TH-400 overdrive opinions?
Thread Starter
Instructor
Joined: Apr 2007
Posts: 113
Likes: 0
From: Big Rapids MI
TH-400 overdrive opinions?
Those of you who have installed overdrive in your th-400...was it worth it?
Where did you purchase the parts, how much was it and how difficult is it to install?
Thanks
Where did you purchase the parts, how much was it and how difficult is it to install?
Thanks
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
IMHO a add-on OD is not worth all the fartin with. Just get a built 2004R or 7004R or build the thing yourself. The 2004R is a near drop in replacement for the TH350, gives you a better first gear plus OD
Race Director
Joined: Jul 2004
Posts: 12,707
Likes: 329
From: Scottsdale Arizona
Drifting
Joined: May 2005
Posts: 1,909
Likes: 6
From: Lake Arrowhead - Georgia > 72 Base Coupe & 74 BB Roadster
This car is an absolute blast to drive, but it would really be enjoyable if a little better highway cruise milege was possible. I don't expect miracle economy from a 454 ... just a little less rpm at 70 mph would be good all around.
Race Director
Joined: Jul 2004
Posts: 12,707
Likes: 329
From: Scottsdale Arizona
As Sixfooter said above, I think your best bet is a 200-4R. I think you can buy a more robust one for less money than a 700R4. Also fits a little more easily. The down side is that they're not as readily abailable as the 700's.
Safety Car
Joined: Aug 2001
Posts: 3,686
Likes: 202
From: Waterford Mi
I got mine from bowtieoverdrives.comfor about $1700. It has been a few years so the prices have gone up. I am very happy with the setup.
Trans install
Trans install
Drifting
Joined: Feb 2005
Posts: 1,738
Likes: 2
From: San diego ca
I just helped a friend install a Gear vendors overdrive in his big block nova - the kit is complete and well documented - and the car drives great.
His only issue with going to a 700r4 or 4l60e is that his 400 is a race prepped unit that easily takes the power from the big block - and the gear vendors unit is nigh onto indestructible.
Gear spacing in a 700r4 isnt optimal for bracket racing IIRC because the 1-2 shift is too big - and with the gear vendors unit - he can turn it off and still have his totally bulletproof 400.
All said and done - I dont know what the cost of a well prepped 700r4 or 200 would be to handle 450 or so hp, I'm sure its still less than a gear vendors unit.. but hey he is happy with it - required only a shortened driveshaft - used his same mounts - and we didnt have to pull a transmission to install it.
Edit: BTW it took us about 4 hours to install it .
His only issue with going to a 700r4 or 4l60e is that his 400 is a race prepped unit that easily takes the power from the big block - and the gear vendors unit is nigh onto indestructible.
Gear spacing in a 700r4 isnt optimal for bracket racing IIRC because the 1-2 shift is too big - and with the gear vendors unit - he can turn it off and still have his totally bulletproof 400.
All said and done - I dont know what the cost of a well prepped 700r4 or 200 would be to handle 450 or so hp, I'm sure its still less than a gear vendors unit.. but hey he is happy with it - required only a shortened driveshaft - used his same mounts - and we didnt have to pull a transmission to install it.
Edit: BTW it took us about 4 hours to install it .
Last edited by fauxrs2; Jul 19, 2007 at 08:34 PM.
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Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Which OD tranny would be the best swap for a 74 BB with T400 ?
This car is an absolute blast to drive, but it would really be enjoyable if a little better highway cruise milege was possible. I don't expect miracle economy from a 454 ... just a little less rpm at 70 mph would be good all around.
This car is an absolute blast to drive, but it would really be enjoyable if a little better highway cruise milege was possible. I don't expect miracle economy from a 454 ... just a little less rpm at 70 mph would be good all around.
Melting Slicks
Joined: Dec 1999
Posts: 2,116
Likes: 156
From: Mid West
Cruise-In III Veteran
Gear vendors overdrive
I've debated about going with an overdrive in my Cutlass, but I don't think there is enough room in a C3. Have you looked at the driveshaft tunnel .... its tight! I put a 3" drive shaft in mine at one point and under hard right hand turns the body was rubbing the shaft slightly. I ended up going back to the stock 2.5" shaft size. Most cars have A LOT more room than ours do. Just look at the spacing between the seats where the parking brake is .... not wide at all. I think your stuck with going with a 200r4 like the others have mentioned.