Ride on 18's with brackets?

Bushwacker · #1 03-31-2011, 11:25 PM

Quote:

. . . I have never owned a mercury but it seems that the optimax 1325 might be a suitable modern engine replacement. . .

??? That sentence makes sense if you meant to say optimax125!

Snookered has had personal experience with 3 different 18's with 3 different motors on them (130 Yam, 150 60 deg OMC V-6, and Zuke 140 4-S), so he knows that boat and it's sensitivities better than any of us! I think he summarized it well.

I would suggest you might want to also consider the 90 hp DI 2S motors as well. That gets the weight down to around 350 lbs, which would be real desirable if you wanted a bracket, and they'd burn even less gas! Most folks don't realize that the VDH hull design is at least 10% more efficient than any other deep V, so you don't need as much power on a SeaCraft as you'd need on any other similar size hull! Fr. Frank is getting great performance out of his 90, and BRP is sandbagging on the E-TEC HP ratings by as much as 10%! The HP curves for both the 150 and 225 E-TEC's have been published in factory literature; the "150" is actually 165 at the prop and the "225" is actually 240, so that 90 hp motor might surprise you! Windrider just put a 90 HP E-TEC on a 20 cc, so we're all waiting to hear how that turned out!

asdfhood · #2 03-31-2011, 11:36 PM

Sorry for the typo. I meant OptiMax 125. The OptiMax 75-125 all use the same 1.5 L block and are advertised to all weigh the same. Therefore i thought it best to opt for the 125. More power and the motor would not have to work as hard.

Bushwacker · #3 04-01-2011, 12:19 AM

True, but sometimes the higher output models are tuned/optimized for higher rpm to get the extra hp, and may actually have less torque at lower speeds where you need it to get on plane, so the "more is better" thinking isn't necessarily correct. Depends on the application, so need to think about how you really use the boat and not just top speed!

The 90 hp E-TEC is a 3 cyl/1.3L engine (1/2 of my V-6) that weighs 335 lbs w/25" shaft, with 2.25:1 gear reduction, so it can swing a big efficient prop.