'68 Cougar upgrade to a 6 speed (6R80) Auto

[Gaugster]

I've made big plans for the Cougar this winter. The C6 three speed started slipping badly and I hear very good things about the 6R80. Long term plan is for my 390 engine to have a substantial power increase. Like 2X or 3X over stock. So beefing up the powertrain etc...makes a lot of sense. Here's some progress.

I have had to make clearance in the tunnel. No cutting yet but anticipate that I will need to make two small holes in the firewall so that I can torque the top transmission to block bolts. As some of you know I participate in the Classic Cougar forum. I have a post going over there too and will try to keep them both updated. This thread focused more on the FE whereas the Cougar forum gets more of the vehicle attention.

https://rumble.com/vbseqb-6r80-automatic-retrofit-1968-mercury-cougar-390-fe-big-block-p3.html

I am using the Speed Gems adaptor kit and so far the fit and finish have been great. The new starter has an integrated solenoid. I kept the original Ford solenoid mounted on the fender well. I'm not confident of the Cougar's 12V solenoid feed to have enough current to power the new solenoid+bendix. So I ran a dedicated 4 AWG battery cable to the starter and beefed up the ground return also. Now the original Ford solenoid output switches 12V to the new solenoid downstream. The new solenoid wire is 10 AWG. Overkill perhaps but it's what I had on hand. I will use a heat shield wrap over the starter. Doing everything I can think of to avoid the possibility of a heat-soaked starter lag issue.

The goal for today will be to confirm that starter works and can crank the engine. I have read about starters bending flex plates without the torque converter installed. So my plan is to bolt up the converter before putting any load on the flex plate.

[gregaba]

Good information. I used headers on mine and had more clearance then you have, I also used the fender mounted solenoid mainly because I am a old time mechanic and I like being able to hook up my remote starter switch instead of crawling under the car to hook it up to the solenoid.
Greg

[Gaugster]

Thanks. I have been reading the header posts in the Technical section. When under my car I was laughing at the thought of using a set in my Cougar with full shock towers. That's a problem for another day/year...

[Towd56]

What controller are you using with the 6r80?

[Gaugster]

What controller are you using with the 6r80?

I'm using the Quick 6 from US shift. Also got a Holley TPS kit to add to my Quick Fuel carburetor. The Holley and QF aren't exactly the same but I'm told it will work.

[Towd56]

What controller are you using with the 6r80?

I'm using the Quick 6 from US shift. Also got a Holley TPS kit to add to my Quick Fuel carburetor. The Holley and QF aren't exactly the same but I'm told it will work.

I just checked their website. Unbelievable what that controller can do.

[Rory428]

I am not an automatic guy, but thats quite interesting. What do you do for making the speedometer function? I imagine that you will need a driveshaft with a slip spline in the shaft. I have seen newer vehicle that some have that in the front section, others in the rear. Not sure if that matters one way of the other, just curious. Do these  have transmision dipsticks, or are they closed transmissions that require special procedures to check & add ATF to?

[e philpott]

Rory the ones I've seen have the a little dip stick right by the pan , no long tube anymore

Lockup is strong so you can program lockup at the end of each gear and it will feel like a 11 speed transmission with lockup in 2nd gear on up

[Gaugster]

I have done detailed research on most of the aspects of this swap. Plenty of things can go right or wrong but that's part of the fun.

A few companies make electrical input to cable output for driving mechanical speedometers. Dakota Digital has a device that I will probably use. Jegs and Summit list other options. I have a $700 budget for a custom aluminum driveshaft. But I hear rumors about some Ford's ('06 Explorers?) having an aluminum one. Most have the slip spline in the middle vs a slip yoke at the end. Guessing the lengths are some common denominator between the 2WD and 4WD systems. This and the trans mount are the biggest unknowns currently. Several companies make mounts into fox body and early model Mustangs. Will check if I can modify one somehow.
 
The 6R80 uses Mercron LV fluid which is intended for extended service intervals. As stated a mini dipstick with a specific checking procedure.

Lokar makes a sport shifter that is more hot rod style.

6 speeds with a lock up converter will make for a fun ride!

[Gaugster]

Test of the starter and wiring went well. Next step is to mount up the transmission, perform all the wiring of the new ECU and devise a mount for the tail shaft end.

https://rumble.com/vbupqp-6r80-automatic-retrofit-1968-mercury-cougar-390-fe-big-block-p4.html

[BigBlueIron]

I would love to do this swap one day. Thanks for the write up.

Is that cam plug in backwards??

[Gaugster]

I would love to do this swap one day. Thanks for the write up.

Is that cam plug in backwards??

Good catch on the cam plug. Yup. It's backward. Been that way for 20 years as far as I know. Hoping I can get another couple seasons out of the motor before I redo it.

I am excited to see how the 6R80 works. Still reshaping the tunnel to fit everything. Looks like I will only need one small additional hole in order to tighten the bellhousing bolts.

[BigBlueIron]

I figured it had been that way for quite some time, obviously it hasn't caused an issue.

[TomP]

I am curious why that adapter plate is that thick? It would seem like it could be half that thickness and at least give a chance to clear the firewall in most cars.
 I'm surprised the six speeds go for that much, there must be lots out there by now. There was a ten speed from a 2018 Mustang on local Craigslist for less than what some are asking for a 50,000 mile six speed.

[Gaugster]

I am curious why that adapter plate is that thick? It would seem like it could be half that thickness and at least give a chance to clear the firewall in most cars.
 I'm surprised the six speeds go for that much, there must be lots out there by now. There was a ten speed from a 2018 Mustang on local Craigslist for less than what some are asking for a 50,000 mile six speed.

At 1.5" it seems to be one of the thinner options. I think it was a comment on the Cougar forum but another kit for SBF was pushing 3". The crank adaptor itself is 1 inch thick. Add the new flywheel with enough room for a starter gear throw and your at 1.5" with ease.

They don't have an aftermarket controller for the 10 speed yet but I've read that it's in the works. Cost of the salvage  F-150 6r80 is anywhere from 300 to 1000 based on mileage. Double that if its from a Mustang but for no real reason.