flywheel, 157-164t, starter, backplate?

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We have a 72 with a 302 engine. We are swapping out the FMX to a T5 (pray for us!) and I just compared the old flywheel to the new one in the kit. The new one is about 1" smaller in diameter and is listed as a 157 tooth version. I presume that means the old one is the 164 tooth. From what I can tell, that means we need a new backplate to fit between the transmission and engine. It seems, from research, we can still recycle the starter, but I want to be sure. I would hate to tear the teeth off of the new flywheel. None of the research I did so far was definitive on the starter, though I saw a mention of different starters for automatics and manuals.. There are 3/4" and 3/8" offset starters, but it isn't clear it that difference involves the flywheel change we will be making.

As an aside, I was really surprised at how much heavier the new flywheel is than the old one. It probably has to do with the old one having to carry a torque converter. This is the first time I have done this stuff on a car with an automatic, so there are a number things here that are new to me.

Thanks in advance.

 
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Have you been to the Modern Driveline website? https://www.moderndriveline.com/

They are a little disorganized, but there are a bunch of videos and tutorials on your exact project.  Probably able to answer most of your questions there.

I just did the FMX to T5 swap on my 351C.  I cheated and bought a complete kit from MDL.  You'll find some photos of my swap in the "What did you do to your car today" thread; July/August time frame.

The hardest part of the whole swap was pulling the pedal box and installing the clutch pedal.

 

Hemikiller

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Just to clear up the nomenclature - manual transmissions use a flywheel, automatics use a flexplate. 

The manual/automatic designation of starters is incorrect, as it *depends* on the flywheel size being used. This started over 50 years ago with aftermarket parts catalogs and has never been fixed. Ford exclusively used the 157th flywheel in the Mustang until 1968, then switched to the 164th flywheel with the new 302. Prior to that, it was a mix n match setup in the full size and Fairlanes depending upon how the car was optioned. 

164th flywheel manual transmissions use the short 3/8" offset "manual" starter. Lester interchange # is 3132

164th flexplate, 157th flexplate and 157th flywheel applications use the deep 3/4" offset "automatic" starter.  Lester interchange # is 3124

That said, you can use your existing starter as you are using a 157th flywheel. 

You will need a block plate that matches the 157th bell, as the starter location is closer to the crank centerline. 

https://www.neperformancemustang.com/catalog/product_info.php?products_id=283

startersidebyside.JPG

sbf starter.jpg

ford starters.pdf

 

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Have you been to the Modern Driveline website? https://www.moderndriveline.com/

They are a little disorganized, but there are a bunch of videos and tutorials on your exact project.  Probably able to answer most of your questions there.

I just did the FMX to T5 swap on my 351C.  I cheated and bought a complete kit from MDL.  You'll find some photos of my swap in the "What did you do to your car today" thread; July/August time frame.

The hardest part of the whole swap was pulling the pedal box and installing the clutch pedal.
If you have any tips on the clutch install, they would be welcome. I am dreading that, though am partly there as the brake booster and master were in need of service.

 
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If you have any tips on the clutch install, they would be welcome. I am dreading that, though am partly there as the brake booster and master were in need of service.
As you know you need to get the pedal box out of the car so you can fit the clutch pedal.

Pull the driver seat if you haven't already as you'll definitely need the room to get in there.  You will need to drop the steering column.  I did not remove it completely, I just disconnected the rag joint, dropped the column and shoved it toward the console.

I took the opportunity to replace the rag joint while I was at it.  You might also cut the automatic transmission shift lock tab off the steering shaft as you are not going to need it and it will give you a bit more room.

Don't worry, putting it back together is easier than taking it apart.

A couple of Advil pills 30 minutes before contorting under the dash seemed to help as well.

Good luck!

 

midlife

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Just to clear up the nomenclature - manual transmissions use a flywheel, automatics use a flexplate. 

The manual/automatic designation of starters is incorrect, as it *depends* on the flywheel size being used. This started over 50 years ago with aftermarket parts catalogs and has never been fixed. Ford exclusively used the 157th flywheel in the Mustang until 1968, then switched to the 164th flywheel with the new 302. Prior to that, it was a mix n match setup in the full size and Fairlanes depending upon how the car was optioned. 

164th flywheel manual transmissions use the short 3/8" offset "manual" starter. Lester interchange # is 3132

164th flexplate, 157th flexplate and 157th flywheel applications use the deep 3/4" offset "automatic" starter.  Lester interchange # is 3124

That said, you can use your existing starter as you are using a 157th flywheel. 

You will need a block plate that matches the 157th bell, as the starter location is closer to the crank centerline. 

https://www.neperformancemustang.com/catalog/product_info.php?products_id=283

View attachment 56420

View attachment 56421

ford starters.pdf 897.22 kB · 2 downloads
Oh yeah, right on!  I had to replace Midlife's (1966 289 4 speed) starter, and got the 164 tooth version, and for the life of me, I could not fit it into the starter hole.  I brought it back, and the parts folks laughed at me, as this is a very simple job.  They had already turned in my core, so I simply got my money back.  I then went to a place that specialized in starters and alternators, and explained the problem I had.  They scratched their heads and said, here, take this automatic version.  If it doesn't work, bring it back and we'll try something else.  Well, what do you know?  It worked like a charm.  Almost all the catalogs have the applications wrong.

Thank you, Hemikiller, for setting things straight (once again)!

 
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As you know you need to get the pedal box out of the car so you can fit the clutch pedal.

Pull the driver seat if you haven't already as you'll definitely need the room to get in there.  You will need to drop the steering column.  I did not remove it completely, I just disconnected the rag joint, dropped the column and shoved it toward the console.

I took the opportunity to replace the rag joint while I was at it.  You might also cut the automatic transmission shift lock tab off the steering shaft as you are not going to need it and it will give you a bit more room.

Don't worry, putting it back together is easier than taking it apart.

A couple of Advil pills 30 minutes before contorting under the dash seemed to help as well.

Good luck!
Thanks! We are also swapping out the power steering, so the column has to come out too. Sigh. Seat is out since I wanted my son to have something with a headrest. Whiplash really bites. I will probably need a bottle of Advil.

 
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Oh yeah, right on!  I had to replace Midlife's (1966 289 4 speed) starter, and got the 164 tooth version, and for the life of me, I could not fit it into the starter hole.  I brought it back, and the parts folks laughed at me, as this is a very simple job.  They had already turned in my core, so I simply got my money back.  I then went to a place that specialized in starters and alternators, and explained the problem I had.  They scratched their heads and said, here, take this automatic version.  If it doesn't work, bring it back and we'll try something else.  Well, what do you know?  It worked like a charm.  Almost all the catalogs have the applications wrong.

Thank you, Hemikiller, for setting things straight (once again)!
Thanks both of you. Besides the parts catalogs being wrong, there is always the question about whether the last guy to do a job did it correctly with the right parts. I am wondering about that on the drum brake springs as none of the kits exactly match what I found on the car. Then there is the joy of Ford manuals that show a generic item from a 72 Ford and not the specific one for the Mustang. The springs are color coded, but never found anything that explained what colors I need. Argh. 

 

droptop73

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I converted mine from a C6 to 5 speed about 10 years ago using a mad mish mash of parts, most were modified and some custom fabbed. I used a small permanent magnet starter intended for a late 90s manual transmission Ford van. As I recall I needed to open up the hole slightly but the starter worked great. 

 
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