if u r a boat mechanic please explain

in twin inboard applications(propshaft thru the bottom of the boat, not sterndrive), one engine turns opposite the other so, counter acting props can be used to tame torque steer. This is ususlly done by swapping hte timing chain set for a gear to gear, it allows the cam to spin the same direction, but the crank spins oposite normal direction. requires a special cam as well. If you are planning to repower your boat, I'd look at soemthing a little more mordern like a chevy power plant, easier to get parts for it. 4.3 V6 would be a nice size
 
aussie
no he anit on drugs! very common used with twin motors eliminates torque steering just like a tank on tracks you really could steer the boat by using the motors. go starboard or port.
mate the best thing you could do is stick with your motor and fix each problem at a time. you got enough steam with that motor. if what to go faster then buy a go fast boat. :beer:
 
i wish i had the cash to upgrade to newer one but i dont the engine on ebay is cheap and easy to rebuild and very narrow v so it may fit with not much effort and all the gear is there well the guy is right what he is saying and do u think my leg will be ok for that engine
 
well i think its a little low on steam it sruggled to plane and took a long time to get to 32mph with on 2 people on the boat im happy to spend money on it but im not sure it will pull a tube and holding it a 4000rpm for 10min ended up with 2 bent push rods
 
do a compresion test on your 4 cylinder, if its fair, pull the head, have it gone thru and freshend. Have the machine shop install the rocker arm up grades. try compition cams magnum rockers, they are cheaper than full roller and far better than what you have, you may have to install big block chevy rockers and studs. DO a search for cheap 460 ford rockers, a whole bunch of different ideas came up. Put it all back together with the stock 2bbl set up and try it out. At teh very least, you will have a good motor to sel if you want more power. My old roomate had a 17 Stingray owrider. I did a few minor mods to the 3.7 2bbl motor he had. Teh boat would run 55 mph with alight load. We used to pull two wake boards all teh time with four peopl in the boat. Don't give uyp on that four cylinder, its a good powerful motor. Easier to fix what you have than start a new
 
well thamnls spares just dont want to go the wrong way about it

i have to options buy that 302 windsor of ebay and hope it fits without too much trouble and rebuild it first

the next one is buy a edelbrock preformer head with the larger chambers fit the rollers and head comes complete with studs and rollers i was going to go for a 1.8 rocker arm and mod the manifold for a 600 cfm vac look may even pull the engine down and rering ti and get the cam ground to a mild solid but will it all be worth it in the end

i dont mind if i have to spend money in the end it will be a better boat it working out which way to go
 
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larger head chamber makes for lower compression ratio without the proper pistons. look just get a nos kit. you want power . power you will have doubled. but if abused you wont have any motor left.
 
step up here said:
larger head chamber makes for lower compression ratio without the proper pistons. look just get a nos kit. you want power . power you will have doubled. but if abused you wont have any motor left.
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thats not the advice im looking for what r all u guys going to start being dicks now:nut:
 
well i decided to do the 3.7 up watching some heads on ebay us the guy said he can post them for $175 so i will go the full hog do what ever it needs rebore . balance... rollers . mild solid regrind .timing chain. speedy sleve on camshaft . head stud kit..cut intake and fit 4 barrell plate..get dizzy recurved...fit a air fuel ratio gauge to get the mixtures right...electronic kit..solid lifter..3/8 pushrods...the heads need no work new well i have to buy 2 just thinking if i can enlarge the exhaust outlet on the transome....and too i may run it on a engine dyno to get a horse power and tork reading my mate said he will do it so when i have it done ill post some stuff well i better get of of here and start making some cash and i mite see if i can get rid of that harmonic balancer and find something better well cheers for now:cry:

ill post some pics of the engine when its appart if u like
 
Hi Aussie.

Sure, pictures would be great. 'love to follow projects such as yours.

Are you planning on using your V20 on a lake or the ocean? I use mine on the ocean and find my 470 just fine as is. Get's up and planes easily. I will need a very calm sea to run WOT for any length of time. Not once did my wife ever wish it had more power...

I am not a mechanic, and interested in your comment about removing the harmonic balancer. Is that risky? how much more power would one get?

thanks,

rkc
 
finally someone who has shown a interest in what im doing with where im using it it will be the sea but i took it for its first run on a lake cause i think they work harder it was doing 32mph at 4000rpm when the pushrods broke and there not a standard push rod there a 5/16 herden pushrod the only way for then to bend is hit a piston or the rocker to bottom out i could easily repair what i got but its a 1988 model and due for a freshen up well the theroy on most engines is one hp per cubic inch in mild performance so i hopeing 220 plus hp once i get it appart ill inspect it and see what i can upgrade with even the pistons will be changed to a thinner ring and if posible a longer conrod which give the piston a longer dwell time on tdc which means more tork i wish there was someone else here who had the same engine so wee could split the parts and cost ill keep u up dated not just biulding for big revs 5500 max so i say around 45mph
cheaper than putting a outbaord and i will have to run hi octane pump fuel but will still be cheaper than running a 2stroke sooryy with the balncer a bigger one would stop alot of harmonics and vibration if u r not using the old charging system there no need to use that type weel i no for sure when i strip it
look like it will be next week cause i have been limited with a bad back THANKS FOR YOUR INTEREST
 
aussie said:
finally someone who has shown a interest in what im doing with where im using it
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Don't misunderstand us Aussie, speaking for myself and I'm sure a lot of the guys here, we're very interested in your project. Lack of communication does not automatically mean a lack of interest. Rest assured, if people were not interested, you would not be getting the all the replies you have been getting. :head:
 
Destroyer said:
Don't misunderstand us Aussie, speaking for myself and I'm sure a lot of the guys here, we're very interested in your project. Lack of communication does not automatically mean a lack of interest. Rest assured, if people were not interested, you would not be getting the all the replies you have been getting. :head:
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yes your rite people have been great on here :clap:
 
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