| Author |
Message |
woodsbuggy
Samba Member
Joined: December 15, 2007
Posts: 210
Location: NE Indiana
|
 Posted: Thu Mar 28, 2024 6:54 pm Post subject: Will a China crankshaft handle 275HP and 275ft/lbs? |
 |
|
I am in the planning stages for a 4 seater off road buggy and will be building a 2332 (94x84) turbo EFI motor. I will not rev over 6k rpm. I have an aluminum raised roof case and an Empi 84mm crankshaft, will this handle the power, or do I need to consider other options? I have only seen a few broken cranks and they were all welded stroker 90mm or factory German. Please share your experiences.
Thanks
Kenric
_________________
The empty can rattles the most! |
|
| Back to top |
|
 |
Chip 
Samba Member
Joined: July 19, 2008
Posts: 969
Location: Utah
|
| Posted: Fri Mar 29, 2024 2:42 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
| My limited experience says yes. Revmaster crank I purchased in 2011, held 275+ with slicks and 6500+ rpm launches just fine. It's recently been put out to pasture, and will soon enjoy the easy life pushing my children around in a mild(boosted 😁)2180 powering my bus. |
|
| Back to top |
|
|
Dan Ruddock
Samba Member
Joined: October 25, 2012
Posts: 3594
Location: Sarasota, in my adopted state of Florida
|
| Posted: Fri Mar 29, 2024 6:31 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
| woodsbuggy wrote: |
I am in the planning stages for a 4 seater off road buggy and will be building a 2332 (94x84) turbo EFI motor. I will not rev over 6k rpm. I have an aluminum raised roof case and an Empi 84mm crankshaft, will this handle the power, or do I need to consider other options? I have only seen a few broken cranks and they were all welded stroker 90mm or factory German. Please share your experiences.
Thanks
Kenric |
I am not surprised the 90mm cranks broke, the longer the stroke the weaker the crank. Plus, 90mm cranks need all T4 mains to have to have a chance for a long life. The new Empi crank design is better than the old one, taller checks for more cross-section strength. Hope your crank is not the chevy journal, they are weaker, less overlap. The more ridged the crank is the better.
There are many factors that determine how strong a crank is. Here is my 86mm Porsche journal crank with T4 CM, one of the strongest ever made. You can see how thick the cheeks are because of the narrow Porsche journals.
|
|
| Back to top |
|
|
Glenn
Mr. 010
Joined: December 25, 2001
Posts: 76963
Location: Sneaking up behind you
|
| Posted: Fri Mar 29, 2024 6:51 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
| Dan Ruddock wrote: |
| You can see how thick the cheeks are |
Link
_________________
Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"
Member #1009
#BlueSquare |
|
| Back to top |
|
|
chrisflstf
Samba Member
Joined: February 10, 2004
Posts: 3450
Location: San Diego
|
| Posted: Fri Mar 29, 2024 8:33 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
| If a 4340 chinese crank wont hold that much power, what other crank options are available? |
|
| Back to top |
|
|
Dan Ruddock
Samba Member
Joined: October 25, 2012
Posts: 3594
Location: Sarasota, in my adopted state of Florida
|
| Posted: Fri Mar 29, 2024 9:01 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
| chrisflstf wrote: |
| If a 4340 chinese crank wont hold that much power, what other crank options are available? |
The question is not if it will hold that much power but how long will it hold it. The flexing and bending will eventually cause small fatigue cracks which in time will cause a complete failure. The less it bends and flexes the longer it will last.
This is a pic of my 84mm DPR crank. Extra gusseted counterweight, drilled rod journals to increase the effectiveness of the counterweights, Porsche 2.165" rod journals. Cost me $550 back in 2014. Is in use now in my 61 bug.
|
|
| Back to top |
|
|
modok
Samba Member
Joined: October 30, 2009
Posts: 26790
Location: Colorado Springs
|
| Posted: Fri Mar 29, 2024 10:20 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
It'll handle 10 pounds of boost just fine imo, for short bursts.
The goal is realistic.
High rpm or sustained rpm over 5000 is usually what breaks cranks. |
|
| Back to top |
|
|
Dan Ruddock
Samba Member
Joined: October 25, 2012
Posts: 3594
Location: Sarasota, in my adopted state of Florida
|
| Posted: Fri Mar 29, 2024 10:37 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
| modok is correct, the other factor is quality control. How consistent are China parts? IMO not as good as a German core crank modded into a stroker crank. |
|
| Back to top |
|
|
woodsbuggy
Samba Member
Joined: December 15, 2007
Posts: 210
Location: NE Indiana
|
| Posted: Fri Mar 29, 2024 9:10 pm Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
Thanks for the input, the crank that I plan to use is Chevy journal, I will have everything balanced after 1st assembly. I understand that DPR and others build very nice stroker cranks but feel that a welded stroker crank looses core strength as the stroke increases. Also is cyro treating cylinders a worthwhile procedure for a turbo motor? Thanks Again for taking the time to share your experience and knowledge.
Kenric
_________________
The empty can rattles the most! |
|
| Back to top |
|
|
vwracerdave
Samba Member
Joined: November 11, 2004
Posts: 15313
Location: Deep in the 405
|
| Posted: Fri Mar 29, 2024 9:22 pm Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
With 275 HP another thing you need to worry about is the flywheel sheering the dowel pins off the crank. You need to consider wedge mating the crank & flywheel or getting a flanged crank.
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK |
|
| Back to top |
|
|
Ohio Tom
Samba Member
Joined: February 09, 2006
Posts: 1660
Location: Marshallville Ohio
|
| Posted: Sat Mar 30, 2024 7:56 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
| you will twist the 8 dowels off regardless. Should be at least wedgemated. Or, better option is to step up to a Flanged crank. They are significantly better quality. |
|
| Back to top |
|
|
mcmscott
Samba Member
Joined: March 12, 2010
Posts: 4858
Location: sanger ca
|
| Posted: Sat Mar 30, 2024 9:26 am Post subject: Re: Will a China crankshaft handle 275HP and 275ft/lbs? |
|
|
As I agree a flanged or wedgemate is better, I have been using standard 8 dowell in a 2300 lb car on slicks running mid 1.50 60 ft times for over 4 years, motor makes close to 350 hp. No clutch management, just standard stage 3 and a repadded 6 puck.
_________________
There are no stupid questions, only stupid people,
68 Ghia
67 T-1
65 Notch
02 Mexican beetle
74 Thing
15 Long travel rail
07 Nomad
05 f-250 |
|
| Back to top |
|
|
|
