Inliners International Forums General Discussion Vortec 4200 vortec 4200 w/ auto transmission

I have read , many times, the posts on the 4200 and have some 4L60 related questions. I have a 2002 motor and trans combo, but still has the 4wd transfer case attached to the rear of the trans. I am wanting to run the auto as it will be a daily driver with low boost turbo. My question is can this particular trans just have the 2wd tailshaft/tailhousing swapped and be a viable trans? You guys athat are running teh auto, what have you done? Any suggestions on basic upgrades to make it last behind this motor. What controllers are you using? Looking forward to your input.

You can swap the tail/shaft housing. I think your year uses the 6 bolt tail housings found on 1998-2002 f-bodies. Take everything from the donor since speed sensor is gear driven on 2wd and yoke is different. 4L60 is not a great tranny for turbo, but if your putting it in something a whole lot lighter than the 4600 pound SUVs it came in, it can be built.

You will need to dissassemenble the transmission completely to swap the output shaft as it is the first part to be installed.

The 4L60 can be built to handle the power - it needs some of the hard parts changed. Check http://www.700raptor.com/

For > 450HP the following should be upgraded:

sun shell
front and rear planetaries
sprag
output reaction carrier
input shaft and drum
3-4 clutch
band (wide band)
direct clutch
front pump - need mod's for higher output
boost valves
1-2& 3-4 band servo's
valve body mod's to speed up shifting

Not cheap but can be done.

Yeah, that was what

Weird, cut off the rest of my message. That was what I was thinking on the trans. I knew we would have to tear the trans down due to the tailshaft having to be removed. Is the only way to control shifting by using a $500 TCI controller or is there a way to make it shift for normal driving applications. There has to be some kind of way we can put an automatic behind the motors without it being so costly. If we are to try and develope this into a usable motor for our old cars/trucks the cost of transplant has to come down. I remember a post where one gentleman had an adapter made to bolt a regular automatic to the 4200, but at a cost of 2500bucks...that just seems like the machinist needed to pay off his mortgage. The last very custom adaptor I had made by Pat out at Wilcap was for putting a 200-4r behind a Cadillac flathead and it was 500 bucks for all adapter plates, flywheels , etc etc.

Soon Megasquirt GPIO will support the 4L60E, hopefully before May.

Another approach if you didn't mind having really firm shifts would be to shift the trans manually, it would take a custom built shifter with 2 HD mirco switches that would operate the shift solenoids according to the GM manual shift sequence.

With a some thought one could build a circut to monitor a TPS sesnor and then PWM the line pressure solenoid. 0% (off) = full line pressure ~75% = idle line pressure. A vac. switch could be used to lock up the converter when in 4th.

How handy are you with electronics?

Are you going to use the stock computer (PCM) that was mounted to the intake? I think that it will control the Trans for you. I don't think the Trailblazer needed a separate trans controller because the PCM was an all-in-one unit.