Verado 275 - 400hp ??

[CUSTOM PERFORMANCE 1]

A couple of thoughts,
I believe Mercury built the Verado to give back the torque that is missing on the new 4 stroke outboards of today. I have run a few and they are truly PIGS compared to equal power 2 strokes. The problem is that our wonderful government has mandated these epa figures that the manufacturers have to meet to stay in business. I have run a Verado and it is really a work of art for a fishing motor, nothing compares. As for boosted engines, my little 1.1 liter homda Blackbird makes over 260 hp at the tire on 9 lbs of boost on 93 octane pump gas. It is completely reliable with a 10.5 to 1 compression ratio. If you do the math, that is well over 200 hp per liter! However, outboards are subject to constant and extreme torque loads and in a boosted motor that builds heat quick. So to make it reliable, they use fairly large displacement engine on relatively low boost levels to achieve reliability, especially when some numnut will fill the tank with 87 octane fuel cause that is all he could get. And I am sure they are not cheap to repair.

[John1250]

400 hp? The best thing about it is : Cut it in half, use a light weight mid and LU and get 200 hp out of a 325 lb 4 stroke with good low end torque. Oh yeah, half the cost too??!! Seriously, I think the Verado flunks only one test of engineering - Make it simple. A supercharged 4v 4 stroke w/variable valve tuning involves a lot of moving parts. All parts have to be engineered with respect to hardness, flexibility, strength, lubricity, heat characteristics, heat transfer, etc. Not to mention servicability, cost, diagnosis, etc. Boy I gotta think the the more appropriate route would be to start with a two stroke and not waste half the piston movement just to pump gasses in and out of a cylinder against little resistance. A turbo two stroke could scavange gases as well as a 4 stroke and the turbo is driven by only exhaust gas expansion, creating a little desirable back pressure.

[sho305]

How about a 4 cyl from a 300X? Ah well, we will have to see how the 2.5XS does.

[optimax135]

I don't know what for set up you ran the Verado but to call them pigs is kinda harsh. All the verado's I ran matched or out performed the 2-stroke(factory motors). I'm not sure where you are coming from with this. Why would Merc market a motor that wouldn't match or meet the performance requirements of us boaters? Personally I was quite impressed with the performance of the Verado.

[300x Stoker]

Stevens is our local dealer. I just called them to find out the scoop. They have 1 Verado they are rigging on a boat and are waiting for the controls to be sent. They don't have any more to sell now. It will be one more month till you can get one.

[blkmtrfan]

Thanks for the info about Stevens, I ran into that list and it looked like they were selling them, would love to see on run in person

[CUSTOM PERFORMANCE 1]

I meant I have run a number of new 4 strokes and they are pigs. When I ran the Verado, I was most impressd, nothing like it on the water today. This is a production fishing motor, aimed at the general boater and offshore fishing guy that wants 2 stroke performance with 4 stroke economy.

[1BadAction]

Originally posted by John1250
Boy I gotta think the the more appropriate route would be to start with a two stroke and not waste half the piston movement just to pump gasses in and out of a cylinder against little resistance. A turbo two stroke could scavange gases as well as a 4 stroke and the turbo is driven by only exhaust gas expansion, creating a little desirable back pressure.

woa woa, hold your horses, im working on it...

[sho305]

mmmmmmmm, Turbo....

[1BadAction]

yep, This one has .800" dia impellers for my RC stuff. It worked awesome untill i tried to run it TOO close to the exhaust port and melted the ends of the aluminum blades to the case so the next turbine impeller is going to be titanium...

I am also going to be making 1.5", 2", 2.5", 3", and 4" models for other applications. each size of course is going to have several different impeller pitches to alter the boost level. The bigger stuff it going to be Cast steel cases, with machined insides. Which, finding a place to do this has turned out to be a pita. this small one is made of billet 6061-t6 aluminum parts, and the turbine is 6al-4v TI

[1BadAction]

dont want to let the cat out too bad, but heres another showing the exhaust.

[Mark75H]

What lubricates the bearings?

[1BadAction]

there is alot of stuff that i hand drilled and tapped on these prototypes, and the models dont show them. in the center of the bearing housing, there is a pressure nipple in the top, that has a length of tygon that connects to the bottom of the turbine housing where the unburnt oil and fuel collects. that gets rid of the puddling problems, AND lubes the bearings. the bearings are boca bearing ceramic units with teflon seals, I remove the seal on the inside so the oil can get to it. and leave it on the outside where the impellers run so it doesn't blow through too much. there is no blow by on the compressor side because the pressure pushes the seal against the bearing, on the turbine side it just goes back where it came from if there is any blowby.

[Mark75H]

Talk about simplification!

Brown oil from the turbine housing doesn't eat up the shaft?

Cool beans!

[1BadAction]

really, the full synthetic that i use for oil doesnt get gritty, the castor works just as good, but after you run it MUST be cleaned with motor spray, or it will get all gummy. simple, yes, you should see how i got the gravity feed carb to work