what's the diff, M vin J vin?

[lvemy3100]

does anyone know the diff between the M vin and J vin 3100 motor lifters

[1988GTU]

I think it has to do with the rocker setup...

[mjf1212]

Re: what's the diff, M vin J vin?

does anyone know the diff between the M vin and J vin 3100 motor lifters

GM part number for the lifters is 17120070 for both VIN M and VIN J.
Doesn't matter whether the rockers are roller fulcrum or plain stamped. VIN M can be either with '96 up rollerized IIRC.

MJF