bore stroke CI
0 3.735 3.478275603 305
0.01 3.745 3.478275603 306.6353858
0.02 3.755 3.478275603 308.2751443
0.03 3.765 3.478275603 309.9192755

Are these numbers right?

I searched til I found the 305's bore size. I then used excel to calculate the stroke for a 305. I'm guessing the stroke is not usually carried out 9 decimal places.

My father rebuilt my 305 and put it back in with 020 over pistons.

I've been wondering if a chip is needed. With 3 more cubes, I'm guessing I don't.

later...

 

No chip is needed.

 

Not unless you've done a lot of mods. Check out the TBI board, they have a few things you can do to that motor of yours.