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FMX to 4r70w swap
Just completed the tranny swap from an FMX to a year 2000 4r70w and high stall converter. I used a manual shift valve body and a racing converter sourced from the clickclick racing forums. It can be also adapted with an electronic controler if you want to retain auto shifting. I didnt want to mess with the electronics and tuning so took the easier route.
The 4r is 1" longer so the mount is farther back, the unusual thing is I was able to modify my existing crossmember and a few other things to make it work. And look semi stock appearing, even reused the original shifter and linkage.
I have a souped up cleveland and 4.10 gears and I got tired of driving on the highway at 3500 rpms while the mini vans passed me. The overdrive and electric lock up are the reason I chose this tranny.
The other reason was to have a 4000 rpm stall converter and be able to lock it up via a switch for cruising eliminating the slippage and heat that comes with it.
Here are a few pictures
4r70w from 2000 v-6 mustang with 4k stall converter
[Image: 4r70wconversion009.jpg]
FMX is out
[Image: 4r70wconversion012.jpg]

Chopped forward ear and front section off, this weakens the x member, so I added gussets and boxed it in from underneath. also reinforced the factory welds which are spot welds.
[Image: 4r70wconversion014.jpg]
[Image: 4r70wconversion013.jpg]
[Image: 4r70wconversion016.jpg]
[Image: 4r70wconversion022.jpg]
[Image: 4r70wconversion023.jpg]
I slotted the holes as far as I could to allow more adjustability on the crossmember. Then I cut this bump off the rubber mount and flipped it which also gained some room then slotted the mount as well and used allen head bolts since the new holes are now close to the wall.
[Image: 4r70wconversion017.jpg]
Here it is installed showing the wires that shft OD and lock up, I installed the switches on the forward wall of the ashtray so when I close the lid the car looks stock.

[Image: 4r70wconversion027.jpg]
[Image: 4r70wconversion026.jpg]

I changed the rear yoke to a 1350 series I found at a junkyard because the 71-73 use a funky and small yoke, this gave me more driveshaft options as well as strength. The yoke was the same lenght as the original so I needed a 50" center to center driveshaft. I got lucky and found one at the junkyard that was 50 1/4" long.unfortunately I dont know what ford vehicle it came out offor reference, maybe a truck with a larger tranny.
Last night I was buttoning up the drive shaft and was so desperate to run it but my muffler was hitting the driveshaft and I lost my patience to get it running. So I need a new muffler now.
[Image: 4r70wconversion029.jpg]

I didnt like them anyways, so I will upgrade them soon.

I should probably make a list of parts needed for the swap and such before I forget
Very nice. O/D is on my wish list.

73 conv. 460, D0VE large valve heads, Performer RPM manifold, Voodoo 227/233 cam, Holley 950 HP carb, C6 trans, 3.25 trak-loc.
awesome swap, is there any difference in strength when it come to the 4r70ws? I know they were offered in trucks as well as mustangs, would the truck transmission be any stronger than the V6 mustangs?

72 Mach-1 12:1 532 Forged internal Scat stroker, Kaase P51 heads, Comp roller cam, March serpentine conversion, C6 manual VB, 9'' 4:33:1.
66 convertible 289, 82k miles.
I have read a 4.2L truck tranny has one extra clutch plate but the tranny may be longer overall. Also read that you can just add the extra clutch disc to the V-6 tranny.
The problem with the truck tranny is its hard to find one with low miles and an easy life, I found the V-6 tranny that had low miles and was spotless inside so I used it as is without rebuilding to save costs.

The years to get are 98-2002 just make sure they have a speedo spline on the tailshaft.

[Image: mustangnight010.jpg]
1972 Mustang Convertible 351C 4V
1966 Ford Galaxie 7 litre-4speed

very cool, im surprised that the 4R bolted up to the cleveland with out an adapter plate of some sort. Same bellhousing bolt pattern. If im not mistaken, the 351C and the 429 are the same bolt pattern for the bell housing. just wondering if the 4R would hold up behind my 532....

72 Mach-1 12:1 532 Forged internal Scat stroker, Kaase P51 heads, Comp roller cam, March serpentine conversion, C6 manual VB, 9'' 4:33:1.
66 convertible 289, 82k miles.
351 C is same as small blocks, it won't bolt up to the big blocks.
I did read that you can use an E40D truck tranny posibbly. I think it was 460ford.com
Yes, MACH1460 you were probably thinking of the 400 which has the same bolt pattern as the 429/460.

I don't know if the 4r70w (even with the modifications) will hold up to your Stroker big block, especially if you are getting into it.


Do the RIGHT thing.
So far my c6 is holding up, even with the slicks. Thing is a rocket with the slicks. It sure would be nice to have one more gear... Maybe someday.

72 Mach-1 12:1 532 Forged internal Scat stroker, Kaase P51 heads, Comp roller cam, March serpentine conversion, C6 manual VB, 9'' 4:33:1.
66 convertible 289, 82k miles.
what flexplate did you use? the cleveland is 28 oz.balance and correct me if im wrong were not the 4r70w's used with 50 oz flexplates?
so were you able to use the felxplate from the fmx (28 oz, ) or did you go aftermarket?
also isnt the dish on the two flexplates different, the fmx being more dished and the 4r70w more flat surface?
just asking what you did . thanks

in loving memory of my son ..Jason
The original 351C/FMX flexplate fits perfectly on the V6 4r70w converter.
Or you can purchase an aftermarket flex for your motor as long as it has the common 11 7/16" converter bolt circle
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