350dd 2 or 3 blade

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Dabeetereater
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350dd 2 or 3 blade

Post by Dabeetereater »

just got this boat trying to fix her up a litte, its a stock 350dd, 13ft hartline glass boat, with ok poly on the bottom

has a 72 lxl 40 wood on it now,
boat goes ok but not great,

i have been doing a lot of reading but dont see much info on 3 blades on a 350 dd setup.

got a spring kit for the hei coming
194 204 cam kit
has a 600 sfm carb on it and a dual plane high rise intake
have some 1 3/4 headers also on order

will the 72/40 be ok for it?

i also have a buddy with a 78" 3 blade carbon sensetech with H blades, would that work for it or be to much prop on a dd setup
Last edited by Dabeetereater on Tue Jan 07, 2020 9:44 pm, edited 1 time in total.
350 dd 13ft hartline beater in the works

blu by u
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Re: 350dd 2 or 3 blade

Post by blu by u »

I ran a 68" 3 blade whirlwind excaliber. ran awesome. 2 blade whispertip would be a good choice too
chris

Dabeetereater
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Re: 350dd 2 or 3 blade

Post by Dabeetereater »

yeah this one is a 78 so its pretty big
350 dd 13ft hartline beater in the works

One Eyed Gator
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Location: Ocala,Fl

Re: 350dd 2 or 3 blade

Post by One Eyed Gator »

In a 2 blade a 68",70 or 72" would work. I ran a 72lxl38 wide blade on my .020 over caddy 472. Wide 2 blade will give you push across the rpm range where a narrow 3 blade will have good snap and have a narrow rpm range more like an old 2 stroke motorcylce.
I also ran a 72" 3 blade H on that caddy motor, 78' would be way to big. If you get the serial numbers of the 78" H blades and call sensenich they can tell you if the blades can be cut down at all or swap hubs if that prop has a med or large hub. I ran a 2.5" exhaust as well

Remember if you're only turning it 3000-3200 it may make 200hp and that rpm

Do a search on 350dd and look for comments by John Fenner He gives some good info on cam, carb and heads for that motor.

I ran my DD caddy for 10 years before moving on to a gearbox. It is all the small details coming together to make a dd run well.

Dabeetereater
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Re: 350dd 2 or 3 blade

Post by Dabeetereater »

i called senseich and they said it would work, im putting together a prety nice setup and have been reading a lot and think it should work good and have some torque. and after talking to the guy with the 3 blade it might be a 72" 3 blade not 78 but ill have to get a accurate measurement on it after its put together
350 dd 13ft hartline beater in the works

Gladesman06
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Re: 350dd 2 or 3 blade

Post by Gladesman06 »

If it's a 72 H blade it should work fine. A few things with the H blades you should know. The most important is to listen for any sound change in the prop. If you hear a whistling sound you need to check it right away. The H blades are well known for the leading edges to come loose and start sliding off the blade. Also they are not great blades for low end push. They are a blade that likes RPM. The only other thing and it's not really important is that they are pretty loud blades so get some good ear protection. Good luck and hope you are on the water soon.

Dabeetereater
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Re: 350dd 2 or 3 blade

Post by Dabeetereater »

Did some tuning on it got the 2brl on it and timing curve good and it turns 2800rpm. But it will sit there and take forever to get on plane.but this prop looks wierd like it's been cut and modified or something. But it goes on just needs more push. Gonna do the cam this week and see if that helps
350 dd 13ft hartline beater in the works

flcracker9
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Re: 350dd 2 or 3 blade

Post by flcracker9 »

A 72" 3 blade H is a lot of prop on a DD 350. Will it push the boat, yes, is it the best prop for that combo, no. Like stated previously, a 68" - 70" 2 blade is the standard for that combo. We (my Son's boat) run a 70" Q on a 385ci DD on a 12' hull, great snap, runs the hill pretty damn good for a DD, but you are trying to push a 13' boat. We have ours set on the 2-1/2" mark, and spin it right at 2800 on the trailer.
12' Open Palm Beach, IO-0470-L 260hp, 72" NGQ

One Eyed Gator
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Re: 350dd 2 or 3 blade

Post by One Eyed Gator »

My H blades pushed best at 2950 but would make your ears bleed. I would mess with the pitch a little to find the sweet spot for you setup. I spent a day on the lake adjusting the pitch a little at a time to find where mine performed the best.

What pitch make are you on to spin it 2800

Dabeetereater
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Re: 350dd 2 or 3 blade

Post by Dabeetereater »

I'm not running a carbon prop. I have a 72 40 wood stick. Turns 2700 to 2800. Idk how accurate my tach is. I got it running good this weekend it will run across some dry but only if i hit it with some speed haha. Feel like it needs more push. I got a line on a 72 34 paddle prop. Wish I could try a prop out before I buy one tho
350 dd 13ft hartline beater in the works

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Slidin Gator
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Re: 350dd 2 or 3 blade

Post by Slidin Gator »

Dabeetereater wrote:
Sun Jan 19, 2020 7:55 pm
Turns 2700 to 2800.

Feel like it needs more push.

I got a line on a 72 34 paddle prop.

Wish I could try a prop out before I buy one tho
2,800, you are giving her all she’s got Captain. We always need more push. Don’t waste your money on the lower pitch woody, it will over spin. Focus on tuning the motor for a bit more torque and then an adjustable carbon fiber when you hit 3,000.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

Dabeetereater
Southern Airboat Member
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Joined: Wed Jan 01, 2020 9:30 am

Re: 350dd 2 or 3 blade

Post by Dabeetereater »

got a 2 blade 70" terminator prop on it, turns 2900 no problem now seems to push great have not got it dialed in yet but mid range push seems a little less to me for some reason but bottom end and top end is great but only got to run it for 10 min before my distributor gave out
350 dd 13ft hartline beater in the works

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