Crankshaft snout snapped

[ramirj2]

Is this the only crank Support solution available for us?
I contacted them but they can’t confirm compatibility with Whipple
Seems like a good insurance.

Sponsored

 

[ramirj2]

Proper installation...

+ 10 rib and 21 psi.

 

[Hayburner]

I just joined this forum because this thread has scared the sht out of me to be honest. I have my whipple ready to go on, stock dia ati, 10 rib kit, 3.5” pulley, 6 spd car that will be drag raced often. Now I’m literally having nightmares of my crank snout snapping Lol.
Would the kinetikmotorsports crank stud kit maybe be a saving grace?

 

[stang17]

Well, add another whipple , stock diameter ATI, MMR TG/OPG to the snapped crank list. Happened Friday night coming back home from a night racing at Numidia. I was in 6th gear cruising along around 2,000 rpm and all of a sudden it let go.

For those of you this has happened to, what dampener/balancer did you go with on your rebuild/new motor? Has anyone gone with crank support on their new setup?

It's frustrating as all hell as I spent the money on upgrading these parts to prevent something like this from happening. Motor has less than 13k miles on it and has had the whipple on it since day 1, installed at the dealer. The ATI dampener, TG, and OPG were dealer installed around the 7,000 mile mark after reading what happend to Shawn's motor with the failed OPG thinking it would be cheap insurance.

Car was making 780ish whp. I had just run my personal best time that night as well with a 10.73 at 131.75mph on a 1.61 60 ft 93 octane with Lucas oil octane booster 4120 race weight.

I'll be having Jensen Performance doing the new motor/rebuild. Hoping I can have something built to handle 800-900 whp for less than $10k. Initial over the phone quote for labor of removing and installing new engine was $1,000 to $1,500.

 

[turnswrench]

Well, add another whipple , stock diameter ATI, MMR TG/OPG to the snapped crank list. Happened Friday night coming back home from a night racing at Numidia. I was in 6th gear cruising along around 2,000 rpm and all of a sudden it let go.

Sorry to hear. Interesting that it failed despite dealer install. What crank bolt was used?

 

[stang17]

I had purchased the ATI balancer from Terry at Beefcake. An ARP crank bolt was included in my order.

 

[grabber_17]

Well, add another whipple , stock diameter ATI, MMR TG/OPG to the snapped crank list. Happened Friday night coming back home from a night racing at Numidia. I was in 6th gear cruising along around 2,000 rpm and all of a sudden it let

For those of you this has happened to, what dampener/balancer did you go with on your rebuild/new motor? Has anyone gone with crank support on their new setup?

It's frustrating as all hell as I spent the money on upgrading these parts to prevent something like this from happening. Motor has less than 13k miles on it and has had the whipple on it since day 1, installed at the dealer. The ATI dampener, TG, and OPG were dealer installed around the 7,000 mile mark after reading what happend to Shawn's motor with the failed OPG thinking it would be cheap insurance.

Car was making 780ish whp. I had just run my personal best time that night as well with a 10.73 at 131.75mph on a 1.61 60 ft 93 octane with Lucas oil octane booster 4120 race weight.

I'll be having Jensen Performance doing the new motor/rebuild. Hoping I can have something built to handle 800-900 whp for less than $10k. Initial over the phone quote for labor of removing and installing new engine was $1,000 to $1,500.

Sorry to hear that man. This topic gives me nightmare's.

 

[sigintel]

Please measure the thickness of your stock damper and the ATI.

My theory:
If the ATI is too thick, it focus substantially more stress from crank snout flex to occur at the inside radius where the crank shaft steps down to the snout diameter.
I am guessing you will find thats exactly where the crank broke.

If your TG cant float slight AFTER the damper is torqued, then you just made the snout WAY stiffer than stock and there will be a huge stress concentration at the step in crank diameter inboard of TG.

In machinist terms: I think you might want the crank damper registered on the end of the crank, and not compressing the timing gear.

 

[Notheryote]

Every snapped crank about I’ve seen has been an aftermarket balancer I think, or at least the majority of them.

Really makes me want to avoid going 10 rib...

 

[ramirj2]

Please measure the thickness of your stock damper and the ATI.

My theory:
If the ATI is too thick, it focus substantially more stress from crank snout flex to occur at the inside radius where the crank shaft steps down to the snout diameter.
I am guessing you will find thats exactly where the crank broke.

If your TG cant float slight AFTER the damper is torqued, then you just made the snout WAY stiffer than stock and there will be a huge stress concentration at the step in crank diameter inboard of TG.

In machinist terms: I think you might want the crank damper registered on the end of the crank, and not compressing the timing gear.

That is correct!
This is mine. Torqued properly but not seated al the way in.

 

[ramirj2]

Well, add another whipple , stock diameter ATI, MMR TG/OPG to the snapped crank list. Happened Friday night coming back home from a night racing at Numidia. I was in 6th gear cruising along around 2,000 rpm and all of a sudden it let go.

For those of you this has happened to, what dampener/balancer did you go with on your rebuild/new motor? Has anyone gone with crank support on their new setup?

It's frustrating as all hell as I spent the money on upgrading these parts to prevent something like this from happening. Motor has less than 13k miles on it and has had the whipple on it since day 1, installed at the dealer. The ATI dampener, TG, and OPG were dealer installed around the 7,000 mile mark after reading what happend to Shawn's motor with the failed OPG thinking it would be cheap insurance.

Car was making 780ish whp. I had just run my personal best time that night as well with a 10.73 at 131.75mph on a 1.61 60 ft 93 octane with Lucas oil octane booster 4120 race weight.

I'll be having Jensen Performance doing the new motor/rebuild. Hoping I can have something built to handle 800-900 whp for less than $10k. Initial over the phone quote for labor of removing and installing new engine was $1,000 to $1,500.

The only crank Support that I had found is the MFP and it is made for the TVS that runs in the AC side of the crank.
I think I will buy one of these and modify to run the accessory side like Whipple.

 

[Roh92cp]

This shit pisses me off. I lost my first motor OPG failure due to MMR (Romac) damper likely being the cause with stock OPG. Now I have this dam ATI on and worried I'm risking another engine failure. Got dam this crank bolt and snout snapping thread has been always been at the top of this forum and I can't seem to get away from it, gives me a sick felling when I see it really.

2 years ago I took out my ARP crank bolt and installed the MMR bolt with step down washer that supports the snout face and balancer together. Not sure if this has come top her before ( haven't read the entire thread) but her it is and live been using this since.

Maybe it's time to go back to the stock damper or the newer 18-20 dampers that have a better record. Anyone know if the newer 18-20 damper work on 15-17's?

here is the MMR bolt and washer I use.
http://www.modularmotorsportsracing.com/cart/index.php?main_page=product_info&products_id=1011

 

[grabber_17]

The only crank Support that I had found is the MFP and it is made for the TVS that runs in the AC side of the crank.
I think I will buy one of these and modify to run the accessory side like Whipple.

If memory serves me correctly, I don't think the factory balancer sits flush in the keyway. I remember cleaning a ton of the factory sealant from the inside of the balancer and the end of the keyway. Maybe I am wrong.

 

[grabber_17]

Sorry replied to the wrong post.

 

[Jay-rod427]

I measured mine on install, and the ATI hub was within .001" same thickness as the stock balancer.

Sponsored