John Mihovetz [ ACCUFAB ] Modifying my crankshaft


Lorenzo

GT Owner
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626
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Sinovac, Thank you for the new information, I appreciate it. The reason i originally searched for and found this forum was to converse with other owners and gain knowledge regarding the car.
Thank you.
 

Fubar

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Don't regret starting the thread. I love a good debate when people know what they are talking about.

+1 I have been very interested in the subject matter discussed here.
 
H

HHGT

Guest
This is an owner's only thread, isn't it?
 

2112

Blue/white 06'
Mark II Lifetime
Just a note of clarification on swapping Dampers.

If your engine (any engine) is internally balanced correctly, you can swap dampers as long as you stay with a non-weighted, internally balanced style damper......If you have the room to do it.

It has been suggested that you have to re-engineer your engine build to swap them. Not true.

Has anyone swapped the damper with the motor in the car? That is the $$ question.
 
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BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Has anyone swapped the damper with the motor in the car? That is the $$ question.

I have read somewhere that it has been done. That said I also have heard of cases where the crank bolt is extremely tight and VERY difficult to remove. There isn't clearance for a impact wrench, so a long breaker bar would have to be used if the engine is in place. If that torque to yield bolt snaps, be prepare to pull the engine!

This is Shadowman's play by play on the bolt removal with the engine out of the car.

"...Now during this process the only difficult encountered was the removing of the harmonic balancer crank bolt; it took time …. heat .… time …. heat …. time …. heat …. and an impact driver and nearly an hour later it finally broke loose. Once the bolt was out the harmonic balancer with the assistance of the OEM puller came off very easy."

If Shadowman has problems, I wouldn't dare try to touch that bolt without thinking I have a 50/50 chance I will have to pull the motor!

Also do a search on www.modularford forum, others have had issues with the crank bolt too.
 

Waldo

GT Owner
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Sep 7, 2005
767
Fort Worth, TX
Ford uses this damper on the Cobra Jets.
It is also my understanding that Ford uses two keyways on the Cobra Jets.

...I think the contraversy here is that there has only been ONE crank failure and it was on a heavily moded engine and who knows mabie that crank had an underlying issue and would have failed regardless.
I would be very interested to hear from owners who have driven 5-10,000 miles since the installation of their Whipples. This may be an issue that could go undetected until the stock damper is removed or a crankshaft suffers a catastrophic failure. Lorenzo's damaged keyway could be the solitary data point for the simple fact that no other Whipple owners have removed their dampers to inspect the keyway. If any other owners have had similar damage, I hope they would post the details.

However, In hind sight i wish i would have never started this thread.
As a Whipple owner, I'm glad you did start this thread. It has generated some informative discussions to say the least.

Merry Christmas,
Waldo
 
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BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Removing your engine to modify your crank because it may fail with a Whipple is like removing your prostate because you will get eventually get prostate cancer. In both case the preventative measures cost big money and you forgo the pleasures of using your gifts.
 

Sinovac

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It is also my understanding that Ford uses two keyways on the Cobra Jets.
Perhaps on the latest Cobra Jet (2012). I don't believe the 2008 or 2010 have two keys. The CJ damper I bought has only one and I think it is a direct replacement part for the 2008/2010 Cobra Jet. However, there were 2 supercharged engines available for the 2010 Cobra Jet (Cobra Jet and Super Cobra Jet) so perhaps the higher output Super Cobra Jet had 2.
 
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Lorenzo

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Dec 28, 2008
626
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Removing your engine to modify your crank because it may fail with a Whipple is like removing your prostate because you will get eventually get prostate cancer. In both case the preventative measures cost big money and you forgo the pleasures of using your gifts.

Blackice this is the first time this thread has made me laugh.
 

Indy GT

Yea, I got one...too
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Jan 14, 2006
2,526
Greenwood, IN
Balancer


Thanks 2112, that is the thread which I referenced in my post. Good basic information on the balancer topic. And I recall, just like ICE, I believe Bill has replaced a stock damper while the engine was in the car, but it was a pain to accomplish.

Just a note of clarification on swapping Dampers.

If your engine (any engine) is internally balanced correctly, you can swap dampers as long as you stay with a non-weighted, internally balanced style damper......If you have the room to do it.

It has been suggested that you have to re-engineer your engine build to swap them. Not true.

Has anyone swapped the damper with the motor in the car? That is the $$ question.[/url]

Most, if not all, current engines to my knowledge are balanced internally. And thus the balancer itself has a uniform distribution of mass around the full 360 degrees of balancer circumference. The only engine of which I am aware that DID use an external balance through the harmonic balancer was the Chevy 400 cuibic inch small block engine. This engine was never viewed very favorably by the performance crowd due in part to its bore/stroke ratio but you HAD to use the external harmonic balancer specifically designed for this engine to correctly dampen crankshaft harmonics.

Indy GT, Thanks for the reply. As always a welth of technical knowledge. I couldn't agree more that to pull a perfectly good running motor from one of these cars because someone is concerned about the keyway or balancer would be very silly. Mine on the other hand was already out for other reasons and the work i had preformed was done as an addition to my other modifications.[/url]

Lorenzo, Thanks and I completly agree. Your situation is completely different in that you had the engine out and parts on the table to message. And Bill and John are very accomplished at taking care of the mechanics of our FGT engines. My hope was to comfort other owners of even highly modified GT engines that this was a crankshaft modification which they really needed to accomplish sooner than later. The modification just does not need to be made in my opinion.

I understand that the 2007 GT500 damper is similar in design, and was based on, the Ford GT damper. Perhaps someone can post a picture of the Ford GT damper.[/url]

And finally Sinovac, why must you keep trying to compare Apples to Oranges? If you go back and read the reference history link you will understand the two dampers (GT500 vs. FGT) MAY be similar. Heck the harmonic damper on an old Chrysler slant 6 is similar too. They both attunuate unwanted crankshaft harmonics by turning the energy into heat. But again, please understand, the GT500 and FGT dampers are NOT the same and trying to compare the two only serves to confuse others. Thanks!
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Indy, Bill aka Shadowman removed the balancer with the engine out of the car, but mentioned that it was a big PITA. So much so that in his opinion, removing one in vitro would be risky without the understanding that the motor may need to be removed. This was Ed's car. Shadowman said the balancer and crank was in very good condition and it was so tight, that it was a non-issue for Ed's engine. This doesn't mean that all balancers are that tight and thus "safe" with a Whipples, but Ed's it was. Sample size of one is not proof of anything.

Bottom line, IMO, I am comfortable with the risks of running a Gen 1 Whipple, even at 21 PSI with a stock balancer and single keyway. But I always obey the laws of man and nature so I drive "like a little old lady." If I were to ever pull the engine for another reason I would inspect the crank if I had any doubts I would not hesitate to "upgrade" to dual keyways with a larger ARP bolt as John M recommends. If the crank had to be removed anyway, I would "upgrade" for sure.
 

Sinovac

GT Owner
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5,832
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And finally Sinovac, why must you keep trying to compare Apples to Oranges? If you go back and read the reference history link you will understand the two dampers (GT500 vs. FGT) MAY be similar. Heck the harmonic damper on an old Chrysler slant 6 is similar too. They both attunuate unwanted crankshaft harmonics by turning the energy into heat. But again, please understand, the GT500 and FGT dampers are NOT the same and trying to compare the two only serves to confuse others. Thanks!

I never said they were the same. If you read my prior post carefully you will see I was merely pointing out that Ford has recommended a lighter damper for the 2007 GT500 in higher boost applications to prevent crankshaft failure, and that a lighter damper on the GT might help alleviate any perceived concerns with the GT crank. I would be surprised if my posts confused anyone that read them carefully. I don't sell any parts or services. I was merely passing on information that might be helpful.
 

fjpikul

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IndyGT is apparently trying for a new word to be added to the dictionary before the year's end. Attunuate? Maybe attenuate?
 

B.M.F.

GT Owner
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Jan 29, 2009
1,785
Minnesota
[QUOTE=Indy GT;259822}


Most, if not all, current engines to my knowledge are balanced internally. And thus the balancer itself has a uniform distribution of mass around the full 360 degrees of balancer circumference. The only engine of which I am aware that DID use an external balance through the harmonic balancer was the Chevy 400 cuibic inch small block engine. This engine was never viewed very favorably by the performance crowd due in part to its bore/stroke ratio but you HAD to use the external harmonic balancer specifically designed for this engine to correctly dampen crankshaft harmonics.
__________________________________________________________________________________________

Most all FORD Pushrod motors until the mod motor in 1992-93 were externally balanced...289,302,351w 429/460/ 351 clevland 400m/ 360 chrysler/454 chevys, etc You worked for ford didn't you?

I have a 05-6 gt balencer and a 07 Gt500 balencer side by side here. Both motors 5.4, same stroke, both motors supercharged. The balencers are identical except the distance between the 6 rib and the 10 rib. .100 thats it... How can you not compare them? Did you design the balencer in the Gt? How are they different when both motors are internaly balenced and besides the dry sump mostly the same?

By 2008 ford redesigned the balencer on the gt500 and made it 10lbs lighter, HELP ME UNDER STAND WHY?. Then ford racing built the CJ mustangs and many people have been tearing the single key ways out of them with the big whipples 24lbs + of boost. So now they are double keying them from the factory. Ford Racing also tested with Ford's Balencer testing proceedures the Innovators west along with ati's balencers. They choose Innovators cause it was the best design, but they would not give Innovators West any of the info to as why. But it was better than stock and better than Ati's. Hense the reason ford is putting them on the brand new Cj mustang racecars. I have been told before on this balencer deal that Ford Racing is not doing the same testing ford does but i know that Ford is doing the testin for ford racing.

Anyways we all know the balencer is good for a stock car up to and over 1000hp with a turbo. There has only been a few cars that have made over 800rwhp with a whipple in a Gt. Just like anything else after a certain point stock is no longer good with some components and there are better things out there for the hp intended. I am sure that ford did not test this balencer @ 1400hp. Nor would i run @ that level for extended periods of time. But that is my preference and my opinion... I have raced many things over the years with centrifial blowers and 1'' of keyway on the balancer to crank contact for the amount of hp needed to turn these big blowers at big boost levels is NOT enough. I know this from real world experince...
 
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2112

Blue/white 06'
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IndyGT is apparently trying for a new word to be added to the dictionary before the year's end. Attunuate? Maybe attenuate?

Spelling bee champ by chance, Doctor? :biggrin
 

fjpikul

GT Owner
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No, Indy GT hater. Just kidding Bill 'ol buddy.
 

Fubar

Totally ****** Up
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IndyGT is apparently trying for a new word to be added to the dictionary before the year's end. Attunuate? Maybe attenuate?

Dr. Frank must be into his second or third glass by now as he is well aware that Bill does not respond well to being corrected. I'm going to get some popcorn, this should be good.
 

Sinovac

GT Owner
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This is a good, informative and civil discussion. Since its Christmas, think WWJD? I think He would put a lighter damper on His GT if He had the motor out for any reason :)
 
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Fubar

Totally ****** Up
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Please send any hate mail related to this video to fuguys@drfrank.com

[video=youtube;pe-er9FqhYA]http://www.youtube.com/watch?v=pe-er9FqhYA[/video]
 

Sinovac

GT Owner
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Thanks alot Fubar. That is a thread killer for sure. Besides, everyone knows He would prefer a Colt pistol and a S&W revolver.