[johnnybegood]

I have a 75 corvette and it has a good th400, but i want to put in a transmission with overdrive.
I have a 87 cady with a 700r4 overdrive would that be worth it or wait for a better one. the cady is 4 door
and its heavy, so the vette should have no problem.
any advice would be greatly appreciated.
Thanks Johnnybegood.

[ October 10, 2002: Message edited by: johnnybegood ]

[ October 10, 2002: Message edited by: johnnybegood ]

[ October 12, 2002: Message edited by: johnnybegood ]</p>

[trees]

Go for it! If my memory is correct, the 700R4 is almost 2 " longer than the TH400, so you will need to have a shorter drive shaft and may have to use the old Cady front yoke. I have changed TH 350s to 700R4s and am planning a couple of 400s but have not checked the output shafts yet. From experience, you may want to go ahead and have the 700 rebuilt before installing cause your limited space will make you wish you had if it goes bad. There are three ways of controlling the torque converter lock up feature that you want to consider. I have all three of them installed,(3 diff trannys) but have been operating only one at this point. It is a computer setup by Ron Francis Wire works for about $130 and it works like a champ. Painless wiring makes a non computer one for about the same price and it operates off a furnished vacuum switch and the brake light switch. I think it will work fine also. My last tranny, I installed a still different one which goes in the valve body and is entirely mechanical and is internal pump pressure activated. I can't remember the name of the unit, but it is about half the price and MUCH more simple. I'll try to bring the old box home in case you are interested. If you make it work, you are going to love it when you see your tach drop 27% at cruise speeds. The big gap between your lower first gear and higher 2nd gear will take some getting used to and the computer controlled lock up searching that can go on in the 41-44 mph range takes some understanding that you may not have recoginized in your big Caddy.

[trees]

Sorry for the long wind, but forgot to talk about speedometer drives. Don't know if your 87 Caddy has an electric speedo or not. If so, you probably want to find the tail housing shaft from a cheaper GM products' 700. Ron Francis' unit comes with a pulse generator that will let you use aan electric programable speedo, or a good speedo shop can put your rear wheels on a dyno and cut a little gear box to put in the cable line to make your speedo read very accurately. Its almost impossible to find the right gear combination withe the overdrive!!

[Deuce]

If your Caddy has a Chevrolet engine, you may be OK.

700's only come in the Chevrolet pattern.

[slider]

TCI should be able to supply an adaptor.

[Deuce]

The point is.......

IF the Caddy is not Chevrolet powered, it's not a 700. IF it is....no adaptor needed.

[johnnybegood]

Hey, Thanks for the information. I will do a lot more; "homework", before I change the trans, but you guys are great for responding to this message.
Again Thanks,
Johnnybegood.

[Vettes]

You may also want to check out the Corvette Action Center Forums at http://www.corvetteactioncenter.com/forums/index.php

They have a great group of knowledgeable vette guys there that might be able to help you out. Good luck!

[willys36@aol.com]

My standard recommendation to this type of post is go to

http://www.bowtieoverdrives.com/

They have EVERYTHING for overdrive transmissions, including excellent instructions, good customer service, patented TV cable adaptors for every carb/trans application (critical), converter lockup switches and if you give them your tire diameter and rearend gear ratio, they will sell you a set of speedometer calibration gears for about $40.

[johnnybegood]

Thanks for the FFFantastic site on the forum it is great
just like this one thank you again I love this forum