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  #1  
Old 10-16-2007, 10:06 AM
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Default Transmission Upgrade question

I am thinking about the possibility of upgrading my transmission to a G50..

What is the usual price range
Should I consider a rebuilt

I know I could possible use my fathers garage for swapping out a transmission so I would at least save on labor.

Educate me on this..What are the benefits, pitfalls etc..

or should I consider rebuilding mine and what am I looking at for price...I do not have a garage so I am not able to do mine at home. and I would not want to utilize my fathers for that amount of time nor make a huge request from the Dorki crowd.

I just want a smooth solid easy throw and goes into first gear everytime..
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Old 10-16-2007, 10:09 AM
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Scott,

If you ever decide to club race your car, at least under the current rules, you'll be bumped into the GT class with a different tranny. If you have no plans to race the car, then disregard this liability.
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Old 10-16-2007, 10:22 AM
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Well, I can't say what it would take to do the G50 conversion. But, just a guess, it will be by far cheeper to rebuild your 915? than put a G50. Especially, a G50 that has been rebuilt.

My understanding is that 915's aren't that bad to rebuild and are a DIY potential (read as, even though you are not DIYing it, it will be cheeper to have a pro do it and parts are cheeper to IIRC) and G50 rebuilds are... well leave them to the pros.

I'd rebuild yours as, although I do not have a 915, I understand that a properly set up one is just fine.
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Old 10-16-2007, 10:24 AM
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Wevo mounts, Charlie's bushings, Seine shifter, that's what you need instead to achieve shifting bliss.

G50 has a hydraulic clutch, not cable actuated, plus it's larger and bulkier. Not an easy swap as I understand it...
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Old 10-16-2007, 10:25 AM
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A G50 doesn't just bolt in. The transmission is too large to fit into the car with the old style torsion bar tube in the back. To make this work you can:

1. Go to coil overs. Cut the torsion bar tube out of the middle and reinforce everything, because the tube is actually a structural member. And reinforce the rear suspension points, too, because they weren't designed to take the spring load of the rear suspension.

2. I think I remember reading about guys getting the G50 bellhousing machined down so that with a shorter G50 and moving the engine back a bit, you can just make it work. Do a search on Pelican for that, it's been a long time since I've seen anything about it.

Cost? Here's some guesstimate numbers assuming #1: $3500 for a used G50. $1k for clutch, flywheel, etc. $1500 for coil over stuff. $1500 for welding work. $1000 for other stuff (hydraulics, pedal cluster, trans mounts). Total - $8500.

My guess is option #2 is similar in cost - replace welding costs with machining costs. Drop the $1500 for new suspension and maybe that option works out to $7000.

Neither are cheap options. And in the end you have this Frankenstein that, regardless of what others tell you or you may think, is not worth what an original car is worth. Hell, you might be better off to sell the car and get a newer turbo after all that.

But, in the end, I think getting the 930 trans reguilt is the best option. Probably cost you $3000 with you doing the pull and reinstall.
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Old 10-16-2007, 10:25 AM
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Quote:
Originally Posted by Mark in Baltimore View Post
Scott,

If you ever decide to club race your car, at least under the current rules, you'll be bumped into the GT class with a different tranny. If you have no plans to race the car, then disregard this liability.
Clarify racing..I have just dipped my toes into the water and did a HPDC..I want to do DE's and possible autocrosses..
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Old 10-16-2007, 10:28 AM
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Quote:
Originally Posted by vascott99 View Post
Clarify racing..I have just dipped my toes into the water and did a HPDC..I want to do DE's and possible autocrosses..
Racing is, well, racing! PCA Club Racing, mainly. Not sure about SCCA classification rules. NASA is power-to-weight, but don't know how they feel about these types of mods.
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  #8  
Old 10-16-2007, 10:45 AM
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Rebuild the 915. You can make the 915 shift smoothly if rebuilt properly and you add the Wevo or similar. I suggest you ask on RL for a reco on a shop that makes a living rebuilding 915, even if you have to ship to them.

G50 is heavier and as Jazz said not a bolt on. You'll end up with something that no one else may want to deal with when selling.
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Old 10-16-2007, 11:01 AM
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One thing to remember - your trans is a 930, not a 915. Similar, but not the same. There are some parts in there that are considerable more $$$$ than the 915 part (bearings mostly).
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  #10  
Old 10-16-2007, 11:03 AM
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Quote:
Originally Posted by vascott99 View Post
Clarify racing..I have just dipped my toes into the water and did a HPDC..I want to do DE's and possible autocrosses..
DE's and autocrossing are not PCA club racing. There are no equipment rules in DE's. Not sure about autocrossing rules, though. The bump to GT applies only to PCA club racing. It might apply to NASA racing, but I am not familiar with the rules.
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