What would a carbon prop do for my direct drive SBC. I have a 12ft glass hull and my SBC is a brand new bone stock GM 350 Crate Motor, 4 barrel Edelbrock Carb and manifold. I havent even tried running dry. It wont push my 72x34 wood prop more than 2700. WOuld a carbon prop spin faster since it is lighter? Would it make my engine not have to work as hard? Would I get more speed and a better hole shot? Thanks!
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Carbon Prop on Direct Drive?
- Thread starter novaalex
- Start date
SwampMatt
Well-known member
You've got a lot of pitch for that motor. If you had less pitch, you'd be able to get a few more RPMs out of it.
More RPM = More horsepower.
You can get less pitch with a different prop, or with the carbon fiber you'll be able to change the pitch and use what is best.
DO NOT SPIN IT TOO FAST. Read & follow the instructions.
As for the other questions.... There are a lot of knowledgeable folks around here!
Good luck.
More RPM = More horsepower.
You can get less pitch with a different prop, or with the carbon fiber you'll be able to change the pitch and use what is best.
DO NOT SPIN IT TOO FAST. Read & follow the instructions.
As for the other questions.... There are a lot of knowledgeable folks around here!
Good luck.
crowhater
Well-known member
Keep the prop you have and buy a 50-100hp shot Nitrous system. When you get hung up and need that 300 more RPM just bump the goofy gas and you will start moving again. Two years from now when you hurt the motor buy a stroker kit from Waterthunder or Felber and make a 383 out of it. :wink:
nebraskaairboater
Well-known member
you will not be disappointed if you get a composite prop. A good prop for that engine is a 72" Sensenich Q series 2-blade. Night and day difference in the push. The hardest thing for me with my DD boats is to be "realistic" with my expectations.
CONTINENTAL CRACKER
Well-known member
i have alot of buddy's that started airboatin with dd sbc . they alway ran a 72 x 36 and would run dry.they also put the gas tank in the middle of the hull
as a dd guy ,composite prop yea , do you have plastic on the bottom? I have a sbf with a wood stick and can run dry if its in the mood (never when i need it ) and I'm turning a 68 x 36 much heavier than carbon . i like being able to adjust the pitch or fine tune it to my boat. i was told that if some was on hit the solid tip cut it off and increase the pitch to get home like the field repair idea to get me home . like carrying a fiberglass repair kit to fix a crack in your hull
walleye52753
Well-known member
From what I can tell there is always a few DD guys learing how to setup their boats on this website. (me being one of them) We started a direct drive thread for guys to post their setups and how well they work. Im just invitin ya to post any questions you can come up with on the thread. We can all learn from them.
My boat hasnt hit the water yet but I puchased a 72" whirlwind stump puller for my Direct Drive boat. Equipped with a 406 sbc...stock truck heads...Rv cam-14' combee hull.
Andy
My boat hasnt hit the water yet but I puchased a 72" whirlwind stump puller for my Direct Drive boat. Equipped with a 406 sbc...stock truck heads...Rv cam-14' combee hull.
Andy
On direct drive small block chevy you will only get about 230 to 240 HP due to the
prop not letting you get any more RPM's. First I would change the carb to a
edelbrock # 1404 which is a 500 CFM. Your not turning the motor hard enough to
use a bigger carb. Then I would use a 70 inch prop instead of a 72 inch. This will
let you run 2 more inches of pitch. I would guess a 70 36 wide blade or a 70 inch
carbon. Thanks, Chuck
prop not letting you get any more RPM's. First I would change the carb to a
edelbrock # 1404 which is a 500 CFM. Your not turning the motor hard enough to
use a bigger carb. Then I would use a 70 inch prop instead of a 72 inch. This will
let you run 2 more inches of pitch. I would guess a 70 36 wide blade or a 70 inch
carbon. Thanks, Chuck
You may consider a 5 blade warp, less rotating weight will allow it to turn up faster, also you have no problem pitching it to 3000+ rpm. On my 500 cad dd, going from wood to warp made it a whole new boat, esp the speed the prop would spin up, i was turning it 3100 rpm and it ran like a raped ape. Ive never ran a 350 dd so i dont know if the results will be the same as a caddy.
Robby Bondurant
Well-known member
I've got a cam that I had in my 350 DD that I need to get rid of. I was turning a 72x36 wide blade at 2950. Boat would run dry pretty good. I only ran that cam for maybe 15-20 hours because I wanted to get a gearbox and build a new boat. It's a 3000 rpm cam that made my boat really turn up fast and push hard.