347/C4 Combo into a 88 LX

June 21, 2006, 11:29:43 PM

Hey guys I was wondering how many people have put C4's into their birds. I have an engine and tranny combo and would like the keep them together if possible. The AOD I have is blown and am going to just rebuild the C4 with a full reverse manual valve body, with all the stronger parts and pieces as well. To those that have done it, what all has to be changed? Assumed driveshaft, and mounts, as well as linkages. Just trying to gauge where I am at, as I havent started to tear the bird apart yet.
Thanks,
-Matt

347/C4 Combo into a 88 LX

Reply #1 – June 22, 2006, 04:39:40 AM

"AOD/C3/C5 to C4/C6
The C4 has long been known as the drag racer's special. This bulletproof 3-speed transmission really wakes up the powerband in your Cat's motor in the quarter mile. For the 5.0, virtually nothing needs to be changed---the mounting pattern is the same (provided the bellhousing is set up for a small block Ford motor). You will need to shorten the driveshaft with this swap. The transmission crossmember must be changed to accommodate your new C4, using FRPP's C4 crossmember (p/n M-5059-A). You will also need to buy a new flexplate from FRPP, p/n M-6375-E302 (157-tooth, 50-oz imbalance, for all 1981-up 5.0 V8's). Since the C4 was found in some early-80's Fox cars, it's a nice fit. If you don't really need an overdrive for your car then this is the transmission to get. (Thanks to Royce for the part numbers above).

The C6 is also a very dependable transmission. But keep in mind that the C6 is physically a very big transmission and some tunnel "modification" (a.k.a. the BIG hammer) is needed to get it to fit. It is reported that the driver's footwell must be cut out for the linkage for the C6 to fit properly; a simple cover plate can be welded inside the car to cover the hole. Realistically, the C6 is best used for severe-torque motors (such as the Ford 460) and is a bit much for the daily commuter." coolcats.net

347/C4 Combo into a 88 LX

Reply #2 – June 22, 2006, 08:39:07 AM

Quote from: Haystack

You will also need to buy a new flexplate from FRPP, p/n M-6375-E302 (157-tooth, 50-oz imbalance, for all 1981-up 5.0 V8's).

That's not true for a 347 stroker...they use a 28oz imbalance.

347/C4 Combo into a 88 LX

Reply #3 – June 22, 2006, 11:38:37 AM

Thanks alot for the info.
-Matt