Cjs1969

Hey guys, I have a bone stock Olds 403 in my 1969 cutlass. I'm just looking for information on what perfomance parts I can put into it it with actually removing it from the car?

captjim

The best thing about a 403 is the big cubes in a small package. Weak points are cam, heads, and compression. IMO, the besy way to wake up a 403 is to replace the stock heads with mildly worked old 350 heads. This will raise Cr up to the mid 8.xx to 1 (stock is around 7.8 to 1), improve flow, and allow for a cam upgrade as well.