blew the powerdine up today.

[SASHO91]

My shaft doesn't flex, it just whines a little.

Sounds like a personal problem to me......



On a serious note, how much louder is that high dollar piece of metal you have.? Are you running any type of trans mount reonforcement?

 

[LJRuddy]

hmmm I see a battle of Mochas brewing!

mochas brewing!! :laugh_ti: :type:

 

[Mike Kopstain]

My shaft doesn't flex, it just whines a little.

I love that noise.

And that brings me to my point... The shot peening isn't addressing the issue. It's only bandaiding it. It's like having a poorly engineered building wood frame building collapse and instead of fixing the engineering problem you just build it with steel. You didn't address the underlying problem; you just bought some time until it re-appears.

There is no "solution" I would buy that didn't fix the issue with the shaft flexing. As long as that's happening the problem will repeat; it's just a matter of time.

Man, why do I always feel like the voice of doom?

 

[TYSHO]

So, who had the camera installed inside the transmission to determine the shafts flex? What's next, crankshafts flexing?


Edit:

If shot peening can keep a transmission together that's putting over 500whp for over a year with hard driving everyday, it should be more than enough to keep other boosted SHO's happy and worry free since there's not many running around with 500+whp.

I think the problem also [if indeed there was a camera installed to determine shaft flexing] lies in the DD pressure plate putting the power to the transmission gears instantly when upshifting in racing conditions. The teeth on those gears take a lot of stress with those upshifts and a DD pressure plate that doesn't allow for little slippage to absorb some of the power transfer.

 

[Lupo]

Sounds like a personal problem to me......



On a serious note, how much louder is that high dollar piece of metal you have.? Are you running any type of trans mount reonforcement?

Not really bad at all. You only really notice it while coasting in gear.
Stock trans mount. I really don't think you would need a different trans mount unless your engine mounts weren't doing their job.

 

[SHOMurph]

So, who had the camera installed inside the transmission to determine the shafts flex? What's next, crankshafts flexing?


Edit:

If shot peening can keep a transmission together that's putting over 500whp for over a year with hard driving everyday, it should be more than enough to keep other boosted SHO's happy and worry free since there's not many running around with 500+whp.

I think the problem also [if indeed there was a camera installed to determine shaft flexing] lies in the DD pressure plate putting the power to the transmission gears instantly when upshifting in racing conditions. The teeth on those gears take a lot of stress with those upshifts and a DD pressure plate that doesn't allow for little slippage to absorb some of the power transfer.

I agree with Brian on this one. No one knows if the shaft really flexes or not. It may be one of those long time SHO "theories."

The teeth on 2-4th are shallow and thin. I think that is the weak point over shaft flex. Shot peening so far has harded them up.

We'll see the lifespan on shotpeening.

 

[Yamaha V6]

I think the problem also [if indeed there was a camera installed to determine shaft flexing] lies in the DD pressure plate putting the power to the transmission gears instantly when upshifting in racing conditions. The teeth on those gears take a lot of stress with those upshifts and a DD pressure plate that doesn't allow for little slippage to absorb some of the power transfer.

I disagree Brian. Here's a video of my track car at NHIS, during the warm-up lap even - not getting on it, not trying to keep up with the Bimmer in front of me, etc. After completing the shift into 3rd the gear let go, and I wasn't even pushing.

http://www.sinclairmfg.com/fred/fred_trans.mpg

 

[Toolman]

I love that noise.

And that brings me to my point... The shot peening isn't addressing the issue. It's only bandaiding it. It's like having a poorly engineered building wood frame building collapse and instead of fixing the engineering problem you just build it with steel. You didn't address the underlying problem; you just bought some time until it re-appears.

There is no "solution" I would buy that didn't fix the issue with the shaft flexing. As long as that's happening the problem will repeat; it's just a matter of time.

Man, why do I always feel like the voice of doom?

I don't think we can say for sure that shot-peening does not address the issue, since the REAL ISSUE is gears breaking. In reality, the shaft could flex all it wants, but as long as the gears do not break, all is good. So, if shot-peening keeps gears from breaking, it address the REAL ISSUE. Same with your steel house. The choice of material certainly falls under the umbrella of 'engineering design'. To identical designs, but with wildly different materials (such as your wood/steel building), will have much different outcomes. A wooden bat does its job great. If it were made of concrete, baseball would never have become America's pastime.

So, to that end, if Tony's trans continues to perform without breaking (and keep in mind he is making a good deal more hp and a lot more TQ than Josh), I would say that shotpeening is where it's at (I still think it will break soon enough). Even if and when it does break, if it last 25k miles instead of 10k miles, then it still is much more cost effective than the 6k gearset, seeing as you can purchase a trans and shotpeen it for less than $300. 20 trans times 25k miles equals more miles than any SHO will ever get driven. That said, if I had the money in my left pocket, I would buy the HD gearset tomorrow. But the reality of life (and bills, and mortgages, and rent, and insurance, etc etc etc) is that $6000 is simply more money than I am willing to spend on a gearset if my $100 worth of shotpeening improves the life expectancy of my trans.

 

[Toolman]

I disagree Brian. Here's a video of my track car at NHIS, during the warm-up lap even - not getting on it, not trying to keep up with the Bimmer in front of me, etc. After completing the shift into 3rd the gear let go, and I wasn't even pushing.

http://www.sinclairmfg.com/fred/fred_trans.mpg

Perhaps, but how many times had you shifted in 3rd gear before that failure? Tony is making what, almost 500ft lbs? I think shotpeening deserves a second look.

 

[TYSHO]

I disagree Brian. Here's a video of my track car at NHIS, during the warm-up lap even - not getting on it, not trying to keep up with the Bimmer in front of me, etc. After completing the shift into 3rd the gear let go, and I wasn't even pushing.

http://www.sinclairmfg.com/fred/fred_trans.mpg

Okay, this video is another good point. You receive a lot of stress on the upshifts when racing, but there sure is an instant jolt to the gears on any upshift. As soon as you released the clutch, the gear gave up. At the time of giving up, is the time the gears received instant transfer without the help of the clutch absorbing any power transfer. Furthermore, you didn't give it any gas, so the pressure was reverse applied to the gear teeth...imagine it's like a paper clip and you wiggle it back and forth until it snaps in half. Over time, and after tons of shifts, the gears fatigue has about had it and will let go.


Is shot peening the cure? I don't know, but it has improved the fatigue of the gears significantly compared to stock and cyro'd gears. If you want an even better cure that will last a long time, have it laser peened. Do a search and check out the increase of fatigue and what not that's the result from the peening.

 

[TYSHO]

So, to that end, if Tony's trans continues to perform without breaking (and keep in mind he is making a good deal more hp and a lot more TQ than Josh), I would say that shotpeening is where it's at (I still think it will break soon enough). Even if and when it does break, if it last 25k miles instead of 10k miles, then it still is much more cost effective than the 6k gearset, seeing as you can purchase a trans and shotpeen it for less than $300. 20 trans times 25k miles equals more miles than any SHO will ever get driven. That said, if I had the money in my left pocket, I would buy the HD gearset tomorrow. But the reality of life (and bills, and mortgages, and rent, and insurance, etc etc etc) is that $6000 is simply more money than I am willing to spend on a gearset if my $100 worth of shotpeening improves the life expectancy of my trans.

Have those gears even been installed in a car with as much power as Tony is putting down? I'd actually like to see if those gears would hold up in a SHO with more power that's a daily driver.

 

[Mike Kopstain]

So, who had the camera installed inside the transmission to determine the shafts flex? What's next, crankshafts flexing?

Laugh all you want but our local mad scientist Josh Teixiera figured it out and quite frankly I would put more trust in what Josh says as a single person than a lot of things I see on this forum assumed as a collective whole.

since the REAL ISSUE is gears breaking

I guess it's a chicken or the egg argument but from an engineering standpoint I think anyone would deduct that the underlying problem is the shaft and not the gear itself though the shaft is exposing the weakness of the gear.

I don't believe shot peening is the answer and I don't buy into the mantra of replacing transmissions every 25k assuming you get that much out of them. Remember, you're also paying for your time to install, disassembling the unit, replac any potentially bad parts, and then for the shot peening itself. I'd muster up my nickels and dimes, sell my kids into slavery, and get the gearset.

 

[SHOMurph]

Laugh all you want but our local mad scientist Josh Teixiera figured it out and quite frankly I would put more trust in what Josh says as a single person than a lot of things I see on this forum assumed as a collective whole.


I guess it's a chicken or the egg argument but from an engineering standpoint I think anyone would deduct that the underlying problem is the shaft and not the gear itself though the shaft is exposing the weakness of the gear.

I don't believe shot peening is the answer and I don't buy into the mantra of replacing transmissions every 25k assuming you get that much out of them. Remember, you're also paying for your time to install, disassembling the unit, replac any potentially bad parts, and then for the shot peening itself. I'd muster up my nickels and dimes, sell my kids into slavery, and get the gearset.

awww screw it. I'm buying meez a GM product. I'm tired of all this shifting anyway!!

just kidding......

changing a tranny every couple of years really isn't that bad. I would love to have Josh's gearset but like Tim its hard to drop $6k at one time again for a play toy.....especially when I have extra trannys. We'll see how long the shot peening tranny last and go from there.

 

[Toolman]

I guess it's a chicken or the egg argument but from an engineering standpoint I think anyone would deduct that the underlying problem is the shaft and not the gear itself though the shaft is exposing the weakness of the gear.

Certainly, I am not arguing that the stock shaft sees no flex. The HD shafts flex some as well, just not as much. But plenty of other components in this world that use gears and shafts withstand, and are DESIGNED with a certain amount of flex in mind, yet they do not fail every 2 months. SOOOO, if shotpeening the gears allows them to withstand the stressors from a flexing shaft, even if it is not the FINAL solution, then why would anyone not want to shotpeen their gears? You can almost buy an ENTIRE S/C'd SHO for the price of the HD gearset! I can surely buy the parts for a SCREAMIN monster of a turbo system for $6000. And I can also buy AT LEAST 15 transmissions, and have the gears shot peened, for that same amount of money. My gears have been lasting about 15k miles each, before the shot peening. And my car produces a brutal TQ curve, much more than most SC'd cars will ever see. Even if I have to figure in my labor in changing out my trannies, I would still be money ahead after changing those 15 shot peened trans. Even if shot peening only doubles the life expectancy, my SHO would be a pile of rust LONG before I changed out 6-7 trannies.

THAT SAID, when I have the funds, I will quickly apply them to Josh's HD gearset, as my future car will be making my old HP/TQ numbers look very sedate. I agree with you that shot-peening is only a bandaid, but until I need (and can afford) major surgery, I want that band-aid.

I don't believe shot peening is the answer and I don't buy into the mantra of replacing transmissions every 25k assuming you get that much out of them. Remember, you're also paying for your time to install, disassembling the unit, replac any potentially bad parts, and then for the shot peening itself. I'd muster up my nickels and dimes, sell my kids into slavery, and get the gearset.

You can almost buy an ENTIRE S/C'd SHO for the price of the HD gearset! I can surely buy the parts for a SCREAMIN monster of a turbo system for $6000. And I can also buy AT LEAST 15 transmissions, and have the gears shot peened, for that same amount of money. My gears have been lasting about 15k miles each, before the shot peening. And my car produces a brutal TQ curve, much more than most SC'd cars will ever see. Even if I have to figure in my labor in changing out my trannies, I would still be money ahead after changing those 15 shot peened trans. Even if shot peening only doubles the life expectancy, my SHO would be a pile of rust LONG before I changed out 6-7 trannies.

THAT SAID, when I have the funds, I will quickly apply them to Josh's HD gearset, as my future car will be making my old HP/TQ numbers look very sedate. I agree with you that shot-peening is only a bandaid, but until I need (and can afford) major surgery, I want that band-aid.

I liken it to the issue of forged pistons. Do you HAVE to have forged pistons? Of course not, but many do. The stock pistons have been shown to be able to withstand a substantial amount of power, assuming you have the correct tune. Of course, forged pistons is the better option. And @ only $800 or so, they are worth it. But if they cost $6000, how many people would be putting forged pistons in their SHO's? Not me! If the HD gears were more in line with what higher volume parts cost, I would be all over them. As it stands, it is simply not feasible. I have a saving account geared specifically toward said purchase, but between my wedding/honeymoon bills, my mortgage, my rent, my insurance, my living expenses, etc, that account is growing slowly. Perhaps I can talk Lupo into selling my his car cheap!!!

 

[TYSHO]

Laugh all you want but our local mad scientist Josh Teixiera figured it out and quite frankly I would put more trust in what Josh says as a single person than a lot of things I see on this forum assumed as a collective whole.

Okay, if shafts are flexing, who all with a S/C'd SHO has the bearings and cups destroyed because of this? If none, the shaft doesn't flex. There's no way in **** those things can withstand the pressure that a shaft that is flexing can't. And then the gear teeth let go before the bearings and cups because of this shaft flex? I guess we need bearing gears? Someone should invent that!

Just because someone with one of the most respected SHO businesses and a powerful SHO makes the claim, doesn't mean he's correct because he's a highly respected member within the community. If he said the crankshaft and rods flex, are you going to believe that too? Sorry, but I don't buy the shaft flexing.

 

[SuperchargedSHOguy]

So...hows that powerdine coming along...

 

[Mr Anonymous]

Okay, if shafts are flexing, who all with a S/C'd SHO has the bearings and cups destroyed because of this? If none, the shaft doesn't flex. There's no way in **** those things can withstand the pressure that a shaft that is flexing can't. And then the gear teeth let go before the bearings and cups because of this shaft flex? I guess we need bearing gears? Someone should invent that!

Just because someone with one of the most respected SHO businesses and a powerful SHO makes the claim, doesn't mean he's correct because he's a highly respected member within the community. If he said the crankshaft and rods flex, are you going to believe that too? Sorry, but I don't buy the shaft flexing.

Josh is actually an engineer in real life. He's not just playing one on the internet as so many others do. Until someone with more impressive credentials says otherwise, I'll take his word for it.

 

[Toolman]

Being a proponent of shot-peening does not make one a disbeliever in the theory of input shaft flexing (or more precisely, twisting). It is certainly not indestructible. I for one have had my third gear break teeth with an entirely intact shaft. In fact, I do not think I have ever broken an input shaft. Am I an engineer? No, I am a realist. And realistically, I can not afford to spend $6000 on a gearset right now, especially if there is an alternative that seems at this point to be viable.

 

[TYSHO]

Okay, maybe I am confused as to what is flexing and in which way. I know it's the one piece input shaft with gears. Now what's flexing on it? I'm under the impression that the shaft in whole is turning from an "l" shape to a "C" shape. <--- Not that bad, but it gets the point across.

 

[texantony]

I agree with Brian M. I don't think the shaft if actually flexing or bending. We would have seen some sort of bearing wear or failure. I have broken 7 transmissions and have inspected all of them. Bearings and races were fine.

Now this is my opinion .
I think its the initial jolt of once you are in gear and release the clutch the gear is weak and can not take the pressure. All you need is a hair line crack to start the process.

I have the up most respect for Josh and alot of you here, but I mean no disrespect to anyone that thinks otherwise.