Charly9g

Hi all. What is the BEST adaptor plate to use on a 1971 455" bell housing to 4L60E Trans. I've heard that some are not very accurate as far as the bolt holes are concerned. Thanks, Bill. Charly9g/wfg4u@aol.com

Charly9g

Hi all. Looking for the BEST adaptor plate to mate a 1971 455" to a 4L60E. Tanks in advance. Charly9g/wfg4u@aol.com

joe_padavano

The "accuracy" of the bolt holes is irrelevant since they are clearance holes. The alignment dowel pins are what does the locating. The issue is that some of the adapter plates only pick up four of the six bolts. Select one that picks up ALL six BOP bolts and at least six of the seven Chevy pattern bolts (the top center bolt on the Chevy pattern can be left off with no ill effects).

joe_padavano

I merged your two identical posts since asking the same question in two different sub-forums rarely gets a better or faster answer.

olds 307 and 403

I believe Proform? makes a thicker silver coloured one, around $100. I bought the cheaper gold coloured one. Mine didn't have threaded holes, so only six of the potential 8 bolts went in, some have the hidden ones threaded. I only have a mild Olds 350, make sure you have a high quality one for the extra torque. Also you will need spacers at the torque convertor, I just used washers. Otherwise the convertor will pull out of the pump too far and leak.

Charly9g

Thanks olds 307....... I'll check on Proform. Charly9g.

joe_padavano

Can't say that I have any experience with ProForm, but I do know that Trans Dapt has been around forever. Their P/N 0061 is one of the best adapter plates.

Charly9g

Many Thanks Joe. Will this adapter work on the 4L70E, 4L80E also. Thanks again. You are a WEALTH of knowledge. Charly9g.

joe_padavano

This adapter works on any trans with a Chevy bolt pattern.

olds 307 and 403

That looks like the one I was thinking of.