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Re: New Engine Option for the Mac
Posted: Sat Mar 20, 2010 6:00 am
by Dimitri-2000X-Tampa
Highlander wrote:Very nice indeed , did you know that Suzuki is the only O/B maker that race tunes all their O/B eng.'s thats why their so smoove !
J
What exactly does "race tune" mean? I would have figured it is extra cam shaft and additional valves that make it smoother. What about reliability and repairs? Some of you guys have owned these engines for years now so I was just curious if the repair rate is any higher with the additional complexity in these engines?
Re: New Engine Option for the Mac
Posted: Sat Mar 20, 2010 6:10 am
by Dimitri-2000X-Tampa
Duane Dunn, Allegro wrote:My Tohatsu 70-90 does not come anywhere near hitting the seat when raised. It's a much smaller powerhead than the Suzuki beast.

Hi Duane, I take it you are happy with your new motor and you have had it for some time now. What exactly does 70-90 mean? I know that the same block can support different HP's depending on how its tuned, but isn't yours one or the other?
Re: New Engine Option for the Mac
Posted: Sat Mar 20, 2010 9:29 am
by Highlander
Dimitri-2000X-Tampa wrote:Highlander wrote:Very nice indeed , did you know that Suzuki is the only O/B maker that race tunes all their O/B eng.'s thats why their so smoove !
J
What exactly does "race tune" mean? I would have figured it is extra cam shaft and additional valves that make it smoother. What about reliability and repairs? Some of you guys have owned these engines for years now so I was just curious if the repair rate is any higher with the additional complexity in these engines?
I have a 40hp 4/S suzuki on my

runs like a dream

for more info on their race tuned eng. O/B go to the Suzuki home site
J
More than I expected!
Posted: Sat Mar 20, 2010 9:14 pm
by vkmaynard
More than I expected!
After a 3 hours of breakin I was allowed to try full throttle for a short time. Unbelievable, 29.5 mph @ 5650 rpm with two people and 22mph @5050 rpm with ful ballast with a 13.75 x 15 4 blade prop! All GPS numbers. This engine is insaine and it's not fully broken in yet.
So it looks like I need either a 13 7/8 x 15 3 blade or the 13.25 x 13 4 blade prop to get to 6300 lightly loaded and 5800 rpm (max horsepower) with ballast. Should hit 30 mph with the correct prop.
The eingine ran much smoother after 3 hours of breakin.
Victor
Re: New Engine Option for the Mac
Posted: Sat Mar 20, 2010 9:43 pm
by Duane Dunn, Allegro
The 70 and the 90 are the exact same motor except for two parts. The 70 hp air intake has a insert in it that reduces the size of the intake hole and the volume of air it can ingest, and the computer modules are different. I have both sets of parts. By serial number my motor is a 90 and at this time it has the 90 hp parts in it. The sticker on the cowl however is a 70. Don't ask how I ended up with this franken motor, it's a long but secret story.
Re: New Engine Option for the Mac
Posted: Sun Mar 21, 2010 10:14 am
by Highlander
Re: New Engine Option for the Mac
Posted: Sun Mar 21, 2010 12:20 pm
by elvatoli
I'm planning to upgrade my 9.8 2 stroke Tohatsu for my 2000 MacX
The Tohatsu dealer wants $5800 (everything included) for a new 50hp 2 stroke, wich he said is the right one for this boat.
I dont know if this is the maximum power one with still a rope to start ?
I would like to have this starting option since I have been out of electric power in the past. I'm running 2 interstate 24 deep cycle batteries, but with a lot connected to it CD stereo, Depth sounder, Speed meter, Charplotter, Fish finder, 2000 W inverter , Fridge, Microwave oven, etc.
I would like also to have plenty of charging power from my motor to replenish my batteries.
And as everybody want to have the maximum possible power to attain the maximum possible speed without loosing control, and at the minimum price with the max warranty.
I'm thinking on the Tohatsu 90 since with is less weight than others and very reliable. My Tohatsu 9.8 have been working every time with any problem.
any ideas ?
Thank you
Hector
Re: More than I expected!
Posted: Sun Mar 21, 2010 12:32 pm
by Stefan
vkmaynard wrote:More than I expected!
After a 3 hours of breakin I was allowed to try full throttle for a short time. Unbelievable, 29.5 mph @ 5650 rpm with two people and 22mph @5050 rpm with ful ballast with a 13.75 x 15 4 blade prop! All GPS numbers. This engine is insaine and it's not fully broken in yet.
Victor
this sounds really good, first I fought there might be something wrong with my boat. But then I realized I should probably not try to compare numbers with your case with empty ballast, since 26M should be heavier then 26X due to permanent ballast.
I already found where I'd be able to order a 14x11 3 blade Hustler prop, but I wonder what would be the best choice in 4 blades, I suppose it should be either 13.5x11 or 14x10 on order to push through more water, but I don't know what brand makes these types of props for this engine, any thoughts?
Re: New Engine Option for the Mac
Posted: Sun Mar 21, 2010 8:26 pm
by vkmaynard
Something seems wrong with your setup. The M only weighs 300 more lbs. It's not a planing hull (not sure how that figures in mph).
All the props you are looking at would definitely over rev our motor.
The prop we have now is a Solas.
Considering the 13x15 4 blade and the 13.875 x 15 3 blade and the 13.25 x 13 4 blade.
Probably need to custom tune the original prop to 14" pitch.
Victor
Re: New Engine Option for the Mac
Posted: Sat Mar 27, 2010 1:00 pm
by Kelly Hanson East
Hector - a 50 HP four stroke is easy to start by rope. I cant speak about bigger engines.
If you want a bigger motor, you could possibly give up the hand starter in exchange for a starter battery (<100 USD) as a back up.