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TOPIC: 5spd. Transaxle + 10lbs. Boost =

5spd. Transaxle + 10lbs. Boost = 17 Aug 2012 09:41 #10241


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Well I got the results of my transxale autopsy from Ken yesterday. This is the result of boost at Watkins Glenn. It could have been worse so I'm not complaining, but beware, if you want to go fast, you have to pay!

http://www.youtube.com/watch?v=cH85xLbhWas

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5spd. Transaxle + 10lbs. Boost = 17 Aug 2012 10:10 #10242


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ugh :eek:
Was this an '85 US transmission? Just curious.

Do you know, or suspect, the exact cause? I would conjecture that it is too quick of a change in torque with tires so wide they won't easily spin.
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5spd. Transaxle + 10lbs. Boost = 17 Aug 2012 14:31 #10250


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I know that would happen when drag racing and you get to much traction.
I cant remember if it was the T-10 trans or what but I think the fix was borg warner gears at about $300 each and that was 25 years ago.

Ummm isn't Mike working on a super strong trans?
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5spd. Transaxle + 10lbs. Boost = 17 Aug 2012 15:05 #10252


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Yes it is an 85 US box. I had no warning that this was about to happen. I had a great day before and this was 3 laps into the second day first run. I have to admit I was much faster that the previous day and past time there but realistically I think maybe the trans fluid wasn't rally up to temparature and the gears brittle. Not sure but I have been told that gobs of torque do that to parts.
Brad, I am lusting after Mike's Jerico trans idea and hope he really persues making more but I have a feeling he may not. I hope I am wrong and I think with enough poking we can convince him that this is a good idea. At least for track use.
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5spd. Transaxle + 10lbs. Boost = 17 Aug 2012 22:46 #10255


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I really hope that Mike makes them available. Obviously, there is a VERY limited market, but if it means you can crank the boost up in our manual 928s I am willing to buy one.

I'd love to be able to "powershift" a 928 without having to worry about a failure. I've been a gear banger for years, and I LOVE the T56 that I had in my Trans AM and my Corvette. The amount of punishment those transmissions can take is incredible.

Sorry about the failure Ed, but hey, maybe if enough get broken we'll HAVE to find/make something else that works! I think we're kinda there now though.
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5spd. Transaxle + 10lbs. Boost = 18 Aug 2012 00:28 #10256


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Hate seeing pics like that! Good luck Ed!
James
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5spd. Transaxle + 10lbs. Boost = 23 Aug 2012 17:55 #10494


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Heading back to Watkins Glen tomorrow with bigger brakes,bigger tires and better transmission. I'm having bad thoughts of a repeat but I am trying not to let that stop me.
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5spd. Transaxle + 10lbs. Boost = 23 Aug 2012 22:53 #10514


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Its really to bad that we dont have a drop in performance trans Like you could behind any of your big blocks. You would wet yourself with a super T-10 in that baby

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5spd. Transaxle + 10lbs. Boost = 23 Aug 2012 22:55 #10515


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What transmission Ed? You'll have to let us know what happens. Hopefully your day won't be cut short by another failure.

You could always just run REALLY skinny tires, and then worry about tire degradation instead of braking transmissions!
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5spd. Transaxle + 10lbs. Boost = 23 Aug 2012 23:04 #10516


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Jon B.;10843 wrote:
What transmission Ed? You'll have to let us know what happens. Hopefully your day won't be cut short by another failure.

You could always just run REALLY skinny tires, and then worry about tire degradation instead of braking transmissions!

ROTFLMAO oh my god now that is funny
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5spd. Transaxle + 10lbs. Boost = 23 Aug 2012 23:06 #10519


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Jon B.;10843 wrote:
You could always just run REALLY skinny tires, and then worry about tire degradation instead of braking transmissions!

YESSSS! Good answer!
James
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5spd. Transaxle + 10lbs. Boost = 24 Aug 2012 08:15 #10525


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Jon B.;10843 wrote:
What transmission Ed? You'll have to let us know what happens. Hopefully your day won't be cut short by another failure.

You could always just run REALLY skinny tires, and then worry about tire degradation instead of braking transmissions!

NO WAY! Once you go fat, you never go back!:eek:

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5spd. Transaxle + 10lbs. Boost = 24 Aug 2012 08:55 #10528


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Somewhere, in every chain, there will be a weakest link. That includes the chain from the right foot to the ground...
Wally Plumley
928 Specialists
www.928gt.com
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5spd. Transaxle + 10lbs. Boost = 27 Aug 2012 11:42 #10655


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Back from Watkins Glen and the replacement transmission held together with no issues! And the big stickies worked so well I pushed the envelope so much further than I ever have and it stuck like glue. i guess I need more boost!:eek:
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5spd. Transaxle + 10lbs. Boost = 27 Aug 2012 20:56 #10693


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^^^^^^
LOL! Yea, that is what I was thinking MORE BOOST! You will just find the next weakest link in the chain if you keep doing that Ed! LOL!
James
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5spd. Transaxle + 10lbs. Boost = 28 Aug 2012 22:35 #10743


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OBehave;10990 wrote:
Back from Watkins Glen and the replacement transmission held together with no issues! And the big stickies worked so well I pushed the envelope so much further than I ever have and it stuck like glue. i guess I need more boost!:eek:

Wow that was quick. I see you need some vented rotors on there.
Glad the tires and trans held up.
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