Gear vendor overdrive
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Joined: Oct 2019
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Gear vendor overdrive
In the middle of installing one now what a pain in the azz. Had to make new tranny x member and cut off about 2 1/2 inches of trail shaft output.and stock shifter isn't going to work also. Got a tci outlaw shifter. center console don't want to think about probably make custom with foam and fiberglass. Anyone have these problems also and others I can look forward to thanks
Melting Slicks
Joined: Oct 2010
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From: "ɹǝpunuʍop", Adelaide, South Australia
you don't say what year your car is, but no, have read many times they don't fit C3 without a crap load of work..
i just used a 700R4 in my '72
i just used a 700R4 in my '72
Last edited by riverracer au; Mar 13, 2020 at 07:09 PM.
Race Director
Joined: Mar 2016
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From: Napa Valley California
I was seriously looking at installing a Gear Vendor Overdrive unit behind the TH-400 in my 73.
I gave up and went to a 5 speed manual.
The owner of Gear Vendor did install one in his early C3 and when I talked to him he told me all the work they had to do to get it to fit.
They had to, among other things, completely rebuild and widen the rear section of the tunnel so the unit would fit, which led them to modifying the seat tracks, then modifying seats so they could wedge them in to fit.
Gear Vendor will tell you it can be done but they will not recommend it.
Give them a call for what they did.
Good Luck.
I gave up and went to a 5 speed manual.
The owner of Gear Vendor did install one in his early C3 and when I talked to him he told me all the work they had to do to get it to fit.
They had to, among other things, completely rebuild and widen the rear section of the tunnel so the unit would fit, which led them to modifying the seat tracks, then modifying seats so they could wedge them in to fit.
Gear Vendor will tell you it can be done but they will not recommend it.
Give them a call for what they did.
Good Luck.
Last edited by OldCarBum; Mar 13, 2020 at 11:04 PM.
Is my vette stock?? HAHA
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2020 C3 of the Year Finalist - Modified
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I was thinking of going that way but couldnt find any info and then price scared me away. If you can keep posting up pics of your progress its going to help one of us further on down the road. Thanks for the pics so far. Nice welds on your crossmember!!! I ended up with a used McLeod 5 speed that I'm installing now
Drifting
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From: East London/SW Essex UK
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I'll take more pics still have to remove x member and paint. My friend had a small welder we just tacked it together and took to a professional welder. I should of used 1/8 inch but went with 3/16 2×3 rectangular tubing . I just bolted on the end plates and shimmied it up about 1/4 inch give me a little adjustment. Had to beat the tunnel a bit more than the guy at gear vendor told me . The seat tracks should be ok.
The price I didn't think was to bad about 2700 compared to good 700 about 1600 -2000 dollars + another 300-500 for torque converter
The price I didn't think was to bad about 2700 compared to good 700 about 1600 -2000 dollars + another 300-500 for torque converter
Last edited by Gzilla; Mar 14, 2020 at 11:40 AM.
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From: Crossville TN
The GV unit is very expensive and the design is overkill for the purpose in most cases. It won't easily fit in a C3's driveshaft tunnel and it isn't a "seamless" product from an operational standpoint. It is still interesting to find how it fares in a C3 and whether it is viable as an alternative to an O/D manual or auto transmission. In terms of being able to keep the vehicle as close to original as possible, not sure how to judge that with another chunk of equipment in the system which requires body modifications.
Team Owner
Joined: Jan 2006
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From: Crossville TN
The GV unit can handle a TON of torque. MUCH more than most C3's could ever dream to put out. Unless you are doing some mighty heavy 'pulling' with your car, it's doubtful that it's capabilities would ever be tested significantly. If they made a smaller unit for lower power, then it might be viable. Right now, the best choice for MOST folks is to install an overdrive manual or automatic transmission.
Drifting
Joined: Oct 2005
Posts: 1,527
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From: East London/SW Essex UK
The GV unit can handle a TON of torque. MUCH more than most C3's could ever dream to put out. Unless you are doing some mighty heavy 'pulling' with your car, it's doubtful that it's capabilities would ever be tested significantly. If they made a smaller unit for lower power, then it might be viable. Right now, the best choice for MOST folks is to install an overdrive manual or automatic transmission.
For me the perfect transmission would be a M21 with stock ratios and a 30% or 40% overdrive 5th gear. Which is almost what a Gearvendors or Hone unit would provide.
Is my vette stock?? HAHA
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2020 C3 of the Year Finalist - Modified
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I'ld love one if they were smaller
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Or turbo 350 like mine
the manual has a page on racing they say you usually go from 1st -2nd-2nd over- 3rd and if you run out of gear overdrive .if your had a 700r4 you would probably hit 1st over because of the big drop.
the manual has a page on racing they say you usually go from 1st -2nd-2nd over- 3rd and if you run out of gear overdrive .if your had a 700r4 you would probably hit 1st over because of the big drop.
Last edited by Gzilla; Mar 16, 2020 at 10:36 PM.