98 Cobra 4R70w swap questions

[drhill]

I just realized I posted this in the wrong sub forum before....

Hi Everyone,

I just picked up a pretty respectable 1998 Cobra putting out between 750 and 850 rwhp depending on the tune and I want to put in a 4R70W to make it a bit less of a handful to drive. Right now it's a T56 with a real stiff SPEC clutch. I've already spoken with Freddy Brown about building one but I wanted to confirm the other parts I'll need to get it done.

4R70W transmission with manual valve body
dipstick and tube (I have long tubes - any issues with clearance here?)
flexplate
converter
stock shifter and cable or aftermarket ratchet shifter (how hard is it to mount these?)
crossmember (does the one from stiffler's work for this application?)
driveshaft ( I hear one from a 4R70W mustang GT will work - but I assume I should have one made because of my HP level - any recommendations?)
any electronics to hook up for speed sensor etc?

Am I missing anything?

Thanks in advance!!

 

[PACIFICGREENSVT]

Tip#1 Save some time and make sure the 4r70w is from a mustang.
If its not a mustang trans the geometry on the gear selector lever will be wrong!

Tip#2 Get the correct shifter cable for a mustang with a 4r70w and make sure the retainer clip comes with it/on it, you CAN NOT buy the clip from Ford any longer.

Tip#3 The 4r70w driveshaft yoke will fit right on your sn95/t45 Cobra driveshaft.So you can use your old driveshaft after you swap out yokes.

Tip#4 Spend the money on a good torque converter! DO NOT let people talk you into a high stall, you just don't need a super high stall unless its a drag only car.

Tip#5 You will need to move the trans crossmember up on the frame rails, the t45 trans mount will fit, its the same as the 4r70w trans mount.

Tip#6 An auto H pipe/X pipe/or custom mid pipe is needed!

Tip#7 the speed sensor from the t45 will fit right in the 4r70w.

 

[drhill]

Tip#1 Save some time and make sure the 4r70w is from a mustang.
If its not a mustang trans the geometry on the gear selector lever will be wrong!

Tip#2 Get the correct shifter cable for a mustang with a 4r70w and make sure the retainer clip comes with it/on it, you CAN NOT buy the clip from Ford any longer.

Tip#3 The 4r70w driveshaft yoke will fit right on your sn95/t45 Cobra driveshaft.So you can use your old driveshaft after you swap out yokes.

Tip#4 Spend the money on a good torque converter! DO NOT let people talk you into a high stall, you just don't need a super high stall unless its a drag only car.

Tip#5 You will need to move the trans crossmember up on the frame rails, the t45 trans mount will fit, its the same as the 4r70w trans mount.

Tip#6 An auto H pipe/X pipe/or custom mid pipe is needed!

Tip#7 the speed sensor from the t45 will fit right in the 4r70w.

Awesome! Thanks for the tips! when it comes to wiring for the reverse lights, neutral safety etc - does anyone have a wiring diagram for the 4r70w plug vs the t45 or t56 cobra transmission wiring harness? It would be helpful to know which wires do what so I can splice them together!

Thanks again!

 

[PACIFICGREENSVT]

What ever shifter you go with should have provisions for a neutral switch & rev lights. You just extend the wire up from the clutch pedal switch to the new shifter. I cant remember how I did the rev lights it was a few years ago, but it was pretty straight forward also.