Maximum overbore on a 289/302 block

Cobra Pack · #1 (**permalink**) 02-27-2005, 07:15 PM

I am going to have a 331 stroker built in the near future for my Kirkham 289 FIA. I am curious if 40 over is too aggressive or whether I should stick to 30 over in a rebuilt block.

Thanks in advance for your advice.

Mike

Dennis Kelley · #2 (**permalink**) 02-27-2005, 09:03 PM

I would not go over .030 Without having the block sonic checked.

Later Dennis

bkozlow · #3 (**permalink**) 03-02-2005, 05:17 PM

Cobra Pack

60 over is the max for a small block. I do not recommend over 30 as you are now getting into custom pistons out side the normal stroker kits. Aside from weaking the block. I had a new block and went 331 as a stock bore stroker was going to cost a fortune compared to the most common 30 over. So, I went 331 not 327 and had to bore a new block. 40 over will cost you a lot of money and the extra one cubic inch is not worth it.

Bill K

351cuin · #4 (**permalink**) 03-03-2005, 11:34 PM

Your getting some good advice! From my experience I believe 30 over is your best move. First it will allow you to go to 40 over if you lunch an engine ( hopefully not ) And second less potential for overheating. But I firmly believe that 40 ove is the max.