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What prop do y’all recommend for a 12ft with a 350 sbc DD

I got a great deal on a deep hull 12 ft airboat and I have a 350 SBC that’s been bored out .60 over with flattops and a .480 lift cam and a .280 duration and am going DD until I can afford a gear box or a belt drive and I’m wondering what prop y’all would recommend. I have a guy that’s willing to sell me practically a brand new 72” whirlwind whisper tip 2 blade for $900 and another guy that has a 72” LHR 6 blade warp drive for $600. What do y’all recommend?
 
A cam very close to stock is usually the trick

When talking duration there is an advertised duration and a duration measured at 50’ use the duration at 50’ because it can’t be manipulated.

Think of duration as a number that plans out where your engine will make its power. While not the only factor a lower number brings your power (torque) in early. A larger number will bring it in higher up the rpm scale and tend to produce more power up high (horse power).

Direct drive is limited to the props maximum revolutions per minute. The prop can’t spin up a lot of RPMs it will fragment and become a grenade. Generally speaking based on design and length most direct drives are limited to 2750-3100. The safe maximum is determined by the manufacturer.

If it was me for a Direct Drive boat I would not exceed 206/212 in a small block @50’ lift

Your wanting your peak torque at 2100-3000 rpm.

Big cams, big intakes and heads are great up at 6,000rpm but as stated they will make a direct drive boat a pig.
 
I got a great deal on a deep hull 12 ft airboat and I have a 350 SBC that’s been bored out .60 over with flattops and a .480 lift cam and a .280 duration and am going DD until I can afford a gear box or a belt drive and I’m wondering what prop y’all would recommend. I have a guy that’s willing to sell me practically a brand new 72” whirlwind whisper tip 2 blade for $900 and another guy that has a 72” LHR 6 blade warp drive for $600. What do y’all recommend?
I had a wisher tip on a dd350 boat and it was a turd but pushed it dry some
 
I got a great deal on a deep hull 12 ft airboat and I have a 350 SBC that’s been bored out .60 over with flattops and a .480 lift cam and a .280 duration and am going DD until I can afford a gear box or a belt drive and I’m wondering what prop y’all would recommend. I have a guy that’s willing to sell me practically a brand new 72” whirlwind whisper tip 2 blade for $900 and another guy that has a 72” LHR 6 blade warp drive for $600. What do y’all recommend?
72" WT is too big for that motor. Just a WAG, but that setup might be hitting 150 Hp at 3,000, just wanting to start running. Put a stock cam and a 2 bbl 350 CFM and you will have 160 Hp, but torque from idle to wind up.

As is (or all torqued up), buy the warp drive and send it in for refurb. Have them trim to 68" if possible, 70" will work (The tips are worn as is). Try it out with 4 blades and turn to 3,200, try again with 6 blades, same 3,200 RPM. You will end up sticking 2 blades in the boat for spare.

Geared advice is completely different.
 
Well I did a search for my posts on DD build specs, it seems they are gone since the site was updated.
In a small block Chevy DD application whether it be 350/400 CI, you want to run a stock cam for a 267 V8 the part# was Mellings CS-711, now saying that you have flat top pistons, this might push the CR too high for pump gas but worth a shot, if you can find a set of 267 heads, tiny valves, intake runners, bolt them on, another thing, 305 aluminum truck intake 4V adapted to a 390 holley properly jetted, you will see that it will snap a 72" prop to 3000 with no hesitation.
 
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