351c bolt to T5?

I have a 4spd Cougar and would like to get better freeway gears. I would like to know if a 351c and a T5 bolt up together? Or can I change differential gears and keep the 4spd what is my best option?

Many Ford engines including the 289 (6 bolt), 302, 351W and 351C share the same bellhousing bolt pattern. The T5 comes in many configurations including Chevrolet, Pontiac, Buick, Ford etc. If you choose the correct Ford T5 and have a 351C with the same bolt pattern yes they bolt up. You still need to source an appropriate throwout bearing, clutch etc.

T5’s come in various torque ratings so you need to choose one that is capable of using what your engine produces.

I put a T-5z behind my 351c and switched the rear end to 3.50 and couldn’t be happier. As Royce said, be sure to get one that’s stout enough for your engine. My mostly stock 351c is no problem for the T-5z but some of the older T-5 units had limitations.

This…but I’m happier than bmwhd1. :smiley: Be sure to check the drive shaft length. When mine was installed, that didn’t happen and I gave it some load one afternoon, and it sheared my u-joint right off. Mine took about a 1-1/2" shave. My Cleveland has some performance mods, but the T-5z has no problem with it. If you do like we did, and go to 3.50 posi, you’ll need a new speedo gear too.

Also - as important as driveshaft length is a concept I’d never heard of called bell housing run out. The T-5 (and maybe others) are really sensitive to misalignment with the engine crankshaft. Why you’d design something to 0.005" tolerance that wasn’t designed to go into space is beyond me.

This company basically pioneered the T5 conversions for Ford and Mustang.
https://www.moderndriveline.com/

Hunt around on the site. There should be a T5 numbers breakdown for applications. Fox body Mustangs 1989-93? I think are the strongest with 5.0 V-8.
If you do a search of “vintage Mustang 5 speed conversion” you should find a bunch of information.

I did a T-5Z swap in to my 70 XR-7. It is a 351W., but the fit is the same. The T-5Z is the strongest of the Ford T-5 line. My kit was from Modern Driveline out of Idaho. The company CougarCJ mentioned. I swapped the gears for a set of 3.50 with a Tru-Trac unit and love it.
I documented in this thread, https://cccforum.discoursehosting.net/t/so-i-am-planning-to-repower-ginger-this-winter-spring/4248/1

You can use your stock clutch linkage and bell housing, but you need a spacer plate to used the T-5.
I used the Fox body Mustang bell housing and clutch which uses a cable.
If I had it to do over again, I would strongly look at the hydraulic clutch. Next time.

Thank you very much to all the people on here for your help its very much appreciated.

While this is a possibility I would recommend going with a hydraulic or cable clutch setup to avoid the use of the Z-bar setup and that’s easier with the T5 bellhousing.

I am using a TKO600 not the T5 with my Cleveland. I also switched to a Fox body aluminum bellhousing to convert to hydraulic clutch with master and slave cylinders instead of the stock Z bar which interfered with my rack and pinion steering and headers. I have the T5 spacer and a California Pony cars crossmember for sale if you’re interested. As noted above, these allow you to mount the T5 to your bell housing and to the car.