Gear vendors overdrive
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,164
Likes: 7
From: Beringen
Gear vendors overdrive
I just looked at their add on overdrive kits. Anyone ever use these ?
http://www.gearvendors.com/aghr4sm.html
http://www.gearvendors.com/aghr4sm.html
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
no, but I want one. Have a new Autogear M22 with a Tom's 411. They will handle all the power you can throw at it. Posted about this before and they are the best OD option in my opinion. 
Last edited by 63mako; Apr 13, 2008 at 11:41 AM.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
It is an automatic, electronicaly controlled unit. Shifts instantly with a push of the button in any gear. No time lost on shift. I rode in a 50 Merc with one and it is slick.
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
I heard 2 small notches in the tunnel where the upper case bolts are needed in some applications. You also need a shorter driveshaft. I have checked on this upgrade with Gear Vendors. I really like this unit but it is very expensive. A Hurst T handle with a button is the trick setup. I have seen some posts on the TKO where they have vibration issues that are difficult or impossible to sort out and others work perfect from day 1. That is the only thing holding me back from selling my Autogear and going 5 speed. I would hate to spend $3500 on a 5 speed and have vibration issues I can't resolve.
It would be pretty cool on the highway to shift to 4th standard to pass then upshift to O/D without pushing in the clutch and turning the 4.11 to a 3.20 to cruise.
I have seen some posts on the TKO where they have vibration issues that are difficult or impossible to sort out and others work perfect from day 1. That is the only thing holding me back from selling my Autogear and going 5 speed. I would hate to spend $3500 on a 5 speed and have vibration issues I can't resolve. It would be pretty cool on the highway to shift to 4th standard to pass then upshift to O/D without pushing in the clutch and turning the 4.11 to a 3.20 to cruise.
Last edited by 63mako; Apr 13, 2008 at 04:49 PM.
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Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,164
Likes: 7
From: Beringen
I don't know, but to keep the gearspread of the close ratio muncie this would be a good choice. However the OD is a little on the small side, keeping me around 3000 at 75 with a 4.11 in the back.
Price sounds not that obnoxious when compared to the 3300 $ for a tko.
The fact that there are not many people who have done this conversion, makes me fear that it could be more difficult than just two dimples in the trans tunnel.
Price sounds not that obnoxious when compared to the 3300 $ for a tko.
The fact that there are not many people who have done this conversion, makes me fear that it could be more difficult than just two dimples in the trans tunnel.
Melting Slicks
Joined: Mar 2006
Posts: 2,465
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From: Orange Park Fl
I looked at these and decided to go with a 700r4. Unless your engine puts out more power than a 700r4 can handle (which would be ALOT!), the Gear Vendors does not make sense. It is more expensive, has less overdrive, and to quote a forum member who installed one "They lie out of a dark smelly place when they say the installation is not difficult." God bless, Sensei
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
I looked at these and decided to go with a 700r4. Unless your engine puts out more power than a 700r4 can handle (which would be ALOT!), the Gear Vendors does not make sense. It is more expensive, has less overdrive, and to quote a forum member who installed one "They lie out of a dark smelly place when they say the installation is not difficult." God bless, Sensei
The nice thing about the Gear Vendors unit is the gear spread is well matched for the Muncie Close Ratio. Your effective rear gear in OD is 3.20. Keeps a Built small block in a good useable RPM range @ 70 or 75 mph.
Last edited by 63mako; Apr 13, 2008 at 10:25 PM.
Race Director
Joined: Sep 2002
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From: San Diego - Deep Within The State of CONFUSION!
I used to sell them for motorhome use. Can't say how well the Vette would do with that short a driveshaft (you need to cut off a foot). Could you make the pinion angle correct?
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,164
Likes: 7
From: Beringen
He has a manual trans and a 4.11. Wants to keep his manual. Same situation I am in. A TKO has too low of first gear for me. Means changing out the rear gear to get the most out of the TKO. Other options are Richmond 5 speed (expensive and not quite the ratios I want) or 6 speed (lots of mods), T56 (lots of mods)T5 (Lots of mods and weak if high HP). If you want to keep the 4.11, have a lot of HP, and not go internal rail shifter your options are limited. The nice thing about the Gear Vendors unit is the gear spread is well matched for the Muncie Close Ratio. Your effective rear gear in OD is 3.20. Keeps a Built small block in a good useable RPM range @ 70 or 75 mph.
The nice thing about the Gear Vendors unit is the gear spread is well matched for the Muncie Close Ratio. Your effective rear gear in OD is 3.20. Keeps a Built small block in a good useable RPM range @ 70 or 75 mph.The overdrive is only usable with first and fourth, second and third end up being the same ratio as resp. third and fourth in a normal M21/22, effectively making it a six speed...
I would go this route, but I don't even want to consider cutting up my trans crossmember or trans tunnel. Dimpling i could live with however.
Thread Starter
Melting Slicks
Joined: Mar 2002
Posts: 2,164
Likes: 7
From: Beringen
I looked at these and decided to go with a 700r4. Unless your engine puts out more power than a 700r4 can handle (which would be ALOT!), the Gear Vendors does not make sense. It is more expensive, has less overdrive, and to quote a forum member who installed one "They lie out of a dark smelly place when they say the installation is not difficult." God bless, Sensei
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
They DO have experience with Vettes and even sent me photos of the install. They cut out either two or three places in the tunnel (I don't remember exactly). Then they put in the overdrive, some padding as a spacer and re-fiberglassed. They said later C3's with a metal tunnel could get away with denting the tunnel out (dimpling) but might still need some cutting. The install was obviously do-able, but as I said before, I PM'ed a forum member after I did a search for "Gear Vendors" on this forum. He was the only person I saw who actually had installed one. Seems his name was Wayne, but I don't remember exactly, I haven't seen him around in years. He said the install was difficult. God bless, Sensei
Tech Contributor
Joined: Aug 1999
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From: Connecticut, USA
My buddy has one in his 78. My back hurts looking at that moster. It's hooked to an M-22 rock crusher in fact that I'm supposed to rebuild when I get some free time!! The DS is short and I don't know how he got it out but he did. He switched over to a removable cross member too. It bolts to the main case, the tail housing is removed.
If it were me I'd go with a 5 or 6 speed.
If it were me I'd go with a 5 or 6 speed.
