Bracket Talk
How many runs on Crankshaft
February 21, 2020, 07:35 PM
Bigdrive88How many runs on Crankshaft
Just curious, I have a Callies Compstar 4.250 Crank in y 565 that has approx 1200 passes on it. Probably 1100 of those are 1/8 mile. Motor will be due for a freshen after this coming season. Was thinking about maybe going to a 4.375. Is there a # of passes on a crank when you guys would say thats enough & time to replace
February 21, 2020, 10:38 PM
"The Bender"It's time. Cheap insurance. Just think about the damage and expense a broken crank would cause.
272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'
2017 Bradenton Heads Up Madness
Open Outlaw Champ
2018 PDRA T/D #5
2019 PDRA T/D #2
2020 Retired From T/D Competition....
2020 Bradenton NMCA Hemi Shootout Winner
2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
February 22, 2020, 07:06 AM
green1I don’t know the number of runs but I ran my Callie’s Magnum 4.375 12 seasons without issues. This crank is still standard on rods and main journals but was never spun over 7200 rpms. If I had to guess I would say 1500 runs or more. It’s my spare motor now.
February 22, 2020, 09:43 AM
Rick!Has the crank ever suffered any trauma like a broken rear end or broken engine part and loss of oil pressure?
If so, it's time.
If not, what's the convertor stall and trap RPM?
You can estimate cycles using an average RPM between the two, multiply by run time of the lap and burnout and come up with a number. Making some guesses, your crank has under 750,000 cycles on it. My brother's crank had just under 750,000 cycles on it.
My brother's Callies Magnum went 820 laps before it failed but it experienced a broken pinion at the launch once and a broken rocker once at 820 feet and oil pressure went to zero. The kicker was that 27 laps before it broke, the engine guy "inspected" it for cracks and missed the one in the #4 main fillet.
If I was to put my brother's engine on a program, I'd be replacing cranks at 500,000 cycles which is around 560 laps or about every 3 years.
Sell your crank to some kid and buy some peace of mind.
YMMV.
February 22, 2020, 09:46 AM
Roger McGinnisTime to put it on racing junk as "dyno time only"!
ΜΟΛΩΝ ΛΑΒΕ
February 22, 2020, 09:54 AM
Mike RietowAccording to the number of runs provided, the crank has 170 miles on it at wide open throttle, including burnouts.
Call the manufacturer for their opinion. Mention 170 miles WFO
NASCAR crankshafts are sold at 800 miles. Who knows how many miles they see WFO after that.
February 22, 2020, 10:39 PM
Bigdrive88Right. That is in the back of my mind for sure
quote:
Originally posted by "The Bender":
It's time. Cheap insurance. Just think about the damage and expense a broken crank would cause.
February 22, 2020, 10:41 PM
Bigdrive88Never had an issue where oil pressure went to 0.Converter Stalls at 6800. Trap RPM 74-7500
quote:
Originally posted by Rick!:
Has the crank ever suffered any trauma like a broken rear end or broken engine part and loss of oil pressure?
If so, it's time.
If not, what's the convertor stall and trap RPM?
You can estimate cycles using an average RPM between the two, multiply by run time of the lap and burnout and come up with a number. Making some guesses, your crank has under 750,000 cycles on it. My brother's crank had just under 750,000 cycles on it.
My brother's Callies Magnum went 820 laps before it failed but it experienced a broken pinion at the launch once and a broken rocker once at 820 feet and oil pressure went to zero. The kicker was that 27 laps before it broke, the engine guy "inspected" it for cracks and missed the one in the #4 main fillet.
If I was to put my brother's engine on a program, I'd be replacing cranks at 500,000 cycles which is around 560 laps or about every 3 years.
Sell your crank to some kid and buy some peace of mind.
YMMV.
February 23, 2020, 07:10 AM
wideopen231I would call manufacture and if they say should not be problem I would have it checked while out. Then buy another and keep it for backup motor or sale it.
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February 23, 2020, 07:00 PM
imakehpWhy not mag the crank and then you don't have to wonder ?
.
Dave
F J B
February 24, 2020, 06:37 AM
Busted Knuckles^^^wet mag it for sure.
If it passes and you're not comfortable with it in your primary engine, use the crank and rods in a stroker with a factory block for a daily driver, street rod, etc. or sell it to a local that wants it for the same purpose.
Bottom line it this: If you cringe as the engine gets close to redline, replace it. If you can't/don't trust it, it'll always be in the back of your mind and will affect your racing.
Organized people are just too lazy to look for their $h!t.
February 24, 2020, 06:46 AM
MatrixAbsolutely change it. I had a compstar in my 572 with just over 1000 hits and it checked out fine but changed it just for piece of mind
February 24, 2020, 06:58 AM
Bigdrive88Cool. Thanks for all the opinions. I trust what I have but I also know there is nothing bulletproof. Will more than likely change it out after this season.
February 24, 2020, 07:49 AM
green1Just for the heck of the discussion, how many people know somebody who broke a new crank compared to how many broke and old crank?
I had a Trick Flow crank that cracked on a main journal and it started eating that bearing and I got it out before it broke. It was only three seasons old.
February 24, 2020, 08:31 AM
Big Stevequote:
Originally posted by green1:
Just for the heck of the discussion, how many people know somebody who broke a new crank compared to how many broke and old crank?
I had a Trick Flow crank that cracked on a main journal and it started eating that bearing and I got it out before it broke. It was only three seasons old.
Callies magnum, blown BBC 74 runs
February 24, 2020, 10:16 AM
BuckyAhh the two piece option. Man that ruins one's day.
Foxtrot Juliet Bravo
February 24, 2020, 11:01 AM
green1See the ones with 1000 runs prove they stay together.
February 24, 2020, 11:11 AM
Buckyquote:
Originally posted by green1:
See the ones with 1000 runs prove they stay together.
Don't they refer to that as "seasoned"?
Foxtrot Juliet Bravo
February 24, 2020, 11:29 AM
TD3550Looks like the rods "Didn't leave the area" either
Great save. How much you throwing in that beast?
40?
February 24, 2020, 12:17 PM
Big Stevequote:
Originally posted by TD3550:
Looks like the rods "Didn't leave the area" either
Great save. How much you throwing in that beast?
40?
30lbs boost, most likely pushing 2500hp on a 2000hp rated crank. It obviously developed a crack then broke. Engine locked up tight, rods stayed in, some minor damage to the #1 main. Did bend all my Ti ext valves which sucked.