Tohatsu Need For Speed

[BlackKnight755]

I have a 1997 50 hp Tohatsu with power tilt and trim, mounted on a 14 foot john boat. I have boyesan reeds, and I also have a 1-of-a kind exhaust tuner installed. I currently run a 15 pitch SS prop at 6000 RPMs easily. I would like to know if any one knows where I can get any after market go-fast goodies for an engine this small. If you have any suggestions, about anything, lease post... Thnx in advance.

 

[Johnshan]

Re: Tohatsu Need For Speed

Did you notice any improvment with the reeds? I want to do the same to my motor (Add the reeds), how did performance change when you added these? Thanks a lot. My motor is a 30hp Mariner so my perf. may be diff.<br />-John

 

[Johnshan]

Re: Tohatsu Need For Speed

Did you notice any improvment with the reeds? I want to do the same to my motor (Add the reeds), how did performance change when you added these? Thanks a lot. My motor is a 30hp Mariner so my perf. may be diff.<br />-John

 

[BlackKnight755]

Re: Tohatsu Need For Speed

John,<br />The difference after the reeds were replaced, was not real noticable, until after I started doing some other modifications. But from personal experience, EVERY motor is different. example: One of my good friends bought a tohatsu 40 hp at the same time that I bought my 50, the engine is the same exact weight, bore, stroke... everything is the same except carb is bigger on my 50 and timing is different. He purchased a set of reeds at the same time that I did, and he realized a VERY big difference compared to my initial power gain. I have also heard from other friends that have the reeds changed in there motors that the smaller the motor, the more that you can tell a difference. <br /> I installed the reeds for two reasons though, I must tell you that as well as the added performance, I was looking at the damage of breaking a stock stainless steel reed and having it go through my motor at 6500 rpms. If the boyesan reed breaks, it is not going to hurt the inside of my engine, as it is carbon fiber and plastic. <br /> Maybe this has answered some of your questions, feel free to e-mail me, BlackKnight755@hotmail.com, I may not know the answers, but i can get you in touch with someone who knows... See ya' later.

 

[BlackKnight755]

Re: Tohatsu Need For Speed

...Ok gang, I know that some of you guys out there have got to know some hot rodding secrets, or maybe know someone who has a little bag of tricks... I took my boat to the river on the 4th and some of my buddies were able to stay with me, and they werent able to do this a while back, so either they are getting faster or I am getting slower. Please help me to unleash some power from my little rice burner. Thnx again.

 

[evin300]

Re: Tohatsu Need For Speed

More performance orientated: http://www.bassstore.com/cgi-local/ubb/Ultimate.cgi

 

[evin300]

Re: Tohatsu Need For Speed

Even more performance:<br /><br /> http://forums.screamandfly.com/

 

[BlackKnight755]

Re: Tohatsu Need For Speed

Thanks Evin, I went to these sites, but I was unable to find many things for my motor. I am hoping that someone will post a site that deals with small motors, not the big v-6's, I am looking for ANY performance parts for my engine, new or used... Thnx for everyones help. BK

 

[BlackKnight755]

Re: Tohatsu Need For Speed

Well, here I am, still begging for any help that ANYONE can or will give me on my quest for getting all that I can out of my motor. I am having trouble finding sites that even list anything for thew small motors other than props and maybe reeds. PLEASE, I really need all the help that I can get, I still have that "NEED FOR SPEED"

 

[evin300]

Re: Tohatsu Need For Speed

Did you post on scream and fly? Many racers frequent the boards, some of them are from the days when you made your own parts, maybe some of your motors are used in certain classes of outboard racing? If ya want to go fast, ya need to hang with people that live it and breath it.

 

[JB]

Re: Tohatsu Need For Speed

This is against my better judgement, BlackKnight, but you have aroused the racing engineer of over 40 years ago. Back then kart racing was in its infancy and creativity was the order of the day. There was no such thing as an over-the-counter speed part. We invented them. We made them ourselves or adapted them from some different engine or application. It was like hot rodding in the thirties. I remember one 6.1 cu. in. engine that dyno-ed at over 30 hp (12,500 rpm). That is FIVE hp per cubic inch.<br /><br />We could have made your Tohatsu scream to 150 or more horses, but at a price. The price was part money, part reliability and part flexibility. I'm not talking a little bit of each, I'm talking a LOT of each.<br /><br />First: and this is the hardest part for most aspiring hot shots, you must UNDERSTAND, in exquisite detail, how your engine works.<br /><br />Next: Understand, in exquisite detail, how other high-output 2 stroke engines work.<br /><br />Then: Modify and adapt your engine to utilize the best features of all of them, including: kart, bike, glo-plug, outboard, snomobile and aviation applications.<br /><br />Good luck. You will probably need it.<br /><br />Red sky at night. . . . <br />JB

 

[MercilessMike]

Re: Tohatsu Need For Speed

Against my better judement, because JB has told the truth, the whole truth and nothing but the truth. But you must be young and have no place else to blow your money. (beats buying drugs) So this is what I can say to "your need for speed".<br /><br />Take off the head and have it milled about .030- .050, remember clearances!! then cc the chambers to match.<br /><br />Bore the cylinders and replace pistons, trim the skirts on the pistons also, (remember to hand grind your rings for a nice tight fit!) then have them balanced.( the assembly, crank, rods, pistons...) Get the rods shot peened and polished. Next yank the crank and send it to Falicon crank service in California, tell him to lighten it about 20 %. Next have the flywheel lightened, or go to an aluminum flywheel and a total loss ignition system, Now you need a battery! Then have the exhaust ports raised and polished, have the intake ports knife edged. Then polish the inside of the case. also have case decked and align honed. Get a big Ole mikuni carb and run Union 76 racing fuel. <br />Your on your own as far as props. <br /><br />Take your GPS with ya, cause your only going to get one shot at your need for speed. <br /><br />Far cheaper to get another motor and put Tohatso decals on it to fool your friends!!!<br /><br />YO HO HO and a bottle of Rum !!

 

[Dunk]

Re: Tohatsu Need For Speed

This is really a waste of time with that boat. A flat bottom jonboat, the harder you push it the more it sucks down to the waters surface. I think you would see better speed if you went to 17" prop. Twisting that engine over it's rated 5800 is just throwing HP to the wind. A 17" would keep her down in the 5500 range where the engine was designed to make her HP.<br /><br /> Setup would the next thing. Have you tried lifting the engine to see if that improves speed? What props have you played with?