John Mihovetz [ ACCUFAB ] Modifying my crankshaft


H

HHGT

Guest
I would like to send him something more personal, do you have a mailing address?
 

Indy GT

Yea, I got one...too
Mark IV Lifetime
Jan 14, 2006
2,388
Greenwood, IN
More Balancer....

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.
ICE – Thanks for the clarification. Too many things to try to remember. I just remember removal of the balancer insitu has been previously discussed and it is very difficult to do.

Attunuate? Maybe attenuate?
Thanks Frank for spellchecking (and even reading) my post. Good to know you have my back….. I usually have a dictionary close by and use it frequently. This one just got by in the flurry of composition. Would be nice if the Forum had a spell check feature; but I think you got the gist of what I was trying to say. And I hope this post goes to prove your point on my verbosity (I looked it up first).

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.
Sinovac – Perhaps you did not use the word phrase “they were the same”, however the numerous posts discussing the differences between the FGT balancer and the GT500 units together with the comparative pictures supports your underlying question, “Why did Ford use a different harmonic balancer on the FGT than on the GT500?” I really do not mean to be dismissive here, but why do you CARE? Because one crankshaft out of 4,038 broke for some unknown reason and all us owners should be concerned?

Sure, the Ford 5.4 balancers are “similar” in that they absorb unwanted crank-train harmonics and convert this into heat to be dissipated. All harmonic dampers provide the same function. But the MOD5.4 engines in our FGT are DIFFERENT than the MOD5.4’s in the various flavors of the GT500, Cobra Jets and/or truck applications. So why would one expect all these engines would have identical harmonic dampers? It is unclear how you establish linkage between what Ford is recommending for the iron block MOD 5.4 in the ’07 GT500 (“…Ford has recommended a lighter damper for the 2007 GT500 in higher boost applications to prevent crankshaft failure,”) to the rotating bottom-end components we have in our FGT engine (“…and that a lighter damper on the GT might help alleviate any perceived concerns with the GT crank.”). Ford (or Ford Racing Products (?)) is making the recommendation for a different engine, NOT the engine in the FGT.

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?
Sorry B.M.F., I have never worked for any of the automotive companies. Not sure where that one came from…? But thanks for sharing. I grew up on Chevy small blocks so that might be a true statement.

By 2008 ford redesigned the balencer on the gt500 and made it 10lbs lighter, HELP ME UNDER STAND WHY?
How would I know?? (other than to restate the obvious fact that the engines are all different) Write a letter to the Ford Engineering department and ask them! I am sure all the car companies have proprietary design software calibrated with field experience to design and analyze drivetrain harmonics. I do know, factually, from talking to engineers and managers on the design team for OUR application specific engine that an extensive amount of costly testing and verification work was undertaken before final engine release. Recall in Petunia’s formative stage several different engine powerplants were proposed and once Bill gave the green light for the concept to proceed to production, the MOD V8 proponents (as well as FMC) wanted to make absolutely sure the engine would perform its intended function without any hiccups. (which it has, and is a tribute to the team)

B.M.F., here are just a few design considerations that come to mind when asked why dampers “might” be different between two “similar” MOD5.4 engines: engine firing order, design BMEP, block material, block main bearing webbing, main bearing cap design and material, main bearing bolt material and preload, crankshaft geometry, counterweight design, crankshaft material and processing, main bearing design and running clearances, rod bearing design, material and running clearances, rod bolt material, connecting rod material, piston material, ring configuration, material and running clearance, wrist pin offset, flywheel geometry and flywheel attachment bolts. Although there may be others (I do not profess to know all the variables) and some of the above are likely more primary influencers than others, it is reasonable to assume that Ford engineers just “may” have changed one or several of these variables in tweaking the various MOD5.4 offerings they install in the Mustang. Write and ask them.

For those so inclined, a wealth of technical information as to the design and development of our FGT engine, drivetrain and aerodynamics, can be gleaned by reading the eleven published technical articles in SAE publication PT-113, “The Ford GT: New Vehicle Engineering and Technical History of the GT-40”.

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.
Mark, how’s the popcorn, buddy? Incidentally you comment on declutching the supercharger during shifting could be accomplished with a device called an “overriding clutch”. It is frequently used in multiengined helicopters to take a failed engine off-line and not steal power from the good engine to rotate the failed engine. In electrical terms think of an overriding clutch as a diode which only permits torque to travel in one direction. Might make an interesting application.
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,507
Largo, Florida
Sinovac – Perhaps you did not use the word phrase “they were the same”, however the numerous posts discussing the differences between the FGT balancer and the GT500 units together with the comparative pictures supports your underlying question, “Why did Ford use a different harmonic balancer on the FGT than on the GT500?” I really do not mean to be dismissive here, but why do you CARE? Because one crankshaft out of 4,038 broke for some unknown reason and all us owners should be concerned?
Indy, I care much less about the issue than you obviously do. You have missed the entire point of my posts. I have not suggested, nor do I believe, that all GT owners should be concerned about the damper . In fact, my posts clearly indicate otherwise. My point was simply this-IF someone is concerned about the issue, I see no reason why a lighter damper won't minimize any perceived risk of failure. IF a GT owner already has the motor out, why not install a lighter damper in light of the issues with the VERY similar 2007 GT500 damper. I'm not suggesting that any owner ought to pull the motor to change the damper, but if I'm working on the car to the extent Lorenzo is (you remember him, the original poster who was looking for information on the topic), I'm not going to leave the stock damper alone. To be more clear, I'll give you an example. Let's say someone has a bug up their a**, but that bug only has a 1% chance of causing any problems with his intrapersonal relationships. It would be foolish for that person to have a procedure just to remove the bug. However, IF that person is already under the knife and has a doctor up his a**, the good doctor just might say "why don't we remove that bug since I'm already here" thereby eliminating whatever risk, no matter how small.

I have cross examined enough expert witnesses in my career to know when someone is so clearly biased in their opinion that they refuse to consider any other information.
 
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BlackICE

GT Owner
Nov 2, 2005
1,412
SF Bay Area in California
...My point was simply this-IF someone is concerned about the issue, I see no reason why a lighter damper won't minimize any perceived risk of failure...
Perceived risk may not by real risk.

But more importantly I there may be enough differences between a GT500 engine and a FGT engine to the extent that the optimal balancer design between the two would be different. Only Ford and or their engineering partners know for sure. The GT500 market is large enough to support the proper design and testing of a alternate balancer. Whether or not proper testing was done, I don't know. In spite of that, sample size of modified GT500 with different balancers is much larger by 100X, or more compare to a FGT. So the guinea pigs may be end users. Since I haven't heard of any problems with the after market GT500 balancers it appears they are no worse or better than an OEM for a modified engine. But who wants to be the guinea pig with there FGT? What do you think the number of FGT using non-OEM balancers are? Given we know of only one failed crank (not due to a bigger blower), why all the fuss?

I believe there an owner in NZ is running a Whippled FGT with a stock balancer in a number 24HR endurance races. If he hasn't seen a problem, I doubt I ever will!
 
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Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,507
Largo, Florida
Perceived risk may not by real risk.
Exactly. That is why I used the word "perceived".
 

Indy GT

Yea, I got one...too
Mark IV Lifetime
Jan 14, 2006
2,388
Greenwood, IN
I have cross examined enough expert witnesses in my career to know when someone is so clearly biased in their opinion that they refuse to consider any other information.
The facts speak for themselves. (That's why they are called "expert" witnesses, but please let's not jump to that topic...)

Interestingly, I have had the pleasure of guiding many attorneys regarding technical issues on their cases. They freely admit to knowing nothing about the physical mechanics necessary for them to try their case. I deduce, however, you posess an engineering degree as well and have the topic figured out.

Ok, counsler, I concede.

Do what you want, however misguided.
Perhaps I will get a chance to meet you in a deposition some day....

Mark, put the popcorn away.
 
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GT35065

GT Owner
Mark II Lifetime
:pop:beer2: Sorry, coundn't help myself. Cold and windy, not much else going on here at the moment.
 

Ed Sims

GT Owner
Mark IV Lifetime
Apr 7, 2006
7,095
NorCal
Shadowman had Al Papito work on my crank & he had John at Accufab do the cams & head work. I have 21,000 miles on the DA modded engine with no problems. Runs smoother than stock! Flows air like crazy!

Ed
 

fjpikul

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Jan 4, 2006
10,064
Belleville, IL
Sinovac, a better analogy would be taking out the appendix. Most abdominal and pelvic surgeries include removing the appendix (perfectly good) to prevent an additional surgery sometime in the future.
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,507
Largo, Florida
Indy, I'll let you have the last word with the "misguided" reference. You are a good sport.
 

Indy GT

Yea, I got one...too
Mark IV Lifetime
Jan 14, 2006
2,388
Greenwood, IN
As are you Sinovac!

We are both fortunate to own one of these wonderful cars and be Lifetime Members of an equally wonderful Forum to exchange our ideas.

Look forward to seeing and talking further at our next rally in Utah!
 

Accufab

Well-known member
Mar 14, 2006
142
Its kinda funny how there are so many opinions about this subject from so many that have never seen the internals of this engine. I know of a couple failures already and have fixed a couple. Not everyone posts their failures on this or any message board just so you know. Some poeple actually have more important things to do.

I am always up for a spirited discussion as long as I am dealing on an equal level with equally qualified individuals on the specific topic. In this case unless I'm mistaken, that person has not spoken yet. While I cannot predict the future, I can inform you of what the parts in front of me are telling me. I posted about this because I felt it would be useful information. And yes 95% of those here will never be affected by this problem.

In my case, I probably wouldn't tell anyone on here how to be a lawyer or how to fly a plane. That's not what I do and I just appreciate that they are experts at what they do if I ever need their services. But this particular field, this is what I do and I have certainly set the bar at every level thus far. For the few that are affected by this, I have a solution, not that I need the extra work.

I have built probably 25 GT based high performance engines and hundreds of 4.6 modular engines including Rays 2000 hp beast and my own 2300 hp beast. Probably devote 60 hours a week for the past 15 years to modular engine development. If I wanted the message diluted, I would do it myself.

All the best

John Mihovetz
 
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Accufab

Well-known member
Mar 14, 2006
142
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,507
Largo, Florida
John,

Your points are all well taken. The proof is in the pudding-you'll be building my next 1000hp GT500 engine.

Regards,

Paul
 

Heffner Performance

*Supporting Vendor*
Supporting Vendor
Feb 22, 2006
366
I know that this is a bit off topic but I have noticed a few people wondering about the possibility of removing the factory balancer with the engine in the car. I have removed at least a half dozen Ford GT balancers with the engine in the car and have never had any trouble whatsoever. I just used a standard harmonic balancer remover from Snap On and there is plenty of room for both the tool and a ratchet to tighten down the bolts. This can be done with ease by any qualified technician with the proper tools.
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,260
Minnesota
Well said John.... Also I have a balencer from Innovators West that they moddified for me so i didn't have to pull apart the motor to add a second keyway. They predrill the balencer and supply a hub and drillbit to add another key (I.E Roll pin to the crank) @ 180 degrees of the factory keyway. We do this all the time in Ls1 motors as you have to put 2 key ways in those as they have none. I have seen 25-30lbs of boost on a ls1 crank with no failure of the roll pins and I will be trying it with a gt crank with 35lbs of boost. Untill i get my billet cranked motor together:)

It would be possible todo this in a car with out pulling the motor out as you only need to drill 1''. It would probably be easier to pull the motor out though.
 
H

HHGT

Guest
Thanks again John for your input, it is always appreciated. I know I asked this before, but I will rephrase.

1) Will an occasional spirited drive on a Gen I or Gen II Whipple with 19 Lbs boost be a detriment or in your professional opinion what is the risk factor?
2) What will the Ford Pulley upgrade on a stock engine that's putting down 600+ HP, yielding 700+HP do to the Balancer?

Thanks in advance.
 

Accufab

Well-known member
Mar 14, 2006
142
I was hoping to avoid this subject but... I simply would not use any other balancer than ATI. If you can afford a $160,000 car, you can afford a good balancer. As for drilling the crank and using a roll pin, due to the limited space and the inherent half ass idea of that, I would prefer the proper route as the pin does not address the cam drive gear. The close quarters in the engine bay will not give much line of sight in order to help keep the drill straight.

The interference fit on every car is a little different. I cannot recommend using the 3.4 or 4.0 blower and predict how long it will last because everyone drives different and everyone stretches the truth about how they drive.

BTW I have a 1400 hp Shelby engine going in my Pro Street Mustang just for match racing laughs. Same engine that is in Rays car, just supercharged. We are going to beat it to death and see what happens to it.

John
 

BlackICE

GT Owner
Nov 2, 2005
1,412
SF Bay Area in California
The interference fit on every car is a little different. I cannot recommend using the 3.4 or 4.0 blower and predict how long it will last because everyone drives different and everyone stretches the truth about how they drive.

John
Thanks you John for your insights and wisdom on the topic. I don't doubt anything you wrote. However there are some that even 4.0 Whipple at 30 lbs would be OK for, EP comes to mind. I will get a chance to see and hear your fine work soon when Lorenzo's car come by my area. I heard Shadowman has the engine you built in place now.
 

Lorenzo

GT Owner
Mark II Lifetime
Dec 28, 2008
625
U.S.A.
blackice, it's closer then you think.


 
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