GM 4L60e 4-sp conversion (Jensen Interceptor)

[PhilipL]

A good V8 needs an appropriate transmission behind it.

My Jensen Interceptor was running 3100rpm at 120km/h in 3 with its original Chrysler A727 transmission. This simply would not do in this day and age.

Now its running with a GM 4L60e (electronically controlled) transmission and now its doing 2000RPM at 120km/h (in 4th, with torque convertor locked)!

The transmission is being controlled by a Megasquirt product called GPIO and its running the "Extra" Transmission Control firmware.

A comprehensive thread on this conversion can be found here:http://www.joc.org.uk/phpBB2/viewtopic.php?f=4&t=17192

Feel free to ask questions if you have any.

[JSF55]

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[PhilipL]

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Any questions I could help with?

[JSF55]

Just something to read on a Saturday night, was looking at the gearbox controllers before

[PhilipL]

was looking at the gearbox controllers before

OK, read about the GPIO (TCU) hardware here: http://www.msgpio.com/manuals/index.htm

You can now choose which firmware (the software that runs on the hardware) you want to run on the GPIO:

1) Megashift: http://www.msgpio.com/manuals/mshift/4L60e.html

OR

2) Extra: http://www.msextra.com/product-range/ex ... n-control/

I'm running the Extra FW is perhaps easier to configure but less feature rich than the Megashift FW. The Extra FW can also run on the "Microsquirt" pre-assembled hardware which eliminates the physical build of the TCU if you are not that way inclined.

[JSF55]

Thanks phillip, not looked at phils site (extraefi) for a while, should make a good read

[Eliot]

I remember looking at a prototype of that years ago - I think James wrote it over one weekend - we were both looking at 4L80e's at the tine.

Have you upgraded the internals of the 4L60e? - Out of the box they are not particulary strong, especially with that 440 in front of it.
I've driven a 440 powered Dakar and it had the same low end grunt of my 350 turbo chevy - and I broke the 700r4 (a Manual 4L60) many times before i found a combination of parts that would last. It works well now and I subsequently sold the 4L80e setup.

If its anything like the 700r4 you want your line pressure at around 200psi when putting maximum torque through it. Listen/feel for slipping going from 2-3 and 3-4. Dont apply the TC under heavy load - as the clutch inside it is tiny (unless you are running an aftermarket one that allows WOT lockup)

[M ICHAEL ROGERS]

Why didn't you use the MoPar 727 with OD? The club has featured it in the mag?












/
Michael Rogers
NTERCEPTER ii

[dyno]

Dear PhilpL,

How many solenoids are fitted into this gearbox and how many are used for switching gear?

Do you have the layout of this switching pattern? In a ZF gearbox only 3 solenoids are used for all 4 gears. Very easy to manipulate.

Do you run this gearbox behind a Rover V8 ? Are there any bellhousing that fit Rover V8 ?

regards

Dirk

[dyno]

sorry, 2 solenoids in ZF, not 3

[DaveEFI]

Late SD1 have a GM box with detachable bell housing. I've often wondered if a later 4 speed (or 5) GM box could fit to that.

[dyno]

I was hoping, exact the same. If pattern is still the same. As far as I found out the "attachable" boxes seems to use the same pattern. Of course, does not mean it's still the same as the very early boxes but you never know.