C4 to manual swap

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Cribbs74

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Hey guys, new here. Just picked up a ‘72 coupe. I do not do automatics in anything I drive so I am wanting to get rid of the C4. I have done an auto to manual swap on my ‘72 Dodge pickup, so not a stranger to the required work.

I have read a few articles and even a few threads here about swaps, I am wanting to do something with all Ford parts to get around fabrication and modifications.

I would like to use a T-5 and possibly make it all work using factory clutch parts/linkage,bell housing and flywheel.
 

Is this a pipe dream? 2V302 for reference. Thanks for any help or information you can provide.

Ron

 
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I've done several auto to manual swaps in 71-73 cars. Quite doable and a very satisfying change in the car. The T-5 is a good match, as you can use the complete factory setup with an adapter plate. You will need to be careful which T5 you get, as there are a zillion different models with various torque capacities and  input shaft lengths. 

71-73clutch.jpg

 
Thank you for the picture, seems like I have a lot of sourcing to do. It would be nice if I had a donor vehicle to get everything I need in one place. 
 

 
Thank you for the picture, seems like I have a lot of sourcing to do. It would be nice if I had a donor vehicle to get everything I need in one place. 
 
Much of the required parts are available new. The Z-bar assembly, the clutch pedal, all the return springs and some other stuff. You can search on NPD's site using the basic part number shown in the pic. The problem with much of the used linkage out there is it needs to be welded and remachined due to excessive wear. 

The clutch fork is not made, nor is the overcenter spring bracket (7523). You can get a Scott Drake roller clutch bearing kit and weld it into your existing pedal hanger. Re-use your existing brake pedal, just cut the pad down to match the manual trans brake pedal pad width. 

https://www.npdlink.com/product/bar-assy-clutch-equalizer-repro-incl-frame-mount/206414?backurl=search%2Fproducts%3Fsearch_terms%3D7528%26top_parent%3D200001%26year%3D1971&year=1971

https://www.npdlink.com/product/rod-clutch-release-lever-upper/144856?backurl=search%2Fproducts%3Fsearch_terms%3D7521%26top_parent%3D200001%26year%3D1973&year=1973

https://www.npdlink.com/product/pivot-bracket-clutch-equalizer/146200?backurl=search%2Fproducts%3Fsearch_terms%3D7a572%26top_parent%3D200001%26year%3D1973&year=1973

 
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Modern Driveline has a lot of info on their site. I ended up buying the whole conversion kit and a TKO600 from them but they have everything for T-5s as well. Might be a good idea to get an itemized quote on the whole kit from them for a T-5. Then you can always do a price analysis and figure out which parts you want to buy new vs source from donor cars.
 

Definitely research which T-5 you want to get. I don’t know much about them but there are big differences across the different versions. Going entirely on memory from a friend’s experience, I think you want a later model World Class...but I seem to remember that very late models don’t work easily for some reason in our application (gauges maybe?)

I remember seeing some very informative articles about it in Mustang Monthly (that’s where I found out about Modern Driveline).  Here is one I found when I did a quick search for you. 
 

http://www.mustangandfords.com/how-to/drivetrain/1408-simple-five-speed-swap-for-your-1971-1973-mustang/

 
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Thanks everyone, car is home and we are going through it. Lots of work to be done, but it will be worth it. I appreciate the links and time taken to reply.

Ron

 
Cribbs 74,

If you choose to install a T5, or any Tremec for that matter, make sure you dial indicate the the centerline of the crankshaft to the bell housing opening.

I BELIEVE the spec is 0.005'' because the Tremecs use a tapered mainshaft front bearing.

Clean both the engine to bell flange and bell housing flange, you need do do both radial and axial runout (do radial first), i used shim stock between the engine block and bell housing to dial it in, and you MAY need offset dowel pins to get the AXIAL runout within specifications.

If you are using a adapter plate, take your readings off of the adapter plate, not the bell opening.

If you get this wrong, plan on replacing your front mainshaft bearing.

Boilermaster

 
I had been on the look out for a T-5 to put in a track days car I want to build. I lucked out and 20 min. after he posted it on Facebook market place I scored a 1995 T-5 out of a GT. He had just put a new clutch in and took to the drag strip. Was tired and decided to drive home on the slicks and hit a wet spot in road and totaled the car. I got the bell housing, flywheel, clutch, pressure plate, throw out bearing and transmission for $350 and he delivered it to me because of my bad disc. Since I am going to a Cleveland the flywheel will not work for me but everything else should.
Like someone stated there are a bunch of them out there the WC did not start until I think the SVO. They used different steel in the gears and different synchronizers. 1995 is last year for the 302, 1996 went to modular. There are 4 cylinder and 6 cylinder models so be sure you know what you are buying.
If you went with a Toploader you need to find a donor car and get everything at one time or you will be looking for missing pieces for a while. If you buy from somebody else for Toploader expect to pay $2,000 for everything from rear yoke to the crankshaft.
Another big factor is PDB or not the pedal assembly is different and hole in the firewall also. Do research on the net some good videos out there also. Here is picture of the tag on the one I got for reference. It has the good gears and syncro and is last year and out of a GT.
Remember torque does not break transmission sticky wide tires do. lol.

20210223_153140.jpg

 
I did some poking around under the grande parts car and looked at the tag on the Tremec T-5

The number on the tag is 1352-249.
From my research it’s a close ratio trans with a .63 overdrive. While I am happy with the ratios I don’t know how a .63 with a 3.00:1 axle ratio is going to do behind a stock 302. only mod is a 4bbl carb. Plus I have 15” Magnum 500’s going on in place of the 14’s which will knock the rear end down even further. I imagine a lot of downshifting on hills in my sons future. I think a 3:73 change should be on the list.
 
That seems to be a Ford Motorsports WC T-5, my understanding is that the 1352-249 was only available through the Ford Motorsports parts counter. You got the best of the best when it comes to T-5's there. I would definitely use gearing between 3.55 and 4.10, 3.73 is a good compromise. Please remember that 5.0 Mustangs used the T5 transmission from the factory with 2.73 rear gears (3.08 were the optional performance gear set) with a .68 final drive. So, you can definitely use 3.00 gears with the .63. You will still get decent acceleration with the 3.00 gears as the first gear on the transmission is 2.95. You could just try it out and see how you like it, worse comes to worse do a gear swap.
 
Just a bit of a follow up. My son and I are finally driving this car. 1-4th gear it does ok, but 5th is a straight dog. Anything under 70mph and It is gutless. I installed a 3:40 which I assume is out of a MustangII it was $50 so I figured why not. It certainly did’t help much. so now I am at a place where cruising along at 55 in 4th seems buzzy and undriveable when I shift into 5th.

I am wondering if the engine itself doesn’t have enough torque. I have no idea what’s going on inside that engine, but I assume it’s just a stock replacement 302. It pulls well enough in the lower gears, not a screamer by any definition but adequate.

Looks like I have more work to do!

Ron
 
A 3.40 with the .63 overdrive nets you a 2.14:1 rear, which is way too low. I ran a 3.40 with my 302/Toploader combo and it was fine on the highway with 26" tires. If you switch to a clutch fan it'll cut down on a lot of the noise and buzziness at higher RPMs.
 
Just a bit of a follow up. My son and I are finally driving this car. 1-4th gear it does ok, but 5th is a straight dog. Anything under 70mph and It is gutless. I installed a 3:40 which I assume is out of a MustangII it was $50 so I figured why not. It certainly did’t help much. so now I am at a place where cruising along at 55 in 4th seems buzzy and undriveable when I shift into 5th.

I am wondering if the engine itself doesn’t have enough torque. I have no idea what’s going on inside that engine, but I assume it’s just a stock replacement 302. It pulls well enough in the lower gears, not a screamer by any definition but adequate.

Looks like I have more work to do!

Ron
You need to consider all the gear radios from 1st to 5th, your rear end ratio, your tire size, and where you want your engine to be. Modern driveline has a handy calculator app where you can plug in different parameters. With that rear end and overdrive ratio, the tire size pretty much doesnt matter in the equation. It only shifts your speed around like 3-4mph.

With a 26" tall tire, 3.4:1 rear end, 0.63 overdrive. 55mph is 2400 rpm in 4th gear, 1510 rpm in 5th gear. Then 2000 rpm is 72mph. You break 100mph before you hit 3000 rpm.
 
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