so i got a strip tread on my block where the trany bolts on to and i was wondering what the size of the tap do i have to use to retread.

 

this method (re-tapping) will not result in a suitible repair. oversize and install a threaded insert if it's really bad, run a thread chaser through if only small damage. based on your wording, I would guess threaded insert is your only option.

measure the bolt. Metric threads are easy. probably M14 X 1.5

 

The damage isnt really that bad...just close to the tips thats kinda mess up

 

Chase it out with a tap then with the proper bolt to get all the way to the bottom, make sure the bolt you use to mount is long enough to reach almost to the bottom of hole to get as much tread grabbing as possible.

I damage is bad, then I agree with hondamark35 get a treaded insert...
94

 

Any decent machine shop can heli coil it for you

I had to do this to my trans all three holes for like $20 good as new! Maybe even better