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RustyNCa
06-27-2017, 10:10 PM
Does anyone know, can you run the flexplate from the Cruise-a-matic to the C6 converter. IE, can I just leave in the flexplate that I have in there, or do I have to change it out?

I'm already running a 390 with a later style starter, but I don't remember if I changed the flexplate back when I swapped out the motor.

Cheers and thanks for any help.
RustyNCA

http://i103.photobucket.com/albums/m125/justacog/58TBird/th_20170520_150303_zpsibstxy91.jpg (http://s103.photobucket.com/user/justacog/media/58TBird/20170520_150303_zpsibstxy91.jpg.html)
http://i103.photobucket.com/albums/m125/justacog/58TBird/th_20170625_142203_zps2slbcbcc.jpg (http://s103.photobucket.com/user/justacog/media/58TBird/20170625_142203_zps2slbcbcc.jpg.html)

jopizz
06-27-2017, 11:52 PM
If you are using the later starter then you have to have the later flexplate. They are not interchangeable. It should work fine in the C6.

John

simplyconnected
06-28-2017, 12:51 AM
Does anyone know, can you run the flexplate from the Cruise-a-matic to the C6 converter. IE, can I just leave in the flexplate that I have in there, or do I have to change it out?

I'm already running a 390 with a later style starter, but I don't remember if I changed the flexplate back when I swapped out the motor...
I have to look at your question backwards to understand it. You're running a 390 w/late starter motor. Now, you want to know if a C-O-M will fit?

Flex plates and converters simply bolt together with four studs/nuts.

C6 comes with its own integral bell housing (with starter motor bolt holes in it). Depending on what size car the C6 came out of it could use either the 157 or 164 tooth flex plate. Squarebirds with a C-O-M used a flex plate with 153 teeth and 15"-diameter.

If you're not sure, do a 'mock-up'... Outside the car, mount the starter to the bell housing and mount the flex plate to the torque converter. Now slide the torque converter into the transmission's input spline and see if the starter teeth mesh. The difference is 1/2" in flex plate diameters.

You could also count the teeth on your flex plate. 153 teeth fits a C-O-M bell housing. - Dave

jopizz
06-28-2017, 01:26 AM
To use the later starter your flexplate has to have 184 teeth. Thunderbirds in 1965 and 1966 used the same flexplate whether they had a COM or a C6.

John

OUR5T8BIRD
06-28-2017, 08:52 AM
To use the later starter your flexplate has to have 184 teeth. Thunderbirds in 1965 and 1966 used the same flexplate whether they had a COM or a C6.

John

John, is there not a difference for '66 if it was a 428 having to do with balance weights on the flexplate ( or drilled weight balance holes ? .

jopizz
06-28-2017, 10:02 AM
John, is there not a difference for '66 if it was a 428 having to do with balance weights on the flexplate ( or drilled weight balance holes ? .

Yes, the 428 does use a different flexplate than a 390.

John

pbf777
06-28-2017, 12:08 PM
[QUOTE=RustyNCa]Does anyone know, can you run the flexplate from the Cruise-a-matic to the C6 converter. IE, can I just leave in the flexplate that I have in there, or do I have to change it out?


You will need to buy the correct flexplate for the C6 (1966 thru say 1970 car application & thru 1977 for light truck), as the converter offset (depth) for the earlier MX, FX and FMX family of transmissions (if this is what you are indicating you have with the description "Cruise-a-matic", as Ford applied this vocabulary to several different units over the decade) and C6's are different.

No ifs, ands, or buts! ;)

Scott.

RustyNCa
06-28-2017, 01:05 PM
I guess how I worded it was confusing, but I think I may understand your answers.

My 58 had, well still has, a 390 in it with a modern starter, but running the original transmission. That transmission and I think primarily the converter finally started giving up after all these years.

So I have pulled the trans and have a couple C6 transmissions, with converters and flywheels sitting in the corner. One C6 came with a Mercury 410 motor I have, the other is from a pickup truck.

I was just wondering if anyone knew if the flywheel I already have on the motor would work with the C6. If not, I do have the flywheels that came with each C6.

Thanks for the help.

RustyNCA

pbf777
06-28-2017, 02:07 PM
You will need to use a flexplate that is appropriate for the C6, but not the units for a 410 or 428 cu. in. engines as these carry counter weight not applicable to your 390 cu. in. engine.


Scott.

jopizz
06-28-2017, 08:29 PM
You will need to buy the correct flexplate for the C6 (1966 thru say 1970 car application & thru 1977 for light truck), as the converter offset (depth) for the earlier MX, FX and FMX family of transmissions (if this is what you are indicating you have with the description "Cruise-a-matic", as Ford applied this vocabulary to several different units over the decade) and C6's are different.

No ifs, ands, or buts! ;)

Scott.

If that's the case then how come the flexplate you mention has a 1965 part number (C5AZ6375D). Ford didn't use the C6 until 1966. They were still using the COM in 1965. Just asking.

John

pbf777
06-29-2017, 01:23 PM
Nope!, can't explain it, wasn't there.;) But, with the same logic, why a C5# if for the C.O.M., (vs. say a B8 or B9#) since the C.O.M. appeared in the late 50's? Also consider that component assemblies which appear this model year where in engineering the year before (or more).

But, you may be correct, in that I believe the C.O.M. was produced only in 1965(?), with the new starter arrangements before being replaced by the C6 (in automotive applications). So, did the C6 use the C.O.M. flexplate; or perhaps the C6 was not ready for production, as intended, so the C.O.M. got the C6 flexplate (to use the newer starter) for one more year? And what other engineering considerations may have been made to make such happen? I don't know?

But, I have been informed by several transmission suppliers and torque convertor producers, over the years, that the C6 has it's own "converter-depth" dimension not shared with other units. And perhaps, even this statement may have simply over looked the 1965 only C.O.M.? Very possible. Note that this dimension is not overly critical, so even testimony of what someone else "got-away-with" does not pass muster.

One (RustyNCA) can establish with a somewhat accurate comparison (measurements) of the unknown unit (not original for the '58) from the vehicle to the known C6 units present for compatibility also.

So since we (I :D) seem to be left with doubt as to the appropriate use of an existing unit, from another application, and a minor variation could lead to catastrophic failure; and since the appropriate unit is readily available (even perhaps at hand, and maybe the existing ring gear teeth only appear so-so anyway), they're not expensive ($60.00 +/-, oriental imports:rolleyes: $30.00+/-), this leads me to advise......swap it!

Someone (please! :D) with the original Ford parts books, of the period (don't completely trust aftermarket listings) look up the C5AZ-6375-D unit; is it correct for the 1965 w/ the C.O.M. transmission (note that"Cruise-O-Matic" term was used in some literature to describe the C6 also!).

Scott.

jopizz
06-29-2017, 01:37 PM
The information I got is direct from the 65-72 Ford MPC. Ford went to the 184 tooth flexplate as well as the later starter in 1965 replacing the 153 tooth flexplate and starter with bendix that was used until 1964.

John

simplyconnected
06-30-2017, 12:09 AM
Does anyone know, can you run the flexplate from the Cruise-a-matic to the C6 converter. IE, can I just leave in the flexplate that I have in there, or do I have to change it out?

I'm already running a 390 with a later style starter, but I don't remember if I changed the flexplate back when I swapped out the motor.The C6 came with many bellhousing mounts because it was used in many engine/trans combinations. The integral bellhousing is the reason why the buyer must be sure of which engine family HIS C6 fits.

Do you happen to know what year engine your C6 came out of?
Do you know what model it was in?.. a truck (or Lincoln or Mercury)? C6 was also popular with SBF 351W engines as well. - Dave

pbf777
06-30-2017, 12:44 PM
John, thank you for supplying the application listing.

But, being the doubting thomas that I am (I have been lead to water............, more than once :o) and I believe, I mentioned in a previous post concerning inaccuracies that will be experienced in some literature (not implying that that with which you provided is such), and being a transitional period for the transmission units, with the compounding issue of Ford using the same terminology ("Cruise-A-Matic") for both, I wish I were left with no doubt, but...... :confused:?

Getting back to the original question, the title inquires: FMX to C6? No! The flexplate from the FMX does not interchange with the unit for the C6, if only for the reason of offset;).


The Ford C6 main housing was available with bellhousing configurations to fit: FE, MEL, 385 (also 6.9/7.3? D's), and 335 (later adopted for SBF in light truck) series engines for automotive (car) applications (did I miss one?:confused:). To the best of my experience/knowledge, year makes no difference for proper fitment, within the appropriate engine series of course.

There were however many different chassis applications (within each engine series) which incurred a multitude of other component differences, for example: flexplates, torque converters, oil pans, tail shafts & housings, flanges & yolks, internal components such as: clutches, plates, drums, bands, levers, servos, planetaries and valve body modifications, etc.,etc.

Scott.

jopizz
06-30-2017, 01:03 PM
I've checked multiple parts books and they all show the same part number for the 390 and 360 engines from 65-71 in cars and up to 1976 in trucks. From my personal experience the flexplate from a 1965 Thunderbird COM fits a 1966 Thunderbird C6. I can only go by what I know, not what someone else has said. Seeing is believing in my case.

John

RustyNCa
06-30-2017, 01:29 PM
The C6 came with many bellhousing mounts because it was used in many engine/trans combinations. The integral bellhousing is the reason why the buyer must be sure of which engine family HIS C6 fits.

Do you happen to know what year engine your C6 came out of?
Do you know what model it was in?.. a truck (or Lincoln or Mercury)? C6 was also popular with SBF 351W engines as well. - Dave

One came with a Mercury 410 motor, the other was a 71 or 72 truck if I remember right.

Here is some info on the 2 I have. They are thumbnails that will take you to a larger photo.

Cheers
RustyNCA

http://i103.photobucket.com/albums/m125/justacog/58TBird/Transmission/th_20170526_185531_zpsswd2yynd.jpg (http://s103.photobucket.com/user/justacog/media/58TBird/Transmission/20170526_185531_zpsswd2yynd.jpg.html)
http://i103.photobucket.com/albums/m125/justacog/58TBird/Transmission/th_20170526_184815_zpsxth3otxq.jpg (http://s103.photobucket.com/user/justacog/media/58TBird/Transmission/20170526_184815_zpsxth3otxq.jpg.html)
http://i103.photobucket.com/albums/m125/justacog/58TBird/Transmission/th_20170526_184610_zps1lo1jh6y.jpg (http://s103.photobucket.com/user/justacog/media/58TBird/Transmission/20170526_184610_zps1lo1jh6y.jpg.html)

jopizz
06-30-2017, 01:44 PM
Can you get the part numbers off of the flexplates you have. That should help us identify them.

John

pbf777
07-01-2017, 04:54 PM
[QUOTE=RustyNCa]One came with a Mercury 410 motor, the other was a 71 or 72 truck if I remember right.

The Mercury 410 (FE) would probably more closely replicate a "proper" unit for your car, with closer, but not correct, casting numbers and date codes (1968+/- vs 1970's) and automotive car application calibrations, and maybe even (but probably not) usable levers.

Make sure the truck unit (for an FE I assume) has an applicable tail shaft & housing for car vs. one unique to a truck, as this may be the deciding factor in the question, "which one do I use"? Many truck application units use a shorter main/output shaft with a bolt-on flange (vs. slip-yoke), and accompanying cast iron tail shaft housing, not suitable for your car.

The levers interchange from one unit to another (C6's) so no problem there, as long as you have one, of the many variations, which will work for your application.

The potential advantage to the truck unit may be superior internals. Back in the day, we would search for the C6's from the trucks, particularly the "Camper-Specials" as these proved to contain the better internals, which can be swapped into any other C6. For example, the four-pinion planetaries (vs. three-pinion), four-plate drum (vs.three), (which could be increased by one plate swapping retaining plate), higher leverage band lever, maybe higher rate 2nd gear servo, and............etc. Keep in mind, all these "superior" items may not lead to as smooth in operation a transmission.

Scott.

RustyNCa
07-03-2017, 02:47 PM
Can you get the part numbers off of the flexplates you have. That should help us identify them.

John

I looked at the two flywheels I have, the 410 one did have numbers on the balancing weight (so it is externally balanced?) and I am sure not correct to use with my 390. The other I never found any part numbers on it, but it seems identical to the one already mounted to my motor.

Both C6s seem to have the same tail section on them. The 390 one came with the slip yoke into the trans. It appears to fit the 410 trans, and the 58s original COM I pulled.

I ran into my buddy that gave me the Mercury 410 and asked him if he knew what it came from, he told me a 67 Mercury. But he didn't tell me what model. It's shift linkage is vastly different than the 58s, so that will take some work, or the other C6 linkage is closer to what I had.

The mercury trans does have some interesting electrical switch over the shift linkage at the trans with a long lead. Perhaps that is the safety switch?

Thanks guys
RustyNCA

jopizz
07-03-2017, 02:55 PM
I would use either the flexplate you have on there now or the one off the truck. Whichever one has less wear. I would not use the weighted one . You will have to do some mods on the shift linkage and trans mount to use the C6. You are correct about the neutral switch being on the transmission. You can just remove it or leave it. Use the neutral switch that is on your steering column.

John