I'm building a similar setup for my 76 swb chevy.

010 4 bolt block
400 crank turned, drilled and knife edged
6 inch I beam rods
Kb flat top pistons forgot what the cc of the valve reliefs should be around 11:1 with 65cc heads
vortec 062 heads off a circle track crate engine
RHS 23 degree ez efi/carb single plane intake
Undecided cam and carb

One thing to look out for with the vortec heads (atleast the 062) I'm not sure how the bow ties come but the RG clearance on the stock head allows for only around .460" of valve lift before the valve retainer will hit the top of the valve guides. Alexsparts.com makes a spring and retainer kit that allows for .550" lift without having to have the heads machined and have the guides cut down and the seats cut for bigger springs for 100 bucks. Also FYI stock size sbc valve springs will not fit vortec heads without the seats being opened up. Check out alexsparts.com for his line of vortec head stuff. He's got everything you'd need even the valve spring seat and guide boss cutting tool if you wanted to DIY.





Sent from my iPhone using SoCalJetBoats

From a horsepower standpoint, my vote for the Bowtie heads with the larger Crane Cam HR-284-2S-12 IG cam.  I like your cam choices, either should work well in your application.  Both are ground on a 112-degree lobe centerline and looks like they are ground advanced 5 degrees to a 107-degree intake lobe centerline.  Either should work well with TBI and have a smooth idle.

If you are expecting more operation in the lower RPM range, my vote for the smaller Crane 2032 Cam.  Match the build to your intended use.  How often will you be running at WOT or racing?  If you are mostly wakeboarding or cruising, you will like the smaller Crane 2032 cam better.

With your pistons at zero deck, your combination will have around 9.6:1 max compression ratio.  I would recommend tightening up your quench by zero-decking your block to maximize your compression and resistance to detonation.  You should be able to easily run pump gas.  You might even get away with running the cheap stuff.

I would expect 400 to 430 HP in the low 5000 RPM range with > 450lb/ft torque around the mid 3000 RPM range, on pump gas.

Cheers,

Joe

P.S.  Sorry, I am not qualified to comment on your outdrive or how it will work with this engine. 

That's a lot of can for a 383.....

Potentially if you go that route I would recommend playing with the rocker ratios on the exhaust. There are much better can grind choices out there.  The GM Performance Parts "Hot Cam" is among one of them.

Your best bang for the Buck would be to keep an eye out for a DuoProp lower.

Sounds like a sweet project.

Sent from my SAMSUNG-SGH-I927 using SoCal JetBoats mobile app