Is there any diffrence in the balancing of a 75 302 flywheel for a FMX transmittion with a flywheel from a 1988 302 for a C6 ? Thats what I ended up with my 75 F100 along with the 88 transmittion. To me feels like it shakes alot more now but shifts alot better. Maybe I am just forgotten how it felt since took awhile putting it in. Any help would be appriciated.

 

302's before 1982 had 28oz imbalance. 82 and newer had 50oz imbalance. This was for manuals, but probably applies to autos as well.

 

It does apply to autos as well. The 302 is externally balanced so you have to use a flywheel/flexplate with the correct weight for the engines vintage. That is where the shake is coming from. I would not run the vehicle till you get the proper flexplate on there. You cant use a harmonic balancer off a 50 ounce imbalance engine on a 28 ounce imbalance engine or vice versa either.

 

What would possibly happen if I ran this flywheel. Till I get a correct one. Also yould youi know if a 79 ford truvk with a 302 and C6 would be the right engine vintage?

 

What would possibly happen if I ran this flywheel. Till I get a correct one. Also would you know if a 79 ford truck with a 302 and C6 would be the right engine vintage?

 

You're gonna start breaking things with a mis-matched balance. Not sure what your second question was, but I have a '79 302-C6, so clarify please.

 

if your 302 is a 75 the 79s balance would be the same. make sure you get the right tooth count for your transmission or you could have starter problems.

 

30 oz would start beaking things that quick? I didn't know. But I can get a hold of a 1979 ford with a blown 302 and a C6 for parts was wondering about if that would be the correct engine vintage. Was going to get it next year. Was wondering how many miles I could possibley run on it if I am not running hard? I understand it is not right now anyhow. Any help would be great.

 

That makes since thank you 70blue

 

Yeah that small weight difference does not seem like much but spinning at such high rpms it is alot of difference and will break stuff. I do not know for a fact if the older c6 and newer c6 would have the same tooth count. I would say it probably would but if not hopefully someone with more knowledge will correct me.

 

next question is how do I know what the imbalance was if I no longer have the old flywheel? according to summit there is a few diffrent ones and how bad would it shake I cannot see it just feel it.

 

If it is truly a 70s 302 you need the 28 ounce one. You can get the casting number off the block over where the starter goes and we can give you a definate answer.

 

68-80 the 302 used the 28 oz imbalance
81 and later uses the 50 oz imbalance

"You have to be sure of which crank you have, 28 oz and 50 oz have different counterweights. The crank, flywheel and damper have to all match. Check the crank casting numbers, 2M & 2MA are 28 oz imbalance, 2MAE is the 50 oz imbalance crank."

 

...Welcome clunker, to Ford Truck Enthusiasts!

See you on the boards. ….

 

I know you can't use a C6 flywheel with an AOD,the offset is different.I assume it won't work with an FMX or C5 either,that flywheel fits 1981 to 1996.
You need a 302/351W 164 tooth flywheel from 1980 or down to fit up a C6 to a 1975 engine. I have one almost new if anyone needs one.