Looking to cam up a 572 dart, hyd. roller, 345 heads Merlin, valves 2.3 I / 1.88 E, procharged 6-12psi, 1400 Dominator, 6500 redlined, 26' 4000 lb. American Offshore catamaran. Guessing around 112, 264 dur, 680-720 lift. Those are just some random suggested specs. IDK. TIA Anyone got a similar setup and love how your cam rolls, let me know what you love and why.

Are the 345’s cnc’d or ported? I wouldn’t go to crazy on lift. Duration seems in the ball park. Ck out the comp lobes icdedpple had or has in his 548 builds if you get a chance. If you can’t find the thread via search let me know or he’ll likely chime in.

If you’re heads are stock I think their gonna be a choking point. JMO


Just for comparison only but still a good read!! Try and copy and paste. Cam below was one Dan jones spec’d however I don’t believe he went that route… can’t keep up with him! lol. I will say the cams he spec’d and ground for my na 565’s are spot on and very easy on the valvetrain and make awesome power all the way through!!!!

https://www.offshoreonly.com/forums/general-q/374052-tunell-raaammm.html

Mild porting done on heads. Plus exhaust raised .0600

This is what I ended up with .
Comp cams marine grind. Easy on the valve train.

It pushed a mid 80s tank to triple digits.
8# of boost
Dart CNC pro 1 heads




26' and 4000lbs , thats is going to scream.!

Nice name btw,
My baja long ago ...

Came so close to buying one of those 26 AO’s for that same reason. Sucken gas and haulin azz! 😳

Did you use a 4.5 or 4.375 crank ?

572 ci has 4.5/B x 4.5/S. Hope this helps. If I had 4.375/S, I wouldnt have a 572. Thanks

I believe the Chevrolet crate 572 is 4.560 x 4.375, that's why I asked. I think the 4.5 crank is better for a boat and I think it would like a little more cam than a shorter stroke, but it's only my opinion.

GPM,

Though my readings here on OSO, I think the consensus is that a 4.375" stroke is better for a marine application due to rod angle and prolonged high RPM running. Many here advocate for nothing above a 565 for this very reason.

Thanks. Brad.