Re: 150 Yamaha HPDI VS 4 STROKE
We installed a set of 250 HPDI's and ran them today(awsome). You can't compair them to a four stroke not in 100 years.
That's because Yamaha doesn't make a 250 HP 4-stroke. The biggest Yamaha 4-stroke you could compare that to, would be the 225 HP.<br /><br />
On the larger boats four strokes burn the same amount of fuel. That the facts forktree.
Well, you better explain your "facts" a little better. Because I can show you several published performance bulletins on the exact same boat that show you're talking trash.<br /><br />Besides, the only HPDI's that come in shaft lengths long enough for the larger boats (30") would be the HPDI 250 and 300...two horsepower models the 4-strokes don't come in.<br /><br />
First of all, if you're comparing Yamaha's 225 HP HPDI to their F225, you're comparing a 20" shaft to a 25" or 30" shaft. So that comparison is bull. If you need a 30" shaft (which most of us do with bigger boats), you can get it in the F225, but in HPDI you'll have to jump up to the 250 HP to get the 30" shaft. And that HPDI will only be about 40 pounds lighter. And you're not adding in the weight of the oil reservoir, and the extra fuel capacity you'll need, etc on the HPDI's either. The HPDI 200 and F200 might be a better example with the exception that the HPDI 200 is based on the same engine as the smaller HPDI 150, and the F200 is based on the same engine as larger the F225...if you get my drift. <br /><br />
you can't find the correct props for four strokes.
Please. You must not realize the HPDI's have a different gear ratio than the F's.<br /><br />
The 225 makes 218 hp on the dyno. They turn up more(RPM's).
My local shop clocks the dyno of the F225 at 229 HP. And the higher RPM lets the outboard take advantage of running a higher gear ratio (lower gearing, more thrust, bigger props, etc.).<br /><br />
Maybe on alittle lake on the big pond the real men Run HPDI's (two-strokes).Four strokes need more service.
How about on the
ocean where "real men" are nothing more than at the mercy of God? And HPDI's have never had a better service history than 4-strokes, sorry. Just take a look at the warranty difference. Maybe that's why you won't find one charter boat running HPDI's up here.<br /><br />
If something weights 100 lbs more how can it be the same.
It's not the same. With the added weight you get a pressurized lubrication system, better economy, less noise, less smoke, a better warranty, better re-sale, and most of all better reliability and durability. <br /><br />
Oh they require more maintance too.
And what "more maintenance" would that be? Changing the oil once a year? You'll spend more time and money changing spark plugs and messing with the oil reservoir on the HPDI. That's if you can keep it out of the shop.<br /><br />vinney, my Yamaha dealer is the largest Yamaha dealer in America. That's right, the largest.<br /><br />They stock a few HPDI's and will special order one if you want, but 4-strokes are what they primarily sell. In fact they sell more carbureted 2-strokes than HPDI's. And for good reason. The HPDI's haven't proven as reliable and durable as the 4-strokes, their break-downs are usually catastrophic, their warrantees aren't as good (gee, I wonder why), and they don't start and run worth a crap in cold water climates. Most of all, they just don't last as long.<br /><br />Give Factory Yamaha a call and ask them which outboard is better. I did. And they were right.