It seems you can change a Tohatsu 8 2 stroke to a 9.8

[boatster]

I was just looking on the Tohatsu website and they have the 8 and 9.8 under the same manual. I wonder what is required to upgrade my Tohatsu 8hp 2 stroke. <br /><br />Hi Elvin, are you sure its not possible to upgrade an 8 to 9.8? <br /><br />The displacement, stroke, and bore are the same as well. <br /><br /> http://www.tohatsu.com/tech_info/own_man_pdfs/8_98.pdf

 

[TOHATSU GURU]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

Different block...Same cubes, but different porting.

 

[boatster]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

Do you mean different porting as in the exhaust or intake? I'm just curious. Thanks.

 

[TOHATSU GURU]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

That's a good question that I don't have the answer to. I'll ask a tech geek tomorrow and find out....The blocks have different part numbers and all the other parts on the engine are the same.

 

[TOHATSU GURU]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

Both the intake and exhaust ports are different. So says the tech guru.

 

[boatster]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

So they're bigger? Of course there would be know way I could modify the block to get that extra 1.8 hp. Thats too bad. It seems the motor peaks out at roughly 1/2 up on the throttle. It just seems like theres more it can go. Oh well. Thanks for looking into it Elvin.

 

[TOHATSU GURU]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

Not bigger, just cut different. But, that 8 should wind all the way out. It may be a little sick.

 

[boatster]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

Sorry, I meant bigger intake and exhaust porting on the block. Well my motor gets the sib (10' Avon inflatable) up onto plane and going quite fast with two people and a bunch of gear. It runs nicely and all its just the throttle doesn't seem close to linear with respect to acceleration. Seems to top out relatively early on the twist grip but we're still cooking along nicely, 18mph on the ocean. It might just be my perception too.<br /><br />I must say I do love this little motor though. So light and reliable.

 

[TOHATSU GURU]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

Might be the prop. The next time you need a new one drop down an inch on the pitch.

 

[boatster]

Re: It seems you can change a Tohatsu 8 2 stroke to a 9.8

Thanks Elvin,<br /><br />It could be the prop. I'll probably have to live with it for awhile.