[daduck]

I located a 700R4 that was bolted to a corporate engine in an 84 Trans Am.
Did that year tranny have Pontiac V-8 bolt pattern?
How can I tell Chevy bolt pattern from BOP?

Thanks,
Dave

[abefromen]

Originally Posted by daduck

I located a 700R4 that was bolted to a corporate engine in an 84 Trans Am.
Did that year tranny have Pontiac V-8 bolt pattern?
How can I tell Chevy bolt pattern from BOP?

Thanks,
Dave

700R no unibell.
200R had unibell
700R needs adapter to go BOP

Someone slap me if I'm wrong.

[Sirrotica]

700R4 is chevy only bolt pattern, you can adapt it to BOP engine with a simple adapter plate. I included a link to JEGS chevy transmission to BOP engine:

https://www.jegs.com/i/JEGS/555/60172/10002/-1

FWIW, the stock 700R4 isn't going to last forever behind a 455 Pontiac, you'll need some stronger hard parts to assure longevity. Building a 700R4 to last isn't exactly cheap.

A 4L80E has the same inside parts as a T400 with added OD, it was designed for roughly 450 HP in stock form, and is easily bumped up to 700 HP with minor modifications. It however isn't cheap to retrofit to older cars and requires an electronic controller. It also is chevy only, bolt pattern

Then there's a 200 4R, not cheap either to build to withstand the power of a 455 either, and is probably the weakest of all 3 in stock form. It requires almost every hard part in the transmission to be upgraded, not cheap either. Most 200s have dual fit bolt patterns.

Your car, and your choice....

[daduck]

thanks for the replies.

The 1977 Grand Prix has a low compression 400 in it now.
I looked for a used/core 200-4R locally but no luck...only option there is pay big bucks for an upgraded 200-R4.

I would think a 700R4 would last a long time behind the low comp 400.
Thanks to Brad for the link to the adapter plate.

4L60/4L80 requires electronics and so does Gear Vendors so I am leaning away from those options.

The 455 is a future project.
with a OD tranny I could swap the 8.5 rear gears (2.41) for a 3.23 and move the Grand Prix more efficiently.

[Sirrotica]

The condition of the 700 is going to be the key, if it's in good condition it should move the car around for awhile. With 180 HP it's probably going to work for your needs.

I went through all the research of ways to get OD behind a 455,450 HP street car many years ago, my choice was the 4L80E, after careful consideration of every option. That was my choice, and was reinforced after owning 3 chevy trucks with the 4L80E, and seeing how dependable it was. It's of course the strongest, and costliest option too. I only want to do it once though, so it makes sense for my car, and situation.

[77 TRASHCAN]

I've read that the earlier 700R4 transmissions are not as user friendly, when upgrading or even rebuilding them to a stock spec., 1984 I would consider an early model...

It's been a while since I heard or read of this, so be wary of the trans you spend good money on. A lot of things have changed in the last 20 years. Someone may have found a solution(s) to the 700R4 Early transmissions. It only takes $$$.

[Jack Gifford]

Originally Posted by daduck

... I could swap the 8.5 rear gears (2.41) for a 3.23 and move the Grand Prix more efficiently...

If you go with a 700R4 you might want to try driving it before swapping rear gears. First gear in the 700 is really steep- 3.??

[Goatracer1]

I replaced a T400 in a weekend with a T200-4R using the original shifter and driveshaft with a T350 yoke. No it was not cheap but it was easy. I used a 5 disc lockup converter with a high stall speed for the best of both worlds. The car weighs 3550 lbs and the engine makes 586 dynoed HP. You say it won't last behind that HP? That was 20 years ago and I've had NO problem with it. Secret, get it built correctly.

[thepontiacman]

If you need a 200R4 core to rebuild, I have it available in Talladega AL. thepontiacman@yahoo.com

[daduck]

update to this subject.....
Found a 200-4r (local) that has CQ code (1985 Monte Carlo SS) with driveshaft and a barely used Torque Convertor.
I will pull the pan this weekend and see what it looks like.

Thanks for all the responses.

Dave

[Roofy]

If you have a car with a TH350, a BOP or unicase 200-4r will be a direct swap with only needing to move the transmission crossmember, and the addition of a kickdown cable bracket to your carburetor flange. I believe that a th400 equipped car will need a different yoke or maybe a different driveshaft. It was a super easy swap in my 70 Lemans, and the gearing in a 200 is much better than a 700r4. Also, the 200 gets a bad rap, but they were behind the Grand Nationals and Turbo Trans Ams, and will hold plenty of power with some minor upgrades. I had mine gone through by a reputable transmission shop in my area of Ohio and the transmission was flawless.

[stevep]

If you do use a 700 R4, you do not want anything earlier than 1988.

[Half-Inch Stud]

4L80 all the way, and does NOT require a controller. Simple switches for 1st, 3rd, 4th, and Conv clutch. Same JEGS adapt plate. Stock Converter is a darn good piece!

Paddle-shift or do what i did and make the switches happen on your floor shifter.

[Formulabruce]

Originally Posted by daduck

update to this subject.....
Found a 200-4r (local) that has CQ code (1985 Monte Carlo SS) with driveshaft and a barely used Torque Convertor.
I will pull the pan this weekend and see what it looks like.

Thanks for all the responses.

Dave

Couple thoughts.
1. Get a remote transmission cooler, and install it up front.
2. Re use or get a NEW .... ONE PIECE .. transmission pan gasket thats rubber.
3. Get a new or rebuilt lock up converter. You don't need a
High stall and it Must be a lock up converter.
4. Don't run synthetic fluid unless it has always had it.
5. Only need the 1 wire from the front lock up solenoid to run the lock up power of 12 volts you can put on a switch.
6. Get an adjustable TV cable and make the adjustment correctly.
Most factory 200's shift like mashed potatoes. That said, if easy on them and keep them cool, they can last.

[Overkillphil]

Originally Posted by daduck

update to this subject.....
Found a 200-4r (local) that has CQ code (1985 Monte Carlo SS) with driveshaft and a barely used Torque Convertor.
I will pull the pan this weekend and see what it looks like.

CQ is a good unit, has the right valve body, governor etc. for approx. 5000 WOT shifts and better part throttle shift points/firmness.. It also had the better convertor. Just make sure the VB and Governor haven't been swapped out during a previous rebuild etc.

I have a bunch of 200-4R's in my cars including a CQ in my 70 GTO (stock 400 w/Pypes exhaust, H-O Racing Qjet & Dist. kit) since the early 90's. I pulled it out of an 85 Monte SS that was wrecked and the trans was bone stock. I put it in the GTO, only changing the filter and fluid. It's still going fine.

I have a BRF (Buick GN) unit in my 462 Formula (KRE heads, HR cam etc.) basically the same recipe as Cliffs Ventura (except for the trans). Last rebuild on that one was late 1990's and has performed like a swiss watch. I originally installed it in 1988.

I have a few others in my older Pontiacs as well, they have been reliable and trouble free with the exception of 2 times where I chose the wrong builders. Thus, the builder is the key!

Regarding the 84 700-R4, the first few years (82-84) are some of the worst as they really didn't get any major updates until @1986, then more came later. The 84 can be updated but if you really want one, I'd look for a later unit (pre-4L60E) to begin with. Also, the 700-R4 will not shift to 4th at WOT and will require you to back out of the throttle, otherwise it will stay in 3rd. Conversely, the Hydramatic Div. designed the 200-4R to shift to 4th at WOT from day one. I won a few hairy street races back in the day thanks to 200-4R's shifting to 4th on the top end and pulling away from from my 700-R4 opponents.