928 Competition gearbox - alternative gearing ?
#1
Instructor
Thread Starter
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I have a rally prepared 928 - used for closed road stage rallying in UK / Ireland.
Great going weapon , but what it really needs is a close ratio gearbox and a sensible final drive ratio (sensible = top speed 125 mph (max 130 ??)
What options do I have - if any.
(Is it the only one in the world ???)
Great going weapon , but what it really needs is a close ratio gearbox and a sensible final drive ratio (sensible = top speed 125 mph (max 130 ??)
What options do I have - if any.
(Is it the only one in the world ???)
#2
Not the sharpest tool in the shed
Rennlist Member
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I have a rally prepared 928 - used for closed road stage rallying in UK / Ireland.
Great going weapon , but what it really needs is a close ratio gearbox and a sensible final drive ratio (sensible = top speed 125 mph (max 130 ??)
What options do I have - if any.
(Is it the only one in the world ???)
Great going weapon , but what it really needs is a close ratio gearbox and a sensible final drive ratio (sensible = top speed 125 mph (max 130 ??)
What options do I have - if any.
(Is it the only one in the world ???)
Sounds interesting.
#4
Nordschleife Master
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Changing the final drive doesn't give a "close ratio" gearbox. You'll be shifting more but you'll be using the same shift points. What you really want are gears that let you go between, say, 6200 RPMs and 5500 instead of 6200 and 5000. Changing the final drive just changes the road speed you shift at.
Unless you're in 1st gear there won't be an appreciable difference in performance. It could, conceivably, be worse if you've got to make extra shifts.
Unless you're in 1st gear there won't be an appreciable difference in performance. It could, conceivably, be worse if you've got to make extra shifts.
#6
Instructor
Thread Starter
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Glen L . Thanks for the tip ... that's why I wrote "close ratios AND final drive". now ... does anyone make anything , or has anyone had anything made AND hardened successfully ???
Yes UK based - Ireland to be precise
Now let's see if I can manage a photo
Yes UK based - Ireland to be precise
Now let's see if I can manage a photo
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#9
Nordschleife Master
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You're only real options is to get a different 928 gearbox and the ring-and-pinion for that. There are no aftermarket gear sets.
Once upon a time there were some 3.09 gears made but finding one would be a miracle. And like I was getting at, it won't help if you're not drag racing.
If you're breaking trannies then look into cryogenic treatment for the gears.
Last edited by GlenL; 04-27-2010 at 04:13 PM. Reason: 3.09? 3.06? Whats the difference?
#11
Rennlist Member
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And if you find one of those 3.09 rear ends and add it to a euro 2.75 box or GTS box, you basically get an S4 US 2.2 gear box, sans the 5th gear and gaining a "super 1st". ![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
I love the stories of those that installed them on the track and said how they were so much fun. I call that, " shift numerical identity fixaction" or "SNIF".
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I love the stories of those that installed them on the track and said how they were so much fun. I call that, " shift numerical identity fixaction" or "SNIF".
Sure. The answer is "no."
You're only real options is to get a different 928 gearbox and the ring-and-pinion for that. There are no aftermarket gear sets.
Once upon a time there were some 3.06 gears made but finding one would be a miracle. And like I was getting at, it won't help if you're not drag racing.
If you're breaking trannies then look into cryogenic treatment for the gears.
You're only real options is to get a different 928 gearbox and the ring-and-pinion for that. There are no aftermarket gear sets.
Once upon a time there were some 3.06 gears made but finding one would be a miracle. And like I was getting at, it won't help if you're not drag racing.
If you're breaking trannies then look into cryogenic treatment for the gears.
#14
Rennlist Member
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Jamie Houseman makes custom gearsets for anything. Not cheap but he's good. He's the one who made the 3.09 ring & pinions.
Houseman Automotive
6564 Decker Dr.
Lambeth, Ontario
NOL 1S6 Canada
phone: 519-652-3030
http://www.housemanautosport.com/
Regards, Hammer
Houseman Automotive
6564 Decker Dr.
Lambeth, Ontario
NOL 1S6 Canada
phone: 519-652-3030
http://www.housemanautosport.com/
Regards, Hammer
#15
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Met with Travis ( 954-445 6437 ) from the 944 forum at Hershey Swap meet; 2 of his buds were interested in finding 5 speed gearbox parts, maybe someone here can help with the supply???????