LD9 Cranks: Knife Edging and Weight Reduction! - Performance Forum
Discussions about performance modifications to j-body automobiles which do not involve any kind of forced induction or nitrous. Topics in any way related to turbo or supercharger should go in the Boost forum, and nitrous topics in the Nitrous Oxide forum.
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You can Litter it your self... just need a angle grinder...
its the Balancing itself that is important.
John.... how did they break?! Low oil? Rod Knock? I have never heard of a Crank Breaking save for bad castings...
Chris
I do not remember. This was posted on the ORG many years ago. The stock one I think broke at the crank pulley (I truly think it was freak thing). The other one was manking good power and broke.
I had talked to my machinist about lightening and modifying the crank like you have pictured. He told me through his experience it doesnt matter what make the crank is, taking off that much will drastically reduce the life of the crank. I trust his judgment, when hes not working on engines hes racing, so hes tried a LOT of combos. He said a crank modfied like that will only last a few races before it gives out or wears out the bearings. That being said he said there is a sweetspot where you gain power but still retain the longevity you just need to play with it. Just thought Id throw that info out there.
Re: LD9 Cranks: Knife Edging and Weight Reduction!
I had talked to my machinist about lightening and modifying the crank like you have pictured. He told me through his experience it doesnt matter what make the crank is, taking off that much will drastically reduce the life of the crank. I trust his judgment, when hes not working on engines hes racing, so hes tried a LOT of combos. He said a crank modfied like that will only last a few races before it gives out or wears out the bearings. That being said he said there is a sweetspot where you gain power but still retain the longevity you just need to play with it. Just thought Id throw that info out there.
no offense but i doubt the guy you're referring to as ever raced a 2.4 or quad powered car before, if he as... fine. but i doubt it. so i take what he says with a grain of salt. sorry.
this guy actually has built LD9 ad quad motors for cars that actually have raced. they last just fine for them. and stock cars are beat on pretty badly, i would not have any regrets putting this crank in my car for street driving. if it lasts, great... if not then i guess i found out what not to do. LOL
i am going to find out if its really worth it or not though.
I must confess... I feel like a monster!
Re: LD9 Cranks: Knife Edging and Weight Reduction!
I had talked to my machinist about lightening and modifying the crank like you have pictured. He told me through his experience it doesnt matter what make the crank is, taking off that much will drastically reduce the life of the crank. I trust his judgment, when hes not working on engines hes racing, so hes tried a LOT of combos. He said a crank modfied like that will only last a few races before it gives out or wears out the bearings. That being said he said there is a sweetspot where you gain power but still retain the longevity you just need to play with it. Just thought Id throw that info out there.
no offense but i doubt the guy you're referring to as ever raced a 2.4 or quad powered car before, if he as... fine. but i doubt it. so i take what he says with a grain of salt. sorry.
No offence taken. He hasnt worked with many quads before but he has worked with a wide variety of engines. Anyways just food for thought. Hope for all our performance sakes it works out for you.
Re: LD9 Cranks: Knife Edging and Weight Reduction!
so the other day on the way to pick up wades car in wisconsin we stopped at the guy's machine shop...
got a look at the gutted crank first hand. my jaw dropped.the work on this this is absolutely stunning. you can definitely feel the weight difference as well. like night and day. i dropped my crank off to get worked on, although i wont be able to afford to have it done just yet. he was cool with me just leaving it there for awhile til i gathered funds. i also need to get him a 2.3 crank gear yet.
the guy is cool as hell, an old guy that really knows his stuff. believe me, some of the things he's been doing over the years makes the stuff we've been doing look like child's play. be on the look out for a post in here with some more goodies....
here's the pics i got. the stock crank on the right is mine:
and here's some of one he had only one side finished on. was still in the lathe....
I must confess... I feel like a monster!
Re: LD9 Cranks: Knife Edging and Weight Reduction!
