Dyno Test Outboard Drag Motor- Power Performance Engineering

[MrGarbezzy]

I thought the merc 2.5 drag motor had lyk around a 10,000 rpm chip in it. I kno the offshore motor had the 7,500 chip.

[makulaf]

@MrGarbezzy i think the ROS motors were 8200, and the drags were north of 11,500. brendan put one of his champ motor boxes on it for the dyno test.

[BulletBlazerSS]

with 33cc heads are you still running 93 octane?

[makulaf]

bullett, it was not my drag, and brendan Power did the dyno test so I cannot say for sure the octane. However, it is my understanding that with the 2.5's, 33cc will put you right at 145# which is still safe on 93 as long as you know you have good 93 octane. I run 34's on my 260 and 93 and have never had a problem.

[eddiesautoworks]

Wow - a real buzzbomb!

[originalbrownirish]

ball bearing

[150aintenuff]

so what fuel??? sounds clean...

[skirace]

that is totally awesome mate ... check out my sst140 on my skiboat at idle

[originalbrownirish]

so i"m assuming that the pressure built up in the crank case squeezes the oil in between the bearing surfaces right?

[camthrop]

That thing sounded great, outboards have lots of potential for big horsepower. The new Verado's were built so they can be tuned to push out horsepower in the 600 range while doing 12,000 RPMs! I'm still a 2-smoke guy though...

[makulaf]

Basically, the fuel/oil mixture is drawn into the crankcase through the reeds by the vacuum created during the upward stroke of the piston. During the downward stroke the reeds are forced closed by the increased crankcase pressure. The same pressure during the stroke forces fuel/oil into the cylinder which also forces out exhaust.

[originalbrownirish]

two stroke cranks or most 2 strokes don't a deaicated oiling system.

the only way i think it can recieve oil is, if its blown through the bearings which means they must have a relativly loose fit.

[originalbrownirish]

thats a 2 stroke right?

[makulaf]

yes. Mercury 2-stroke 2.5 Drag motor.

[smithkart]

looks like a Fish and a Parker squirt in this video!