switching out T5 trans to 4L

racinemg1 · August 02, 2008, 11:41:13 PM

Had to sign up as a separate user since I needed to post this for my dad and I can't remember his user name & password off the top of my head...anyway,

switching out T5 trans to 4L 60 overdrive trans beind a 3.4 in MGB. Any advice?

Thanks,
Dan
(racinemg)

BMC · August 03, 2008, 08:14:21 PM

Dan,

I would be interested in knowing why your considering the automatic.

Its the 4L60? Not the 4L60-E?

From my understanding, the 4L60 is the 700R4 with a new numbering system. I may be wrong.

The 4L60-E that came along in 1994 behind the 3.4L Camaro V6 requires a PCM or aftermarket controller or one from GM performance. Big bucks.

Also, a little more of what I understand:

4L60-e 1994 to _____

4L60, just a designation name swap, probably only used in 1993.

700R4 1985(?) to 1992.

-BMC.

Citron · August 04, 2008, 10:10:52 AM

Dan,
I uses a 700 R4 behind a 3.1 in my GT. I had to cut out a section on the passenger side and make a box t cover it.
The trans is pretty wide on the right side. I really like the auto box for around town use and the .7 overdrive is good on the open road.
Mine is one of the early trans that uses a TV cable and an electric lock-up for the converter. The after market sell lock-up kits.
I went to my local parts place and bought a trans cooler and mounted it in front of the AC condenser. I have had no troulbe with the trans. I did have a kit put in so that I could run full throttle in fourth gear. Otherwise it down shifts to third whenever you floor it. Now it will down shift if the speed is below about 70, but not otherwise. It does not affect the other down shifts at all.

Steve

racinemg · August 04, 2008, 02:22:04 PM

I'm considering the automatic b/c the clutch pressure has caused tendonitis in my left ankle (believe it or not!). And last May I had a lung transplant and prior to that, had 8 stints put in my heart. It's just a matter of being too hard to drive and it's getting worse. Unless a bigger solenoid or a mechanical advantage built into the clutch pedal itself. I did replace the two speed power glide transmission behind the 283 in my chopped & channeled Model A coupe on a '32 frame with the 700R4. And the after-market controller my mechanic said wasn't too expensive. But it wasn't a V6. Thanks for the info.

racinemg · August 04, 2008, 02:24:49 PM

Steve, How big was the box you had to cut in the right hand side of the tunnel? Thanks for the info. Dan

Citron · August 04, 2008, 02:59:58 PM

Dan,
It is under carpet now. I seem to remember that is was ABOUT 4 to 5 in long by 2 high by 2 deep.. Not very big.

Steve

BMC · August 05, 2008, 12:53:40 AM

Steve's car is a pleasure to drive. Glad I got the chance at the meet to exchange keys.

From my understanding the GM stand alone controller is costly. Maybe there is another one on the market? If so, most likely the price has got to be less than what GM had out a few years ago. I am not into automatics but the GT we have is supposed to be converted to an auto for my wife. For my own future, I may be forced into an automatic as well, just not yet. I am not totally against automatics but just have a feeling that they take away from a little bit of the work that makes the driver a participant in driving.

-BMC.

jimbb88 · August 06, 2008, 10:24:43 PM

You might want to look at a 200R. It is a lot smaller than a 700R and good for about 400 HP. It does not require a computer and the lockup can be a simple switch. They are available in "GM" and "Chevy" bolt patterns.

Citron · August 07, 2008, 01:25:19 PM

The 200 r4 was never used behind the 60 degree v6's. The bolt pattern will not match up.

Steve

BlownMGB-V8 · August 08, 2008, 05:21:11 PM

Yep, he's stuck with the 700 but that's not all bad even if the gears aren't as ideal. The MegaSquirt can be used to control the 4L60E as well as port injection, is very tunable and not overly pricey.

Jim

BMC · August 08, 2008, 11:31:44 PM

I don't recall the designation for the unit previous to the 700R but think it was the turbo 350?

Jim,

I had no idea the Megasquirt was that good as of yet. I guess I am stuck in the MS of yesteryear- about 6 or 8 years ago.

-BMC.

Citron · August 11, 2008, 10:50:27 AM

Dan,
Another problem with using the 700 is IF you have a carb, then the carb must be raised to allow the TV cable to work. Other wise the linkage will hit the valve cover. I have heard of people turning the carb 90 degrees instead of putting in a spacer, but have not seen one. I put in a spacer and then used a hood scoop to clear everything.
If you are fuel injected then it shoudl not be a problem.

Steve