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UncleBubba

Well-known member
My Dad is going to build a 350 dd for his boat . I would like some input on what cam to use. It's going on a 13 ft glass boat. He has a 72x36 wide blad prop that he would like to use. Alos what other things I may need to do. Like head work?????????????? Pistons ?????????? and all the other good mess I may need to do to it .

THANKS FOR ANY HELP.
 
Unclebubba,

Did ya'll sell the motorhome yet?

Get one of Watethunder's rocket LS1 engines to make the boat climb trees!

Basketcase
 
yes on the motor home. I with we could get one of thunders engines for it but this is being done on a slim budget. and we are trying to get him going again.
 
your not going to put a box on it. dd is not that good unless your running water all the time. unless you put a 500 caddie on it then you can run where you want.
 
we would like to. But you know the drill NEED MO MONEY. So we are going dd for now then later on a box. The only hope for a box rite now is to sale are 14 fl panther hull that we have.
 
I ran a 350 dd on my boat the first couple of years I had it. If you can find a 500 caddy I would do that instead of the sbc if you are going to stay with Direct Drive. The 350 chevy will not turn a 72 x 36 paddle prop. I was running a 72 x 30 paddle at 3000 rpm. This winter I changed over to the 500 caddy and can turn a 72 x 38 paddle at 3000 rpm. The caddy only weighs around 50# more than the chevy. If you need to run the small block chevy I would suggest a 400 or a 383 stroker and a warp drive prop. Just my opinion and experiences.

Dan
 
i'll add a bit more info to my last post. The boat ran well with the stock 350 dd... it just wouldn't run dry. My boat is a 1978 panther aluminum hull. 15 foot by 7.5 foot and poly on bottom. I could get to shallow water and some sand and get back off. Never had the guts to try it on grass but the now it will run grass better than wet sand. I would suggest though using a warp drive prop because it will spin up faster and you can adjust it to how you run. The wood paddle I used did not impress me at all and it was very noisy. You are also running shorter boats that are probably lighter than mine. I was running bone stock engine. I'm sure with some headwork and a cam you might get better push than I did. I had a comp cams 4x4 extreme energy cam in my first engine that I never got around to putting in the new one. That is what comp recommended I use. Waterthunder is the Small block guy who would be able to answer your upgrade questions.

Dan
 
We are more than likely with a year going to put a belt drive on it. Just for the most part dad would like to the boat going so he can go froggin, and ridin. At this point runnin the hill at this point ain't no big dill.
If it was my boat I would go caddy' but it not it's dads.
 
Hey unclebubba iv'e got a guy i ride with here in st.cloud run's a sbc dd. and it wirks great his hull is a 13 ft. bandit riggin is built pretty light his motor is .030 over 350 with flat top pistons stock vortec heads crane spec. rv cam edelbrock intake and 600 holley his boat runs dry very well he put poly on last year and that slowed him down just a little but he say's the two biggest changes came when he put the vortec heads on and when he went to a carbon prop with the stock 76cc. heads and wood prop it would not run dry. good luck hope this helps if you want any more specs. let me know and i will ask him.
 
BUbba: My 2 cents worth is ... why build a motor for a dd application when that motor probably won't work very well with a box later on. You see with dd you have to try and I repeat the try part to get your power curve as low in the rpm range as possible. with a box you want the power curve up a good bit higher. If your gonna build why not look on airboat trader and pick up a caddy and then you have a dd motor worth the effort to put it together. You are just throwin good money after bad to build a dd with plans to go belt or gear later. the prop won't work the engine stand will require serious modification. the weight distribution changes whern you move the engine forward to accomadate the drive unit. It really is a royal pain to do that I would seriously consider gettin a caddy to start with and do it that way. I don't believe anyones dd small block chevy runs dry all that well I spent way too much time pullin, winchin and prayin when I ran a dd 350. Runnin dry aint the same as pullin up on the bank and gettin goin again and sometimes that is a chore with dd. Sorry not wantin to make anyone mad but hate to see ya'll waste money... go with a caddy and you will be able to run some dry and you will get great gas mileage and be fairly dependable.
 
Asking_Price: $1.00
Owner: H. Maddox
Address: 2032 second kolomoki road
City: Blakely
State: Ga.
Zip_Code: 39823
Phone: 1-229-723-5866
Date: August 01, 2005
I am disassembling two 472 cad engines. If you need good parts call me at 1-229-723-5866 I can't take e-mails. BLOCKS $125.00 Heads $140.00 a pair CRANK $100.00 OIL PAN $25.00 Cam $25.00 Intakes $20.00 Pistons $50.00 CRANK Serial# 1486424 Head# 902 1.25hour north of Tallahassee, Fla.
 
Asking_Price: 600.00 obo
Owner: Fritz Nelson
Address: 5400 Calamondin Ave.
City: Cocoa
State: Fla.
Zip_Code: 32926
Phone: 321-863-6882
Email: nelson123 @mindspring.com
Date: July 28, 2005
1975 500 Cadillac motor complete on a jack stand and I also have a turbo transmission (350) that will fit it. And a 1976 500 Cadillac motor in parts but does run. I took it apart to move it.


--------------------------------------------------------------------------------

Asking_Price: 750.00
Owner: Jerry
City: Davie
State: FL
Cell_Phone: 954-658-2424
Email: dixiedog20@bellsouth.net
Date: July 28, 2005
500ci. Cadillac complete , alt. , distributor , headers , prop adaptor
 
Asking_Price: $450.00
Owner: Ken
Address: 7201 Gulf Blvd.
City: St. Pete Bch.
State: FL
Zip_Code: 33706
Phone: 727 367-2171
Email: kingpinska@aol.com
Date: July 26, 2005
1 set of 1969-1970 472cid. Cadillac heads 1 1976 500cid complete engine
 
Asking_Price: $950 each
Owner: Clint Miller
Address: 6541 S.W. 132 ct. circle
City: Miami
State: Fl
Zip_Code: 33183
Phone: 786-344-3432
Email: Sirmill3@aol.com
Date: July 12, 2005
two 500 Caddy engines, complete. They are off of commercial airboats. The airboats were rebuilt and 500's replaced with 454's. They have alternator, distributor, carb, starter, headers, etc. Pretty much ready to run, just add gas and wiring. I also have prop adapters-$75.00 each, engine stand-$100.00 each, and possibly props.

OK I WILL QUIT NOW BUT YOU GET THE IDEA HOW MUCH YOU GONNA SPEND ON A DD 350 ???
 
I understand what you are sayin but my dad is bull headed so maybe he will look at this thred. If it was mine thats what I would do but its not

My next one will be caddy NOT a Ford (sorry Basketcase)


But its the truth.
 
DD= Cubic Inches....Small displacement engines have NO power at 3000RPM..Just physics....IF you HAVE to stay SBC and only a 350....Put Truck/small chamber 305 heads on it, and steel shim head gaskets to step up the quench, with a RV cam, then advance it about 4 degrees with a small dual plane intake, and the smallest 4-barrel you can find (390 Holley would be my suggestion)....It won't match a Caddy...But will be cheap, and make the gearbox conversion later a lil easier. Then you just change cam, intake and carb... Not my dream engine by any means, but just suggesting some of the best low-buck ways to make a 350 make torque. You may even surprise a couple ill-tuned Caddys w/it. ;)

Felber
 
Gear drive , Cad or small block . Do it like a investment More bang for the buck :D 141 and felber got good points :shock:But remember noise is going to be a issue anything you do now ,do for later , remember the we build them now has got to be for the future Me, and 141 and tiderunner live in a county that already has almost stop us with our boats we have to comply We are trying to ride the tide the best way we can .talk to pop tell him .Me and you are not lite in the seat me and you need some reduction. in our boats too :lol:
 
350 direct CAN run the hill, I see it every time I get to go riding.

Call Crane and Comp Cams for their recommendations.

305 heads will make a 350 sound great and have good throttle response, but with a stock or smaller-than-stock cam, your cylinder pressures will be VERY high. You'll have detonation probs unless you use 93 octane and probably need octane booster too. Light boat will help a lot too.
 
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