Direct Injection 2 strokes

[Jabba_]

Thanks Jabba. Bugger about the tt units. As for propping how could they prop it for 5700 if they didn't trial different props on the yammy to get it on the plane first. I could theoretically prop an etec for a 28 footer stick it on and see it not get on the plane. I still don't understand the validity of the test. If the yummy was propped to get it out of the hole and then top speed was less than the etec cause the etec could get that hull on the plane in about the same time/distance I wouldn't be lambasting the test. Cheers mate

Scott, not sure what mean,, but to have both motors running at 5550rpm (E-tec) and 5600 (Yamaha) I dare say that no theoretical
estimates were made for the Yamaha's prop and the optimium rpm was reached at WOT with both motors powering the boat together and the props were trialed untill the RPM's were matched at optimium rpm's... By the look off the prop its a Viper, which is probably better then any Yamaha prop anyway..

[OPTI]

both engines were propped for recomended maximum rpm ,running together as you would do normally ,running them one at a time demonstrates the tourqe difference between the 2 stroke and the 4 stroke ,pretty simple really

[ozscott]

I get it - its a narrow test for twins showing that one has the grunt to get it to plane and one does not as propped for the twins set up. Of course for anyone wanting a single engine this is irrelevant because propping would be done to ensure performance down low and up high. As I said above I have no doubt that the etec has more grunt down low than the Yammy or any other naturally aspirated 4 stroke, but it was the way the test was done which I couldnt understand. I know understand it to a point, but maintain that top speed is utterly irrelevant and is just a marketing ploy - they could simply have said one planes the boat and one cannot. Of course if it was twin Yammy's on the back you wouldnt ever need to rely on just one .

Cheers