pullmytrigger

Its going to be a year or so before I can do the 383 buildup, but in the intrest of longevity in the meantime I want to replace the valvesprings and the timing chains, any suggestions on manufacture, (2) 89 350 magnums, centre bolt valvecovers.

axapowell

If you are replacing stock valve springs...I'd go with Comp Cams replacement springs. Call them direct, or like Summitt or Jegs, and they will guide you if you know the spec on your cams. As far as timing chains and gears, Cloyes true roller design has worked well for me. Check part number CLO-9-3100 (about 65.00 each set)

powerqrudy

Guys, does anyone know the specs on the stock cams in a 350cid 260 hp marine motor or even a 270hp magnum. They can not be that all different. I was thinking 245 duration ??? who knows..any input would be nice. Thanks

GMM

According to Dennis Moore a common Hyd. flat-based lifter camshaft used by Mercruiser has the following specs. [email protected], 200 intake, 212 exhaust, lift of .400 intake, .410 exhaust with a LSA of 110.

pullmytrigger

Hey guys, Im going with a set right out of the GM parts cataloge, high silicon content #10134358 out of their ZZ4 345hp crate engine, their best spring that will fit in my stock spring pockets, $20/set cheaper than Comp 981 and like $60 cheaper than Crane.