|
Chinese forged cranks
#1644461
07/09/14 01:28 PM
07/09/14 01:28 PM
|
Joined: Dec 2013
Posts: 403
Romulus, MI
GTS340
OP
mopar
|
OP
mopar
Joined: Dec 2013
Posts: 403
Romulus, MI
|
Can anyone provide any insight on the lower end Chinese forged cranks? I'm looking for a 3.9 stroke crank with RB mains/2.200 rods and the only place that lists such a crank is Ohio crankshaft, I've personally never used any Ohio cranks but know several people who have with mostly decent results however Ohio will not have any available nor any 3.75 stroke cranks that could be offset ground to 3.9 for several months. I could offset grind a forged factory crank but would rather have a crank with fillets in the journals. I know K1, Molnar, and CompStar are supposed to be the best of the imports but since I will most likely be starting with a 3.75 and putting it right in the crank grinder anyway to offset grind and probably go .010 under on the mains Ive been looking at the really low end stuff like RPM, PEP, and Procomp so any potential issues with journal size, taper, and fillets would be a non-issue. Are there any other problems with the mentioned cranks as far as the raw forging, thrust faces, and ability to balance them without a ton of work? Also, has anyone had a lab test and verify the metallurgy on any of the Chinese 4340 cranks?
Application will be approximately 675 horsepower.
Last edited by GTS340; 07/09/14 03:35 PM.
|
|
|
Re: Chinese forged cranks
[Re: fishy340]
#1644466
07/09/14 03:03 PM
07/09/14 03:03 PM
|
Joined: Dec 2013
Posts: 403
Romulus, MI
GTS340
OP
mopar
|
OP
mopar
Joined: Dec 2013
Posts: 403
Romulus, MI
|
Quote:
You guy's do realize that Molnar,Scat 95%,K1 and a member here's cranks are chinese ?
If you're referring to me I thought I recognized that fact in my opening post
|
|
|
Re: Chinese forged cranks
[Re: GTS340]
#1644469
07/09/14 06:09 PM
07/09/14 06:09 PM
|
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
|
Quote:
Quote:
You guy's do realize that Molnar,Scat 95%,K1 and a member here's cranks are chinese ?
If you're referring to me I thought I recognized that fact in my opening post
Same here, with a Molnar and a few of the more pricey chinese forgings the companies stand behind the product ... because they are finished here, not over there ... and you'll get something that should be ready to run, the really low end, not so much.
|
|
|
Re: Chinese forged cranks
[Re: JohnRR]
#1644470
07/09/14 07:16 PM
07/09/14 07:16 PM
|
Joined: Dec 2013
Posts: 403
Romulus, MI
GTS340
OP
mopar
|
OP
mopar
Joined: Dec 2013
Posts: 403
Romulus, MI
|
Back to the original point of this post, disregarding everyone's opinion on what the best Chinese crank and if it's ready to run or not. IF a crank from one of the companies that has a reputation of being shyte goes directly on the crank grinder because it is going to be offset ground for more stroke and taking mains down .010 while it's there, therefore correcting any flaws, taper, out of round etc. in both rod and main journals. Would a PEP, RPM, or Procomp crank be sufficient in a 675 horse application? Or are there bigger problems with these $425 range cranks that grinding all journals, indexing, and correcting stroke will not repair such as major issues trying to achieve balance and bad thrust faces (which could be welded and repaired)?
|
|
|
Re: Chinese forged cranks
[Re: Moparpoor]
#1644472
07/09/14 08:50 PM
07/09/14 08:50 PM
|
Joined: Dec 2013
Posts: 403
Romulus, MI
GTS340
OP
mopar
|
OP
mopar
Joined: Dec 2013
Posts: 403
Romulus, MI
|
Quote:
I would just use a factory crank. Most low end cranks will need some type of work at your cost. Put the money towards high end rods and pistons!
So even though I perform my own machine work at no cost but time an old factory crank is better than a low end supposed 4340 Chinese forging? I'm looking for people who have dealt with these cranks personally and not just opinions. I'm willing to wait for Ohio if someone speaks up with merit but if I can achieve an equal piece by reworking one of the POS cranks I will
|
|
|
Re: Chinese forged cranks
[Re: GTS340]
#1644476
07/09/14 11:02 PM
07/09/14 11:02 PM
|
Joined: Sep 2011
Posts: 126
Howell,MI
Moparpoor
member
|
member
Joined: Sep 2011
Posts: 126
Howell,MI
|
Quote:
Quote:
I would just use a factory crank. Most low end cranks will need some type of work at your cost. Put the money towards high end rods and pistons!
So even though I perform my own machine work at no cost but time an old factory crank is better than a low end supposed 4340 Chinese forging? I'm looking for people who have dealt with these cranks personally and not just opinions. I'm willing to wait for Ohio if someone speaks up with merit but if I can achieve an equal piece by reworking one of the POS cranks I will
Yes! Not saying low end cranks wont handle the job! Just saying you can do the same job with a used factory crank for $200 or less! I have used source 4.25 rb crank was a decent piece. unfortunately needed a little work on the balance and small amount of taper.Crank was almost $650 with shipping not including machine work. I use factory cranks lately often in the few 451 low decks I have pieced in various forms. From all hand me down used parts to top of the line piston and rod combos. Just saying you can save the money and use it were needed!!
|
|
|
Re: Chinese forged cranks
[Re: Quicktree]
#1644477
07/09/14 11:27 PM
07/09/14 11:27 PM
|
Joined: Dec 2013
Posts: 403
Romulus, MI
GTS340
OP
mopar
|
OP
mopar
Joined: Dec 2013
Posts: 403
Romulus, MI
|
Quote:
let me get this straight, you want to build nearly 700hp and want to cheap out on the bottom end? I think it has been well documented here many times. by the time you get a low end crank spend the money getting corrected, balanced,straighten and what ever else it may need you could have bought a K1 or equal. why waste your time and money?
Let me start from the beginning again. I want a 3.900 stroke crank for RB with 2.200 rods. Only place to offer such a crank is Ohio crankshaft which they will not have available for several months along with 3.75 cranks. That leaves me with offset grinding a 3.75 crank to 3.900 as a viable option whether it be an aftermarket or a factory crank. A 4340 crank with fillets SHOULD be better than a factory 1053 crank with undercuts. Being that crankshaft grinding and balancing come at no cost to me other than my free time and any 3.75 crank I get be it a Bryant or a Procomp will be offset ground by ME. Question being, since no matter what 3.75 crank I get will be ground by me and have whatever dimensional, out of round taper issues corrected, are the cheap low end forgings comparable to the higher end (K1, molnar) aside from the finish machining that is irrelevant in this situation because it will be ground to achieve what I need, or are the forgings of these lower end cranks inferior. Remember forget about taper, roundness, blah, blah, blah, as I don't care if the journals as I receive it appear to have been finished by a 2 year old...it will be ground on rods and mains no matter what. Not trying to cheap out, just want to know if the machining/grinding is where the problems are or if it is a problem in the forging itself. That's it! Again, no matter what 3.75 crank I get will be "fixed" on both rod and main journals at no cost other than time away from family.
Think of it like this, why pay $200 for a std/std 440 crank only to grind down to B mains when you could get one with 2 spun mains for $20
Last edited by GTS340; 07/09/14 11:44 PM.
|
|
|
Re: Chinese forged cranks
[Re: GTS340]
#1644478
07/09/14 11:48 PM
07/09/14 11:48 PM
|
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
|
Quote:
Back to the original point of this post, disregarding everyone's opinion on what the best Chinese crank and if it's ready to run or not. IF a crank from one of the companies that has a reputation of being shyte goes directly on the crank grinder because it is going to be offset ground for more stroke and taking mains down .010 while it's there, therefore correcting any flaws, taper, out of round etc. in both rod and main journals. Would a PEP, RPM, or Procomp crank be sufficient in a 675 horse application? Or are there bigger problems with these $425 range cranks that grinding all journals, indexing, and correcting stroke will not repair such as major issues trying to achieve balance and bad thrust faces (which could be welded and repaired)?
Anything can break , if you are doing all that work yourself and can get one to do it on then go for it. It can't be any worse than a lesser material , 1053 twisted forging that is a stock crank, unless you hit a huge void grinding it down ??
|
|
|
Re: Chinese forged cranks
[Re: GTS340]
#1644479
07/09/14 11:53 PM
07/09/14 11:53 PM
|
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
JohnRR
I Win
|
I Win
Joined: Jan 2003
Posts: 75,043
U.S.S.A.
|
Quote:
Quote:
I would just use a factory crank. Most low end cranks will need some type of work at your cost. Put the money towards high end rods and pistons!
So even though I perform my own machine work at no cost but time an old factory crank is better than a low end supposed 4340 Chinese forging? I'm looking for people who have dealt with these cranks personally and not just opinions. I'm willing to wait for Ohio if someone speaks up with merit but if I can achieve an equal piece by reworking one of the POS cranks I will
Eagle would be on your low end I assume ? Dan Costello , Performance Only , did all the work you want to do to a circa 2003 Eagle Blem, stock stroke, RB crank I bought from Mancini for the Enginemaster build, it worked fine at over 700 HP for multiple pulls on the Pierce's Dyno.
I still have the crank for a 383 based build I may or may not ever get to ...
|
|
|
|
|
I've bought and used a bunch of there cranks over the years,(more than 12) I had one that was damaged by UPS in shipping(Crankshaft mounting flange was bent a buch :shock) and Ohio Crankshaft CO. took care of it at no expense to me 
I'm like Thumperdart, I've had several stock RB cranks offset ground to 3.91 to save money, I wouldn't buy a new one unless it was a bunch cheaper than a standard stroker crank like a 4.150 or 4.250 stroke though 