6R80 conversion in 2003 Mach1

[TTSaleen]

After a few years, I decided to give the 6R80 another try but this time in my 2003 Mach1. It makes about 1/2 the horsepower of my TTSaleen so I thought it might work better.

Overall view -
Built 4.6 with 2.3 VMP Supercharger
L+M cams
Stock computer on E85
Previously had T56 magnum and made 790rwhp and ran 10.18 @ 140mph in 1/4.

2024 build for 6R80 with current pricing:
This time I decided to do things more on a budget and not go "all-out".

2014 6R80 trans and converter out of 2014 Lincoln Navigator - Ebay $600
Dorman 946-374 driveshaft - O'reilly's $430
Stiffler's crossmember - $0 - had leftover from previous project
Flexplate - $0 - had leftover from previous project
Midplate - $0 - had leftover from previous project
Bellhousing bolts - W714012-S439 - $23 (2 packs of 4 each)
IRS flange adapter - Neapco N3-2-1579 Flange Yoke 1350 Series - $50
Quick6 Gen2 6R80 controller - $1,255
2004 auto shifter - $150
2004 shift cable - XR3Z-7E395-AA - $63
Dipstick - 22200 - $165
Trans cooler - Derale 15300 Tube and Fin Cooler -$89
8AN PTFE Line Kit - $92
New trans filter - FT-188 - $18
New trans pan gasket - FEL-PRO TOS 18753 - $24
12 Quarts Mercon LV fluid - $99

Initial impressions -
My car has the L+M cams and a noticeable idle. While this works great for a manual car, I had to increase the base idle speed to compensate when putting car in gear.
Before it would die/idle too low due to drag of 6R80.
My base idle is 1,100 rpm now and in gear it will hold idle at 850 rpm.
With the AC on, it will hold idle at 950 rpm.
Other than this little annoyance, it drive VERY well.

The new Gen2 controller is much improved over the older Gen1 I had used before.
So far no error codes, shifts exactly where I tell it, and runs great.
Having the digital interface is also nice for diagnostics and telling what gear it is in.

Problems so far -
I had to adjust the shift cable twice to get it to tell the controller it was in the correct position. Not a big deal.
The driveshaft is a 1 piece, but made of steel. I have a vibration around 35-45 mph and it is pretty bad. The shaft is only out 1.5" from fully collapsed (had 3.5" total of movement available), so not sure if it just needs balancing or something else is happening.
The 104,000 mile stock transmission is NOT happy with my approximately 900 flywheel horsepower!
The first few days it ran and shifted perfectly.
After I BEAT on it a few times, it now flares going into 4th gear.
Guess I should have done the clutch upgrade while I had it out. Oh well live an learn!

I will tell you the car feels ALOT faster now, but it is killing the tires with my 3.73 rear gears. I need to drop that down and thinking something like 3.15 or 3.27 due to the instant torque of my supercharger (23# boost).

I'm hoping to run high 9's when I go back to the track, but won't until the weather cools off and I get the clutches changed in it.

Here's 2 videos I did on it.
1st is the entire swap process.
2nd is the "torture" session on street tires.

 

[07GtS197]

That thing is nasty! I hope you get it all sorted out soon.

 

[lwarrior1016]

Some of your rpm drop issues might get better with a stall converter in it. I think I remember you saying you were using the stock navigator converter.

 

[TTSaleen]

Some of your rpm drop issues might get better with a stall converter in it. I think I remember you saying you were using the stock navigator converter.

I had thought that too years ago when I had this setup in my Mach1 and had a Circle D converter in it. It was built for my TTSaleen was a 3 disc lockup style with a 3,800 stall speed. However at idle it pulled the car down just like this stock converter is doing. When I asked Circle D, they said the 3 disc clutch versions can cause some drag at idle, no way around it.
This is why I had pulled it out and sold that kit years ago. Now with a stock converter it is basically doing the same thing.
After talking to my transmission guy, he said the 6R80 has a lot of drag at idle inherent to how it is built and higher rpms will compound that. Makes sense as to what my car is doing. If i could idle it around 800rpms, he said it probably wouldn't be as noticeable. Unfortunately with these cams, I can't do that and still keep it at an idle.

But I will say this stock converter stall (approx 1,800) works very well in the launch for my car. Just zero traction. LOL.

Ryan

 

[TTSaleen]

I have a 2003 Mach 1 ECU in my car that was factory manual transmission.
I just put a 6R80 transmission into it but the ECU doesn't know it is in gear and tries to stall out.

I think I need a way to get the transmission input into the ECU such as the Digital Transmission Range sensor input.
Would that be correct?

I have a US Shift controller so I have a way to identify when it is in gear.
I was told my tuner can reprogram my ECU from a manual to an auto and adjust the idle circuit.
However he told me I need a way to trigger it when in gear.

Any help or advice is much appreciated to get this project 100%.
Thank you,
Ryan

 

[lwarrior1016]

That’s going to be a tough one. I don’t think the manual computer can changed to auto, and the idle strategies are different between the two.

I also don’t know how the 4r70 range sensor sends its signal to the computer. I’d imagine you have to mimic that, but I don’t know if that’s possible on the 6r80.

How did you manage to get around it before?

 

[TTSaleen]

I never got around it previously. I simply raised the base idle to compensate.
It's a band-aid at best.
If I need to grab an auto computer (found one in a 2003 Mach1 wrecked) I can do that.
Just need to figure out how to take the Quick6 wiring for in gear and send that signal to the ECU.

Crazy no one else has done or posted about it (I've been looking).
Ryan

 

[lwarrior1016]

Yeah, I haven’t seen a whole lot about it either. I’ve seen a few folks that have used gen 1 coyote computers on the 4.6 so it will control the transmission like stock.

But that involves some wiring, and electronic throttle body and pedal. Tons of work.

 

[TTSaleen]

A guy on Modularfords told me he fixed it in his car by increasing timing at idle.

I gave it a little more timing advance in the cells just above where my idle MAP is. So now, instead of stalling, the ECU gives more timing and it returns right back where it was. No more stalling when cold.

I don't have access to that with my handheld, so I plan to see my tuner in a few weeks and see if he can play with that.
I'll definitely post the outcome and if that is a solution.
Ryan

 

[lwarrior1016]

That’s reasonable, and I hope that fixes it.

 

[TTSaleen]

Got the 6R80 pulled out yesterday. Kept getting failure codes for 4th gear and it would go into limp mode.
I pulled it out and drained fluid and it was dark/burnt.
Found a trick to remove it with the long tube headers - took 2 straps and pulled the header collectors toward outside of car. Made removing much easier.
Now to get it inspected and rebuilt with better parts.