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 prop advice for 40hdr with voodoo exhaust 
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Post prop advice for 40hdr with voodoo exhaust
I have a new 40 efi with a stock big 2 blade that came on it. Would hit 30 mph with just me and a 65 quart cooler and fishing gear. Put voodoo exhaust on it. Its on a 16/51 prodigy. Best I've got is 31.5 mph same load adding exhaust. Holds a load good loaded. And will run 30esh with Me/son and wife. was running 26/27 with 4 men 2 coolers and 2 alligators last year with gear. I'm thinking of trying a worked 3 blade. My question is what pitch would be good. Has anyone tried worked 3 blade on the new 40. What speed gains could I expect. And what pitch would it pull based off this info. hoping I can hit 35 plus if possible.


Tue Jun 11, 2019 8:32 pm
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Post Re: prop advice for 40hdr with voodoo exhaust
Stick with a worked 2. Itll handle the loads a bit better, dog better in grass and mud, and when worked for speed will be just as good as a 3 would be.

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Tue Jun 11, 2019 8:41 pm
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Post Re: prop advice for 40hdr with voodoo exhaust
Dig*

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Tue Jun 11, 2019 8:42 pm
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Post Re: prop advice for 40hdr with voodoo exhaust
Right on. Ill look into a worked 2 blade. Thanks


Tue Jun 11, 2019 9:58 pm
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Post Re: prop advice for 40hdr with voodoo exhaust
Russ is right. If you want speed empty, then a worked 3 would be good but it won’t carry a load at all and they are terrible in grass and mud. Your stock big blade would probably meet your needs with heavy cupping and sharpening without having to pitch it so you don’t lose your load carrying ability. What rpms are you turning empty at best speed and loaded at best speed?

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Wed Jun 12, 2019 5:22 am
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Post Re: prop advice for 40hdr with voodoo exhaust
There's the rub. Without rpms, you wont know if you can turn more prop than you have now. I bet 35mph with any load more than empty solo isnt achievable without more compression, regardless of prop.

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Wed Jun 12, 2019 6:44 am
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Post Re: prop advice for 40hdr with voodoo exhaust
Ill do some runs again to make sure. But i believe my best speeds are right around 4450/4500rpms.


Wed Jun 12, 2019 7:00 am
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Post Re: prop advice for 40hdr with voodoo exhaust
According to prodigys website. The stock bigblade is 12.25x10.
A hammer prop is 12.75x11. And a worked bigblade is 12x11. And a hammer prop would be much cheaper. Any thoughts or opinions on those?


Wed Jun 12, 2019 7:16 am
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Post Re: prop advice for 40hdr with voodoo exhaust
You're not gonna be able to turn a prop to get to 35 without engine work.

A hammer is a big heavy prop. For mud, not speed. You can turn it, but you'll prob drop a couple hundred rpms and not run any faster than now.

The worked big blade will prob get you another mph or 2, load carrying may be affected negatively, or be about the same. Depends on how it's been worked.

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Wed Jun 12, 2019 8:17 am
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Post Re: prop advice for 40hdr with voodoo exhaust
A hammer will be slower than your big blade. It is an 11 pitch and has a lot more rotating mass than the big blade. The hammer is excellent at carrying heavy loads as well as handling abuse from stumps and such, but it is not a speed prop. If you are running 4500-4600 with your current big blade, all I would do is sharpen it and add a little bit of cup, but no pitch. That should give you another mph or so, but if you pitch it another inch, you will probably drop your running rpms down to about 4200 which is not where you want to be running at wot. Are you running a cut skeg on your lower or a straight skeg, because if you plan on running a cut skeg, get it first and see where your rpms are at, because that will change those rpm numbers a bit at wot.

In conclusion, with what you are running, I would just add a little cupping and sharpen the blades and make sure it is balanced. That should keep you in close to the same rpm range you are in without sacrificing load carrying and hole shot. If not, I would leave it alone because you are already running pretty good speeds

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Wed Jun 12, 2019 8:26 am
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Post Re: prop advice for 40hdr with voodoo exhaust
Thanks guys for the advice.


Wed Jun 12, 2019 8:29 am
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Post Re: prop advice for 40hdr with voodoo exhaust
No problem bud

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Wed Jun 12, 2019 9:12 am
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Post Re: prop advice for 40hdr with voodoo exhaust
Do yall know what the stock rev limiter is on a 40efi? I havent really pushed the motor hard. I havent hit the rev limiter. I could trim the motor up and run higher rpms. Also where could i buy a worked 3 blade. I was running 31.5 at 4500esh but was afraid to go to higher rpms by trimming it up more.


Wed Jun 12, 2019 12:32 pm
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Post Re: prop advice for 40hdr with voodoo exhaust
My buddy has a worked 3 blade on a 2013 gator tail. Would his prop fit my mud buddy? If so i could try that and see how it does.


Wed Jun 12, 2019 12:57 pm
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Post Re: prop advice for 40hdr with voodoo exhaust
It should.

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Wed Jun 12, 2019 2:00 pm
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Post Re: prop advice for 40hdr with voodoo exhaust
The rev limiter is at 4750 on the 40 Briggs. No need to buy a worked prop, just get your current one worked bud

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Wed Jun 12, 2019 6:15 pm
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