**Overdrive auto info for those looking to do a trans swap**

I found 2 more great sites for info:

http://www.rowand.net/Shop/Tech/AutomaticOverdriveTransmissionSwap.htm

http://www.442.com/oldsfaq/oftrn.htm

 

Digging around and these are what I found
83-89 were the years for the 200 R4 (there may be more but these are the most prevolent years)
Buick GN casting numbers were 3BR 4BQ 5BQ 6BR 7BR
Olds casting numbers were 3OZ 4OZ 5OZ 6KZ 7KZ
Cheby (Monte Carlo) casting numbers were 4CQ 5CQ 6CZ 7CZ 8CZ
Pontiac 9TA (V6 cars)
Caddy...there are some, but I have not found the numbers yet.
These numbers may or may not have an F behind the other numbers...dunno what that means yet either.

Cores are running about 2-4 hundred and in some areas will cost as high as 1200.00 to build (at least around here where there are none of these laying around)

Wayne S

 

2004r

Lot of good info in this thread. I just talked o a 2004R specialist in Vegas
last Friday. He is going to build one for me as soon as I come up with a core.
He said the most preferable cores are in this order. Buick GNs, Turbo Regals,
SS Monte Carlos, Full size GM V8 cars,
. He said the Caddys weren't as good because they were designed at the factory to have a soft shift. The fellow I talked to is Len Freeman in Las Vegas. Good Luck Bob Harris

 

Bump

 

Sean,

This was a really great post. I'm glad you bumped it.

 

Thanks for your contribution and everyone elses.

 

Probly new members looking to lower cruise rpm and or add taller gears....

 

I used a 200r4 best thing I ever did Call Janis Trans in Akron Ohio.

 

Great Infor, I have aquired a 200R4 which will be rebuilt this week, to be installed in the 69 GS 350. I will save the numbers matching TH350.

 

6L80E - 4.02 - 2.36 - 1.53 - 1.15 - 0.85 - 0.67

this is GM's new 6speed overdrive transmission no word on any aftermarket bellhousings as of yet nor am i sure what pattern it uses but i'm sure someone will find a way :TU:

Edit bolt pattern is the same as the lsx engines

 

I've got my 2004r torn down now, it's out of a Cutlass. But I'm thinking about a manual valve body. Maybe some of you guys can help me with a couple of questions. First, exactly what does a trans brake do? Does it disengage the driveline? Does it lock up the driveline? I'm not a drag racer so I am totally clueless about this but if it disengages the driveline it is something I might be able to use. Then if I can just adapt the line pressure controller from a 4L60E or some other computer controlled tranny I just might make it work the way I want. So what's the scoop on that tranny brake?

Jim

 

Jim, a transbrake engages 1st gear and reverse at the same time so you can rev the motor to your desired launch speed without loading up the driveline like footbraking would.

Without a trans brake you may have "creep" while trying to build rpm while footbraking.

Lots of guys have these set up with an electronic delay switch so they can reduce reaction time by coordinating the lights on the tree with the transbrake.

I just use line lockers on the front brakes but will use a transbrake on my drag only car...

If you want to know the tech specifics read this quote: (not sure where I got this but saved it.....)

"A modification to an automatic transmission having a transmission brake, especially applicable to the TurboHydramatic 400 transmission, allowing for fast, consistent release of the transbrake. The reverse servo cover is modified to add a pressure release passageway communicating with the inside of the reverse servo cover and dumping fluid into the transmission pan. The passageway is selectively blocked by an electrically operated solenoid having a shaft or needle fitting into a seat, so that when the solenoid is powered, the solenoid shaft or needle fits tightly into the seat, preventing the flow of hydraulic fluid from the inside of the reverse servo cover. When power is removed, the pressure of the fluid instantly pushes the solenoid shaft back from the seat, dumping pressure from the reverse servo nearly instantaneously."

 

i'm surprised i never linked in my ID thread from TeamBuick to this before:
http://www.teambuick.com/forums/showthread.php?t=9781

bob also has a big new page put up with a whole bunch of trans id stuff but he hasn't got it linked directly from the shop area and i've forgotten how to get to it. i'll see if i can't find that.

 

Thanks Sean, it's not the answer I was hoping for, but it is about what I was expecting. So I take it the locked up transmission is resisting the force of the torque converter until it releases, and at some point in there the driver floors the throttle and switches off the transbrake? Regrettably that does me no good, as what I'm looking for is the ability to momentarily disengage the transmission in any gear.

It appears this could be done in all forward gears by interrupting pressure to the forward clutch pack. Chris K. (who has been less than helpful on this project but I can't blame him since he's a dyed-in-the-wool drag racer) pointed out that the forward clutches would not hold up long in being used as a manual clutch but I couldn't seem to get him to understand that launching the car was not the purpose here and I'm not trying to substitute the forward clutch pack for the torque converter. There are times on a road coarse when you'd like to disengage the driveline. It allows a higher level of finesse in controlling the car's attitude in transitions, and in the hands of a skilled driver this can translate into faster lap times and is particularly helpful when dealing with traffic when at or near the limits of lateral adhesion. Almost never would any occasion arrive where the driver would want to re-engage under full throttle and high rpm (and thereby immediately going dead sideways), so the clutch pack should be relatively safe unless someone just decided to try and break it intentionally, and no transmission is safe from that.

Now it might be handy to have the same ability in reverse though exactly why I don't know, other than for consistency in the controls, but I'll be studying the hydraulic diagrams to see if there is a simple way. I'm guessing though this will mean adding one or two solenoids connected to the clutch pedal and the real question seems to be control of the firmness of re-engagement. Perhaps if I can get control of line pressure via a MegaSquirt output I can find a way to control re-engagement with line pressure.

It's starting to look like a fun challenge, so I'll proceed with clean-up and reassembly and maybe beef up the tranny just a bit since it's going behind a mild high compression 340 with a blower, I'm guessing maybe 400 hp tops. I'll be on vacation for a week and it will be a good time to do some reading on it.

If things go smoothly enough I may even look into fitting paddle shifters, though I'd have to make my own to get something I'd be happy with. More solenoids of course. Wonder if Red Hat solenoids would be a good choice?

Jim

 

Jim
are you looking at setting this up as a binary on/off on the clutch packs or with some kind of a rheostat control?

i have a hard time imagining that there's not going to be some amount of driveline shock with a binary setup ... and "at or near the limits of lateral adhesion" this can't be a good thing.

 

The problem with this one is that the controllers are internal, and it talks to the engine via a high speed databus. It uses clutch to clutch shifting and various other high tech stuff, so to control it takes a lot of input from the engine control module (07 the engine and tranny each have their own computer, but they talk to each other with a databus so to fool the tranny into thinking its behind a modern powerplant would take some work). For example, the shifts would be school bus hard unless you could get the engine to defuel during the shift, or slip the clutches which may or may not be harmful to the tranny. Serious programming required.

The 4L60/80 stuff is "easy" since it shared the same controller as the engine...and the engine controls aren't terribly complex so adapting to old engines isn't too bad I hear (although I have not really looked into it being a resto type of guy). These new engines do not use 3D VE tables though...instead they have equations that calculate VE. Engine operation is divided into 30 zones. Each zone has a unique coefficient that forms an equation with inputs like RPM, MAP, etc to calculate VE and this info is also then used for the transmission control. Getting way out of my element here, but basically, its complicated!:shock:

BUT I'll bet the aftermarket is all over it. Its the same size as the 4L60e in millions of truck and cars, so that market alone would be worth the development. For the older cars who knows....o No:

Be awesome though. Could run like 2.56 gears and still be nuts off the line...

 

Jim,
I understand your problem. The solution is manual transmission. The modifications that you are trying are going to take you into a dollar range that does not make sense IF they could be accomplished.

 

Dang good info here! :beers2:

What rear gears are you putting behind these things?

I finally found my 12-bolt (peg-legged 3.08) and figure I need to bump it up a little bit.

With a heavy car (66 A-body convertible) and a few hills I guestimated at least a set of 3.55's with 16" wheels or 3.23's with 15" wheels (or some combo in that neighborhood)...so what say the masses?

Wayne S

 

I like those numbers...and that is what I was hoping to hear.
Haven't weighed it yet...it's still in the paint shop getting the final once-over prior to paint (that and I told them I wasn't in a hurry).

The book and title list the car out as 3379#, but I have since swapped motor, tranny and rear along with the 14" steel wheels.


Now back to your reqularly scheduled program

Wayne S

 

The GN's come with a 3:42 gear and 215/65/15's (nobody keeps this size on the back!) I run a 3:73 on my Skylark with 275/60/15 drag radials (28" tall tire) Speedo is not that accurate but as near as we can tell it runs close to a true 80 at 2500 rpm.