O-360 Recommendations

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digginfool
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O-360 Recommendations

Post by digginfool »

Here's a topic that I'm sure has been nearly beat to death but here goes. A few weeks ago, purchased an 11' Don Davis with an H2AD on it. Boat had decent performance but a tad anemic. Engine runs great, definitely not the issue. Prop is a 68" Q. Took it up to KCOL over the weekend and put 73 miles on it and only burned 17 gallons. Problem was that, even with all the water up there, boat got stuck twice when I stopped above the water line on the green stuff. I know, it's sticky but still, a boat that light shouldn't be getting stuck that easily. Even when I stopped on dry and wasn't stuck, took quite a bit of rudder wiggle to get moving. Once moving, ran dry no problems. Maybe it's just because I'm used to the power of my car motor boat but it's just unacceptable. So, I'm going to do an engine upgrade. No room for a six cylinder without re-doing the rigging so that's not an option, plus, probably don't need that much power. I've done quite a bit of research on here and seen all types of commentary. I only want to do this once. I don't want to buy this and then want to add that or swap for the other. My needs are pretty straight forward; reliability, decent economy (I only have a 17 gallon tank) but want some kick in the pants when I need/want it. Primary use for the boat will be as a ride boat when it's just me, or me and another, frogging and chasing after my buddies that have really fast sleds. I can't see just going to a 180 since that only adds 20 HP so definitely a 200. And that's where it gets confusing. You see comments that a 200 that isn't injected won't actually make 200. You see where people wish they had gone with 10:1 on their rebuild but at the same time others that wish they had stayed with 9:1 because of the headaches getting their carb jetted right. Others say if they had injection, 10:1 no problem. Lots of opinions on cams, as well, and those opinions seem all over the place. So, long story short, if you had it to do from scratch, and money is no object but you don't want to spend a small fortune, what would you build and who would build it for you? Also, let's say you go all in, build an AV 200 with injection, cam, 10:1 pistons and upstack cylinders (yes, huge controversy on that one but I believe in cross-flow heads), how much power will the engine make? Would it be reliable and how would it tolerate just cruising around? Not looking for a full blown race engine but want to at least keep up with other boats and not worry about getting stuck every time I stop. BTW, I'm hoping some of the engine builders will reach out with some of their expertise, whether by PM or on this thread.
“When plunder becomes a way of life for a group of men living together in society, they create for themselves in the course of time a legal system that authorizes it and a moral code that glorifies it” - Bastiat

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digginfool
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Re: O-360 Recommendations

Post by digginfool »

Also, I'm perfectly okay with the idea that the best advice is "buy a stock AV 200 and don't look back." Just don't want to 'redo' after the fact.
“When plunder becomes a way of life for a group of men living together in society, they create for themselves in the course of time a legal system that authorizes it and a moral code that glorifies it” - Bastiat

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stroked470
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Re: O-360 Recommendations

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PM sent.

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Stewie
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Re: O-360 Recommendations

Post by Stewie »

Diggin that's def odd to be getting stuck on that little rig with 160hp I'm running my 12 ft rig rigged for.three same engine h2ad spinning a 69' Q series and my boat only has a 5 ft bottom and I have never had any problems running the hill or getting.stuck ! Have you done any adjustments engine angle, pitch ect? But if you are going to swap engines id def.go with the 200hp lycoming!!

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dblj006
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Re: O-360 Recommendations

Post by dblj006 »

Find somebody with a 180 boat and ride. The only way to know the difference is to experience it.

You can build a "200" with angle valve cylinders and high comp pistons but a "true 200" is about having the right crankshaft. If you find one of those gems buy it. The holy grail for 4 cyl Lycoming guys.
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Daniel Altman
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Re: O-360 Recommendations

Post by Daniel Altman »

Dave (WaterThunder) sold me a nice little A/C 4cyl NOS kit for my 320. I would RARELY need it but, it will keep me from getting stuck. The only green I cannot run is at the darn milk bus!
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Bubba
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Re: O-360 Recommendations

Post by Bubba »

Call Jurnigan and ask them what you just asked on here.
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ReelCracker
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Re: O-360 Recommendations

Post by ReelCracker »

Diggn' - if you're running polymer, you should try some "poly butter". We've had really good luck w/ the smaller 4 cyl. boats. Just ask Tonyld67 and a few others w/ 160 motors, I sprayed their hulls and they run dry well! Just spray a quart or so, let it dry overnight and you're ready to go. Might be a cheaper way to see if that's what you need before you rebuild your motor. I haven't re-applied for a month or so on my 180 boat and I can tell a difference even w/ all the water. It definitely rides better with the butter. Shot me a PM if you have any questions, I don't want to turn your thread into another poly butter thread. Good luck. RC

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Re: O-360 Recommendations

Post by diamondback0320 »

I also run the h model on a 11.6 diamond bk w alum. Riggin & is 2nd h2ad ive had & also had a straight valvle 180 on a cottonmouth & I have to say the h model I think runs just as good,& this boat im runnin now runs dry very well,not sayin it wont get hung up in some deep sheet but ant boat will get stuck,all in setup & fine tuning,& is great on fuel!

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Re: O-360 Recommendations

Post by diamondback0320 »

Damn jeff u must of bn responding same time as me lol & yes the slide does make a difference,matter of fact I need some now lol!

pirate
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Re: O-360 Recommendations

Post by pirate »

but a "true 200" is about having the right crankshaft. If you find one of those gems buy it.
How are they different?
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Re: O-360 Recommendations

Post by TIGO541 »

Dont waste all that hard earned money building a motor that really isnt going to make much more power than what you have. Ive owned the same motor and it is just as healthy as a 180 all day long. I suggest a small shot of nitrous after you put the poly butter on it and call it a day. It will be a different boat then. Good luck and enjoy that new boat
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gbstrike
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Re: O-360 Recommendations

Post by gbstrike »

Nobody mentioned prop pitch. Maybe set it up for more push and less speed. That boat should go anywhere. Good luck.
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boatair
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Re: O-360 Recommendations

Post by boatair »

What about changing the prop ?

diamondback0320
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Re: O-360 Recommendations

Post by diamondback0320 »

I run a water walker 68in at 6 degrees & turn 2900 & does what I want!

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Re: O-360 Recommendations

Post by Tommy Roachford »

Put a 350 sbc. and a gearbox on it :lol: :lol: :lol: just kidding. Good Luck!!!!!!

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digginfool
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Re: O-360 Recommendations

Post by digginfool »

Just to clarify, my current engine is an O-320 H2AD, which is 160 HP. The previous owner has the boat set up perfect for what it is. It rides very free yet doesn't hop until wide open and even then, very mild. Once moving, it does quite well running dry. I don't know what RPM it's turning as it doesn't have a gauge package on it. Only gauge at all is oil pressure and that's on the engine, so, at this point, I can't tell you if I'm over or under pitched until I can install a tach. I would imagine for push, probably won't turn much more than what it has (68" Q). My belief is that the boat is set up more for push than speed since the previous owner took his wife and child with him and would run dry at his camp.
“When plunder becomes a way of life for a group of men living together in society, they create for themselves in the course of time a legal system that authorizes it and a moral code that glorifies it” - Bastiat

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Re: O-360 Recommendations

Post by LSX1 »

I have had 2 0320 boats a 0360sv [180hp] ultra lite DB and now a hammant with a 0360AV [200+hp] no nitrous, but slight mods. All boats were 12' x 7' with polymer.I had to pick my trails wisely with both 0320 boats,and I got stuck like CHUCK often. My 180 DB was way better [never got stuck in the same places]. Now with the HAMMANT and AV0360 don't have to worry any more, point and go.Just a example 2 yrs ago I was down at polluted waters with AKA CONT520 with no water for a 150yrds from tree line, Me and one of his Buddys AKA FL CRACKER were the only 4 cyl boats I could see in the trees and we both came across that MEAN GREEN GRASS just Pattin the gas.You will not be dissapointed with a AV0360,+ your cruise RPM will be 300 to 400rpm's lower than a 0320. My prop is a 70'' Q set at the 2 3/8 mark turning 2800.THANK LSX1
Last edited by LSX1 on Wed Aug 20, 2014 6:45 pm, edited 1 time in total.

todd glover
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Re: O-360 Recommendations

Post by todd glover »

Pull your engine apart and stuff a 360 crank in it a160 case is fine add two dowel pins add 11487 pistons nice combo cheap

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Re: O-360 Recommendations

Post by lariat »

Is it poly or slick bottom? If its slick bottom, my old boat would be like I added 100hp to it whenever I would "re-do" the bottom.

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Re: O-360 Recommendations

Post by Seven3 »

I think your mind is already made up on getting a 360, but I say install a tach first and compare your RPM to your prop pitch before you make an expensive decision.

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digginfool
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Re: O-360 Recommendations

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I rarely make random decisions. I weigh out everything before I make a move. You spent 20 miles in the back seat. What did you think? Maybe I need to make you drive it.
“When plunder becomes a way of life for a group of men living together in society, they create for themselves in the course of time a legal system that authorizes it and a moral code that glorifies it” - Bastiat

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Re: O-360 Recommendations

Post by Seven3 »

And if you choose to still go 360, I'm sure I could find a home for that nice running H2AD for you. :thumbleft:

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digginfool
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Re: O-360 Recommendations

Post by digginfool »

Yeah, mister I'm buying a sled to put a 540 on. LOL
“When plunder becomes a way of life for a group of men living together in society, they create for themselves in the course of time a legal system that authorizes it and a moral code that glorifies it” - Bastiat

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Re: O-360 Recommendations

Post by Bubba »

Chevette or Corvette is the question? Get a 200 and be done with it.
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