i want to swap my 3 speed out of a 68 mustang a c4 i just picked out of a 70 truck that had a 240 inline 6. i have a 302, the bell housings are different it seems, starter looks to be in a fdifferent place too. do i need a new flywheel? also the rear mounts seem to be an inch or 2 back and are 2 bolt rather than the 1 center bolt in my 3 speed so ill have to re-do the tranny cross member... is there another C4 that would be an easier swap? i could off this one pretty easy. already bought a shifter kit for a C4 so not looking for anything else really. just the easiest to swap without modifying my cross member mounts and starters/flwheels, et.c -Rob
The bellhousing bolt pattern is the same on the 302 and 240. You need to use the bellhousing that came with the C4. If you are going from a 3spd manual to a C4 auto. You'll need the automatic block plate, starter, flexplate. And make sure to get the correct balance flexplate for your motor(either 28oz or 50 oz depending on the age of your 302 ). If I'm not mistaken the 3spd transmission mount should bolt onto the C4. So you'd just need to relocate/modify the crossmember to get it in the correct location for the C4.
yeah the bellhousing pattern looks the same. also, the motor is out of a 69 mustang, not sure what flexplate. and the starter, i could get a ministarter that and would look for something that fits that flexplate right? as far as the rear mounts, it looks like this tranny has 2 rear mounts, one on each side, whereas my 3 speed had 1 bolt in the center, no biggie, i can fix that, just want to make sure i'm not doing something silly. i also bought a gennie shifter already for a c4 so want to make sure that fits too.
The bellhousings are different... I forget what year it was, I *think* 70, but they switched from the 157 tooth flexplate/flywheel to the 164 tooth flexplate/flywheel, theres "early" converters and "late" converters for C4's. If I recall you can swap the WHOLE deal out, ie put converter, tranny, flexplate, starter, blockplate, and it will work, but otherwise it won't be a direct swap. I'm goin' from memory here though, so I might not be 100% accurate.
yeah thats what it looks like, im cool with that, just want to make sure i get the right stuff as far as flexplate and what not. looks like that stuff is going to cost me twice what the tranny did!
For a 69 302 you will need a 28oz imbalance flexplate and one with 164 teeth. If your current transmission is a manual transmission the bellhousings will be different but the bolt pattern(where they bolt to the block will be the same.
I got a 164 tooth flexplate off a 71 351C that I'd maybe trade something for thats in good shape, IIRC its the same but you might want to check.
no matter what year your engine is, the bellhousing has to match the flexplate you got. 157 tooth flexplate and bellhousing, OR 164 tooth. Then, depending on year of engine you need your flexplate to have the appropriote balance. 1969 should be 28oz, not 50oz. I guess your first step would to get your bellhousing (and block plate), then match up your other stuff
The truck C4 off a 240/300 will be a 164T And the 69 302 needs the 28oz. So you need the flexplate with 28oz imbalance and 164T.
Does the bellhousing that came with the C4 bolt to the pump, or the case? Does the dipstick go into the case or the side of the pan?
Here you go this website will help you definately tell which bellhousing is on your C4. This site has the info: http://mmerlinn.tripod.com/trans/fdc4f/fd6c4bhm.htm And this one has the pictures: http://mmerlinn.tripod.com/pics/fdc4f/f71pc4f.htm
ok, so the flexplate, automount, and starter i have that straightened out, just want to make sure...the rear mounts are all teh same on C4's right? the two mounts in the rear?
I've never seen a C4 with two mounts on the rear. All of the C4's I've dealt with have had the standard rear mount that bolts to the bottom of the tailshaft housing. Could you post a picture of yours?
yeah ill post when i get home. maybe im missing something. my 3speed, is just a bolt into the center of the bottom of the rear of the tranny, this one looks like 2 bolts that are on each side on the bottom of the tail housing. am i missing maybe a mount bracket? would be nice to not have to modify my cross member, but it seems the holes wouldnt align in any case. but...ill double check again.
OK I understand what you are talking about now. What you are seeing is just two studs on the transmission mount. The mount itself bolts to the bottom of the tailshaft housing or a metal bracket that is bolted to the tailshaft housing. You should be able to unbolt the mount itself or the bracket from the tailshaft housing of the C4. Once you have that unbolted you should be able to unbolt the mount from your 3 spds tailshaft housing and see if the mount will fit the C4 tailshafthousing.
ah, see, thats the thing. im not sure my 3 speed was mounted properlly in the back then. all i have is a trannt cross member, with a flat plate and a slit cut in it.....the rear of the tranny rested on that, and there was 1 single bolt going from underneath, through the welded plate on the cross member, right into the tranny in the center. does anyone have any pictures of the mounts on either? id redo my whole cross member so i could make it removable, but my wishbones are kind of attached to the whole setup so its going to be a pain in the ass. it sucks its not removable anyways, but ill have to figure something out.
The two hole I circled in the picture are used to bolt the mount to the C4. The two studs should point down. Are those studs threaded? They are suppose to be two threaded studs there but I can't tell in that picture. Your 3spd should have either wide bolt pattern(the holes I circled ) for the mount or the inline bolt holes(like in the center of that mount ). So your 3spd is solid mounted to a plate welded to the trany X-member? If your 3spd has the inline mount bolt pattern(which it sounds like it does ) then you'd need to fabricate an adapter plate to bolt the C4 to the plate you've already got.
Solid mounting the C4 isn't the best idea though. Because if the motor rocks it could break the tailshaft housing. It would be much better if you could add some kind of mount that would allow a little give. But the stock C4 mount is probably way too tall.
ill try to figure something out. im going to mock it all up tonight and see how it mounts up now that i have the flexplate/starter/block plate squared away and ordered.
The Jalopy Journal
