is a gen 4 engine likely so it has the good rods. Use what you have, don't worry taking it to a machine shop. It ran in the car it came out of, no reason to think it won't run now.

 

[mobileaudio25]

Run the stock crank. There are many reports of people running fast on stock cranks. Local guy had a stock LS2 crank in a gen4 5.3 that ran 7.70 at probably 1400hp. I don't think iv'e ever seen a photo of an actual crank failure. Usually at the high 1400-1600hp range the stock cranks just start getting bendy and eat bearings.

The machine shop wants to make 20% commission (or whatever) on a new crank sale.

Don't overthink it, use what you have. An 05 is a gen 4 engine likely so it has the good rods. Use what you have, don't worry taking it to a machine shop. It ran in the car it came out of, no reason to think it won't run now.

Yeah I’ve talked to 2 machine shops now and both of them say I should put a new crank in.

He also said if I’m running forced induction he would recommend a line home and install main studs. He said he would also recommend a 3 or 5 angle valve job on the 317 heads. What do you think about that?

Another machine shop said main studs if you want them but never mentioned anything about a cable job. What do you think is necessary to build a good reliable turbo motor? Thanks for the help!