Transmission for 393W-- 4R70W???

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Apr 6, 2011
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As some of you know I am building a 393w with a PD blower on top of it, I know my current T5 will not handle the kind of torque the 393 will put down by any stretch of the imagination. I was considering swapping in a 4R70W and using either a manual valve body or building myself a TCU.. [I already have the micro needed to do that]
My real question is what can i find one of these out of that will bolt up to the windsor and how much TQ can one of these reliably handle?? I plan on doing any work on the trans myself and I know almost nothing about the inside of one of these auto's.

edjumakate me
 
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Ill say this about that..

A 4r70w properly self prepped w/a transgo valve body modification is behind the monster. It needs the typical hi-PO clutches, and bands...a hardened input shaft ( 2 pieces) and somebody in a trans shop that can compress the clutch packs to get the things back together after you've put the clutches back in the new order.
After that, you gotta decide if you're gonna control 4th gear and converter LU electronically through the ecu, or a couple of el cheapo switches..
 
Ill say this about that..

A 4r70w properly self prepped w/a transgo valve body modification is behind the monster. It needs the typical hi-PO clutches, and bands...a hardened input shaft ( 2 pieces) and somebody in a trans shop that can compress the clutch packs to get the things back together after you've put the clutches back in the new order.
After that, you gotta decide if you're gonna control 4th gear and converter LU electronically through the ecu, or a couple of el cheapo switches..
whats all that cost mike?
 
The trans parts were a couple of hundred...the transgo kit was another couple of hundred. The custom stall 10" lu converter was 500 IIRC...bringing the whole transmission to about a thousand, maybe a little more.

The transgo valve body is gonna require a shifter capable of 3 forward gears...( I know a guy that will give you his old one if you can stand a ratchet shifter) you'll obviously be able to modify your ecu to handle switching it in/out of 4th and L/U if you choose to add a lockup converter..( some guys forego the l/u in the converter when building big power,...As for me I wanted 2500 RPM AT 75 mph w/3.73's) you'll have a vacuum modulator that will be inside the transmission in place of the transmission control valve, and you'll have to run a vacuum line to your intake. Additionally, you'll have to to add the one way valve kit to keep boost pressure from hurting the VM. Transgo makes that thing too. ( 50.00)

It was half the price of the Bauman control kit, or the silverfox manual valve body ..But......if you are a computer kinda guy,...:rolleyes: You may be able to just build your own TCM from the DIY kit and leave all that electronic sht inside the trans.

I'm completely satisfied with my choice. I WANTED manual control of the transmission. For all of the 5 speed guys that " just had to have something to do with their right hand while driving" I didn't just want to put the thing in "D" and let the ECU tell it what to do either.....but you'll have to make that choice. If you choose manual, I've gotta 200.00 shifter with a shortened handle and leather knob waiting to go in a box that's yours for the asking.
 
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Lets say i am planning on having an ECU control the Transmission, do i still need the valve body? you will have to excuse me I really do know nothing about transmissions.
Nothing will have to be changed in the valve body then..you'll let the PNP control it through canbus. The weak part I'm told w/the trans is the stock input shaft. Evidently there is too much of an oiling relief cut into the shaft and it makes it prone to failure. I bought all of my junk from PATC, including that replacement.
 
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Thanks Mike, I will start looking into it. Without replacing the VB can i still use a ratchet shifter or am I confined to the hell of a standard D shifter.... I do have plans on utilizing paddle shifters of some sort, and a "sport mode" to increase shift firmness.
 
You'll probably have to leave the factory gear indicator module in place, and that will negate the possibility of using the aftermarket shifter ( requires the replacement of the gear selector shaft )
I don't know that for sure though..I sure would like it if I coulda kept that thing in place as that would've solved my gear indication light dilemma.
 
If you use the microsquirt as a TCU you dont have to change anything on the transmission as it will control all the functions. You will just connect the microsquirt to your ECU through CANBUS as you already know. These transmissions for the factory are rated to handle about 450-500 in stock form. I do highly recommend Mike's input in rebuilding it with the good clutches, OD band, and 300M hardened stubbed input shaft.

There is a lot of info on this for the TCU here:
http://www.msextra.com/forums/viewforum.php?f=138

Also this will give you an idea of the items that need to be replaced during the rebuild for the HP rating you are looking for:
http://www.silverfoxtrans.com/kits.html#kitaode700

Lastly, I have a copy of the rebuild process and items to enhance the transmission for TCCoA:
https://www.tccoa.com/articles/tranny/transmission/index.shtml
 

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Also I forgot to mention that you want to get the transmission from the newest model possible to get all the upgraded internals and servos. Look for only out of a 3.6L mustang from a 03-04. They didnt have enough power to do damage to the transmission and is a good platform to start with.
 
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My transmission was from an 03 car. I regret pulling it apart, as it showed no evidence of needing it. The pan is the telltale as to whether or not that needs to be done. there is a giant magnet in the floor of the pan that is there to catch metal debris that comes off of the friction surfaces. If there is no sht on the magnet, the clutches and bands are still alive and well. I will say that you have to be cognizant of the bell housing differences, so that you don't pull a Nick and have the wrong transmission rebuilt.

I'm glad I knew you when though..
I'm glad I knew you before you decided to have half of your brain removed so that some droid could do your shifting for you.

These guys all squawk about how mindless an auto trans is compared to a manual...and that was in lieu of the fact that a C4 still requires the pilot to push the shifter handle forward twice through the course of a 1/4 mile drag race.

( cause they know that they can't out-row an auto trans in a drag race...why in the hell somebody wants their car to be slower than it can be is beyond me)

But you won't even be doing that now will you? you'll put it in D, and mat the gas, and let your buddy HAL shift the thing for you...

"Dave,.....I do not think that that is the best course of action...........Dave?..........Are you listening to me?...,.,.,, Dave???
 
actually my plans involve utilizing the paddle shifter inputs on the TCU... I can either use actual paddles or lokar makes a shifter that has the side gated inputs that act as a slap shifter for up and down shifts. I like the paddles as an option personally.
 
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