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What auto trans for 69 351W?

DEL65

DEL65

Of The Morons
My friend has an original unrestored 69 Mach, factory 4v 351W / FMX trans. He is planning to rebuild the engine and beef it up. He is looking for a durable auto trans, and heard that a rebuilt C6 will be stronger and a better value than a FMX. But in order to fit the 351 block, the C6 must have a small (rare?) bell housing.

Now it is my understanding that a C6 is unnecessary and a property built C4 can handle a modded street 351W. Additionally, the C4 is smaller, lighter, and has less moving mass

Is this info accurate? What year/make/model C6 tans does he need to look for? Can a C6 bellhousing be swapped from a large to a small one? I'll probably have more questions and this goes on. Thanks.
 
Bell housings aren't swappable on C-6 transmissions, C-6's are also known as HP hogs. C-4 built would be a better choice. Has thought been put into a AOD or AODE?

From infinity and beyond
 
"Grabber70Mach" said:
Bell housings aren't swappable on C-6 transmissions, C-6's are also known as HP hogs. C-4 built would be a better choice. Has thought been put into a AOD or AODE?

From infinity and beyond
Click to expand...

Same thinking here.

When he uses the mach for regular roadtrips , he can benefit from the overdrive which the AOD has.
 
I agree that the best replacement would be an AOD and suggested the same to him. But, he's set on a regular 3 speed. Thanks.
 
C-4 would be fine for his street application. They can be built plenty stout, and in fact someone out there makes a bell housing to put it behind an FE.

The AOD is based on the FMX architecture - AOD would be an easy swap. In this day and age, I would not pay to rebuild a C4 unless originality was your primary motive. Same goes for C6. The cars just drive so much nicer with OD. And get better MPG if you care about that.
 
"Grabber70Mach" said:
Bell housings aren't swappable on C-6 transmissions, C-6's are also known as HP hogs. C-4 built would be a better choice. Has thought been put into a AOD or AODE?

From infinity and beyond
Click to expand...
Ford made C6's that will bolt to the Windsor engines. I had one in my first 67 that I took out of a van. I have a Motor home with a 351W and a C6
I love my C6
10421294_10202492328455071_9056695925383643079_n.jpg
 
I really like the 351W/C4 combo in my Mach I...it's my favorite automatic tranny. I would happily replace any FMX with a C4 any day of the week. Some guy on eBay actually makes kick-down rods for this comb even.
 
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