Cam recommendations 572 blower
 

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


https://cimg0.ibsrv.net/gimg/www.off...92d1c86ce3.png

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

https://cimg0.ibsrv.net/gimg/www.off...1cd6d56053.jpg


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

Nice name btw,
My baja long ago ...:D


https://cimg5.ibsrv.net/gimg/www.off...5846c40523.jpg

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.

Asaltweapon is running a 4.5 crank, I personally would use a 6.7 rod in a tall deck block for that application. I'm not an engine builder, I was just curious. I've played with a couple BBC's with Prochargers, definitely not an expert.

While the blocks stroke thus displacement isnt up for debate, the camshaft is the focus of this post. Any info. related to the cam choice is welcome. I already own the 4.5x4.5 block. TIA

I don't know anything about the Merlin heads, Prochargers seem to like the 112 lobe separation.

Thats good info. Thanks

i think the best thing is to give bullet cams a call they have made all our marine cams even a blown 598 turning backwards they are the best and are great on the phone they even build many nitro cams for many teams..... they do have the knowledge to guide you

I've focused my attention the last couple months on making cam, valvetrain and valvespring selection easier.

allmondmarine.com/cams/

The chart on this page is focused on N/A power. Boosted peak power speeds will be several hundred RPM higher.

On each of the individual camshaft's pages, there is a valvetrain recommendation based on what you expect your max engine speed to be.

I'm working to make these cams available soon.

I've also built a valvespring calculator that I and others find quite useful: Spring Calculator

Really neat and informative site. Never heard of them til now. Rockers look exceptional. I focused on their stage 5 cam.

OP - Whats your peak rpm goal + - ? My jones SR cams are 255/259-724/724 in my NA 565’s peak @ 6k. 4.25 stroke but I’d guess in a FI 4.5 stroke would be near the same.

I am surprised they use std journals on all. Std lifter size or .904

6,500

I would have went with Mike but it was Covid and his cams were weeks out Comp had cams in stock .

https://www.yellowbullet.com/threads...s-cams.245015/

Hopefully those shlt show times are behind us. But yes Mike is a great guy to deal with and been around for a minute. Lol! I filled out his form and he got right back with me. (Beginning of Covid) and lucked out. I was very glad I went with him and their lifters as well. Cams were spot on and at that time I was so sick and tired of laying head down on the pillows at night and wouldn’t stop thinking about cam specs. I was finally done with and extremely happy! The plus side was they sound absolutely wicked to boot. 😂

He comes from the “OG”old school lunati, ultradyne / bullet crew (era). But stays with current times as well.

Like bangbros mentioned bullet is a great Co also.

Nothing against comp at all but there’s much more out there than just comp and you get more of a one on one care which these days are slim to none.