Out of a Ford parts interchange book. 221,260,289 motors crank ID as 1M. 302 ID as 2M. 351W ID as 3M. 351C/M, 400M as 4M and 4MA. 1985 was the year the balance weight changed from 28 to 50 oz. The front balancer must match the application weight. Note; balance is considered to be with all stock original oe equiv. parts and not a change to some other rods and pistons in the rotating asembly. To do that you must have the final selection balanced by a shop. HI PO rods used a wider heavier balancer to compensate Flex plates and flywheels were 157, 160 and 164 tooth depending on application. There were several front balancer designs and diameters from 6-3/8 three bolt to 6-1/2" four bolt plus different widths to accomadate various pully combinations. If you don't have a complete rotating assembly and know the source info, take care with matching the assembly.
Im building a 86 302 with a 164 tooth 50 oz flywheel . My c4 bell housing is for a 157 tooth flywheel . I cut the weight off the 164 & welded it to the 157 & i am wondering if this will work ok or does this need to be done by a machine shop so the weight can be placed in a certain place & weighed be for welding it in place ???????
Not a good idea. Yes, the weight has to be placed correctly. The imbalance is determined by the counterbalance weight AND its distance from the axis of rotation.
You need to get another 164 tooth, 50 oz. flexplate and also a large bellhousing for the c-4. The bellhousing just unbolts and bolts back on. Or find a 157 tooth 50 oz. flexplate and keep the smaller bell. that's probably the easiest.
Ditto, the size and weight of the counterweight is determined by the distance from the crank centerline.
TCI and B&M both sell 157 tooth 50 oz flexplates for what you're doing. I just bought the TCI plate thru Summit Racing for $85. There were no factory applications for this, so these flexplates are aftermarket only.
Wow, can't believe this thread was dug up again. Four years old and it takes on a new life. And that 302 is still in the utility room. One of these days I'm gonna find something to put it in......
