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C4 or 3speed with efi..?

72-Madisyn

Full Member
Joined
Dec 21, 2007
Messages
211
Loc.
Medford
currently have stock 3 speed trans, am about to put in my efi motor and was wondering if it is better to run that trans and buy the flywheel/clutch kit to match it or should I just swap in a c4 that I have, or for that matter a c6 that I already have? Trying to do my motor swap with the lowest cost possible, kinda tight right now, so looking for my best option. what are c4-dana 20 adapters going for these days? daily driver/ weekend trail runs. sorry for the long post. going on this weekend so help would be great. thanks
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
35,265
Presuming that you are dropping in a complete late model engine...
As far as the trans goes there is no need to change to automatic right away.
Use the right flywheel and all the old clutch and 3-speed stuff will still work. do a search but I think it comes in as an '87 F150 with a 4-speed and a 302. There is also a clutch hole adapter braket for the late model block. These parts will have resale value when you get around to the auto conversion. If you can find a good deal on a used flywheel you may even be able to resell it later for about what you have into it. The only throw away part you will need to buy in order to keep the old 3-speed is a pilot bushing. Since you have plans on going automatic I will go against my own advise and tell you to keep your old clutch (unless it is in bad shape). That will keep the price down.

As for later when you get around to an automatic there are a few options. C4 is plenty strong. C6 is generally too big, heavy and long for a Bronco. You need something really insane in order to need a C6. The C6 will also need custom everything in order to install.
Then there are a few overdrive options. Either go cheap on the core and get an AOD then sink a ton of money into upgrades or spend a little more upfront and get the better 4R70W and not need to upgrade everything inside and you get more features as well. But to use any overdrive you need proper gearing in the axles to go with the overdrive and the tire size. Simply put it generally isn't cheap. But you can get your low gears and the highway too.
 
OP
OP
7

72-Madisyn

Full Member
Joined
Dec 21, 2007
Messages
211
Loc.
Medford
putting in an 89 linc. 5.0 motor. has just over 82k original on it, have the whole car for my donor so I am taking the fuel pump out of it and factory harness. I have a great c4 and c6 tranny sitting at my shop that I was wondering whether or not I should go that route as a cost savings. Found a flywheel for 60 bucks, found a clutch kit for 120. I know little things will come up with the swap but trying to stay under $700 now.
 

broncnaz

Bronco Guru
Joined
May 22, 2003
Messages
24,341
It should but you have to verify as some of the newer flywheels do have a different bolt pattern for the pressure plate. Just make sure your flywheel is a 164 tooth flywheel. If it came out of a mustang its a 157 tooth fywheel and wont work with your bellhousing.
New C-4 adapters run about $450 used about 1/2 that when you can find them.
 
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