Gear-Vendors Overdrive
Le Mans Master
Joined: Oct 2010
Posts: 6,937
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
I've heard it can't be done and I've heard it can be done, but no one i recall ever chimed in with details.your in Potomac, i used to live in Fairfax county. weathers better here.
Intermediate
Joined: Nov 2013
Posts: 49
Likes: 16
From: Ohio
I put one on a '63 roadster a few years back. Quite a bit of tunnel modification needed to squeeze it in there. Also had to raise the seats a bit to clear the bubble in the tunnel. '63 seats had height adjusters so this wasn't a problem. Pretty nice once its all done. Car had also been converted to removable tranny cross member. Hope this helps.
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
I looked at the same mod a couple of years ago but went with an uprated 200R4. no mods to the body or drive shaft required but do need to consider final drive ratio.
Drifting
Joined: Apr 2005
Posts: 1,917
Likes: 451
From: Central NJ
Then again........."if" you get it to work----please pm me and let me know so I could do it.
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Drifting
Joined: Apr 2005
Posts: 1,917
Likes: 451
From: Central NJ
Burning Brakes
Joined: Mar 2014
Posts: 904
Likes: 46
From: Crestline CA
Doesn't really answer your question but have you thought about a 4l80e or a 6l80e? Both would require and controller and likely some tunnel/crossmember mods but both can handle alot of power, give you some really nice ratios and a lock-up torque converter as well. Ive pondered a GV unit in a few past builds but compared to a nice OD auto trans it never seemed to make sense.
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Melting Slicks
Joined: May 2002
Posts: 2,717
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
it will work, someone here posted they installed one in there car and it works great. they have short units that will work. I went with a 200 due to ease but for the money when you get to big HP the TH400 and a GV unit may be the way to go.
Neal
Neal
Le Mans Master
Joined: Oct 2010
Posts: 6,937
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
looking at their web site, they have an ultra short unit that requires cutting the output shaft 2" . that may work, and maybe some hammer work. gear vendors saying it won't work may be akin to Edelbrock saying the R.P.M air gap won't fit under the stock hood.
however, the GV unit is $2600.00 building a turbo 350 with a shortened shaft has to cost a little all in it has to be close to 4k . which puts me in the position of a 5 or 6 speed or a warmed over 200 4r . seems like 4-5 k is the magic number anyway you go. there is no free lunch.
however, the GV unit is $2600.00 building a turbo 350 with a shortened shaft has to cost a little all in it has to be close to 4k . which puts me in the position of a 5 or 6 speed or a warmed over 200 4r . seems like 4-5 k is the magic number anyway you go. there is no free lunch.
Thread Starter
Safety Car
Joined: May 2006
Posts: 3,696
Likes: 490
From: Potomac MD
Thanks for input
Always good to see what people have done out there. We are looking to keep electronics simple so a T-400 and a GV is pretty simple now with GV's new controller that makes it a seamless transmission when driving around - automatically shifts into OD at 50 mph when just cruising around and click it off if you want to do it manually. I have one in a Chevelle works great.
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
Look at a 4L80E .. Nothing your 540 has can break it, 1000 hp a 4l80e will laugh at .. . Yes you have some electronics to buy however a Fast controller will even allow you to use a 6 speed valve body..
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
There are a 100 ways to get a 4l80e avoid these guys with 5k or 7k tranys ,, Ask the local corvette club who they trust locally for transmission work and have it built by him. Order your valve body on lne as well as the torque converter
Racer
Joined: Mar 2013
Posts: 423
Likes: 25
From: Boca Raton Florida
Thank you for the advice. Going to see how long the 400 holds up after I get the rear install finished and get the car tuned on the dyno. It was new when I bought the car with no fluid in it yet so keeping fingers crossed they built it nice.
Racer
Joined: Jul 2008
Posts: 338
Likes: 4
From: Bowling Green Kentucky
Contact Rick Johnson @ Gear Vendors. He can give you the all of the info on the GV overdrive units and fitment on the C3's.
rick.johnson@gearvendors.com
rick.johnson@gearvendors.com