Motor Info

[Minihawk]

I have a 95 Rude 30hp, Dose anyone know the lower unit ratio? I am running a 18p Mini Merc Chopper and I was told I could turn the motor 6000 and be safe. I have noticed people doing the math and coming up with a top speed. Just wondering what mine should be. I can only get 29 mph on the GPS, is that just all it should do or is the prop just slipping? Should I even try to hop up this little 30 or just repower. Wieght is a big issue, the rude weighs in at 127lbs. Dont know that I could go much more. What could be done to get more power out of my little rude? I have noticed that the 40hp rude has the same bore and stroke, how is it making 40hp? I am new to this and I love it, this boat is like my training wheels. Just hoping to learn something so I can move into something faster.

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3574

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3575

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3579

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3577

[Minihawk]

TTT Any Small Motor Gu Ru's ???????

[bow2no1]

i don't know what the ratio is.
seems like she should do more then 29 mph.

try finding out if a set of carbs will fit from a 40 you may need the intake as well for optimal performance. i have my doubts the prop is slipping. once the hub starts to go it doesn't take much to totally burn it out. how many RPM's is the motor designed to go? what the peak RPM? you don't want to rev past your peak.

[Minihawk]

It has a single carb set up, I dont know if the 40 is a bigger single carb or what. When I said the prop was slipping I ment cavitating. The hub is fine it's new. It seems as if its just not hooked up good??? I was told I could turn this motor 6000 rpm and be safe. I played with the engine height and its as high as I could go and still get on plane. I've made a ton of tab and motor height adjustments and the best I've got is 29 mph. Just kinda stuck here.???

[bow2no1]

6,000 might be safe but it it at the peak of your torque curve?
if your peak is 5,500 then your past you peak and it's not doing you any good to go over that. most engines rev past their peak.

i think the 40's are dual carbs.
like these on ebay http://cgi.ebay.com/ebaymotors/EVIN-JOHNSON-40-50-55-60-HP-1994-CARBERATOR-SET-NICE_W0QQcmdZViewItemQQ_trkparmsZ65Q3a12Q7c66Q3a2Q7c39Q3a1Q7c72Q3a1171Q7c293Q3a2Q7c294Q3a50QQ_trksid Zp3286Q2ec0Q2em14QQhashZitem20ac5d4172QQitemZ140330746226QQptZBoatQ5fPartsQ5fAccessoriesQ5fGear

maybe if you had the intake you could make it work?

or find a single motorcycle carb or something to adapt thats larger you might get a bit more power out of it.
also you could probably find someone with bridgeport and mill 30 off the head that helps too, i have done that a few times.

[Minihawk]

Yea I need to find a good cross over motorcycle carb. I will do some reserch. I will also keep a look out for blown 40 so I can maybe get some parts. I have no idea about where the tourque cure is, I may be reving into the flat part of the power band. I'm sure someone out there has raced a small 2 cylinder rude. As for the bridgeport thats no problem I'm a Machinists. I can do the head work. Just need to work up the nerve, its always easier when its someone elses stuff. lol.:D

[samari]

The 40 does have twin carbs, that would be a lot less work than a motorcycle carb.

[bow2no1]

here is an intake.
http://cgi.ebay.com/ebaymotors/Cylinder-Block-Evinrude-Johnson-40-50-hp-1990s_W0QQcmdZViewItemQQ_trkparmsZ65Q3a12Q7c66Q3a2Q7c39Q3a1Q7c72Q3a1171Q7c293Q3a1Q7c294Q3a50QQ_trksi dZp3286Q2ec0Q2em14QQhashZitem27a9c47224QQitemZ170351948324QQptZBoatQ5fPartsQ5fAccessoriesQ5fGear

[Minihawk]

Thanks for the ebay find, I asked the seller if he would seperate the intake and the block. We'll see what he says, I found out that my gear case ratio is 13:28 dose that sound right??

[bow2no1]

for the price he's asking almost worth it just to buy it and ask him to to ship just the intake. maybe save on shipping?
i dunno about the ratio.. i have only done some lobster boat racing and some some of the smaller skiff classes for fun. they are generally work boats raced on weekends.
ratio's wasn't really my concern. i'm looking now for some fresh water races maybe up to to drag my G3. hopefully in good time i will get in to ratio's as the situation presents it self.

[jody504]

The 40 is a looper and the 30 is a cross flow the intake would not even be close to fitting the 30 goes into the cylinder as one peace with a reed plate that is flat the 40 has two seperate reed block that mount to the carb plate. They do have alot you can do to the motor you have. The 40 is a better motor only because you can get alot of part that will fit off of the 40,50,60 and the 45 ss part do fit

[Minihawk]

Thanks alot for the info, that saves me time and $$$. You say I still have options for my motor. Whats your opinion on my 30 should I just leave it alone and play with my setup. It sounds like it maybe easier to just try to find a 40. It really sounds like you know your small rudes!! Thanks again!!

[jody504]

They have a few people that play with the crossflow and make good power. The 40 is a more bolt on extra motor you can build more power out of a 40 with parts that can be found easy on ebay and the board from time to time. we had a boat like your a long time ago that belonged to my boss at the times son had a 25 on it it was fun to play with but when we put the 45ss on it it was a handfull and ran above 70. The motor you have can make good power but you would have to find someone that want to do it and know what to do crossflows have alot you can do to them but they are geting to be oldschool alot of people don't mess with them.If you want to get into taking it apart they do have a few things that can be done and easy to do but it would have to come down to realy get alot out of it smaller h.p.engine are more setup than making more power. The ports and all can be done if done right it will bring more power but 10 h.p. is easy to bolt on.

[Mark75H]

What boat did the 45ss run about 70?

[jody504]

It was on a panterua hull we called Darish Allison and he gave us some tip on how to do the bottom. The boat ran great to about 65 then it was all the driver could handle.I at the time was not that guy Todd at evoulution was the little man that could make it fly he was about 12 and put everyone that got in it to shame.That was back in the late 80

[flabum1017]

The two cylinder looper 40 is a good motor....they used the same block as high as 60HP stock......

[Minihawk]

:)What is a 45ss?? Is this a race motor?? Whats the weight??:thumbsup:

[Capt.Insane-o]

There is'nt a whole lot you can do to the thirty to make a significant amount of power. It has nothing in common with it's larger brothers. A motorcycle carb is a waste of time. I'd look for a decent used 40-60 twin with power trim and go from there. In stockish form they will push you as fast as you want to go in that hull with no reliability worries and you'll have a pretty broad prop selection.

[Minihawk]

That sounds like a plan, I have been looking and not had much luck. I have found several 40's but they were triples and to heavy. A 40 twin with power trim is hard to find. I would also like a 40 merc. with P/T it seems like they have some hop up parts out there. Untill I find something I will just keep playing with the boat how it is.

[Capt.Insane-o]

Your not going to find any hop up parts for mercs untill you get to the v-6's. Due to their design they are what they are. Good running motors, but not feasably modified. Another good choice would be the 40-50 tripple yamahas

[bow2no1]

i know where there's a 32hp yamato, the guy sold the boat a few years ago.
i dunno if it's for sale or not? he clims it has the torque of the 60hp and make is 10' go over 60mph.

[Minihawk]

I have a Yammy Pro 50 with P/T it has less than 25 hours on it. It came off a friends pontoon, he bought it new and then wanted more power. It has been in my dads shop for years. It wieghs almost 100 lbs more than my 30. My Mini Hawk will not float it. It needs a good hull! Something small and light. I would like a 60 mph small boat.

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3647

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3649

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3650

http://forums.screamandfly.com/forums/picture.php?albumid=508&pictureid=3651