Green Speed

[David]

I have an Allison SS2000 with a Merc XR4. I would like to upgrade to a 'green' engine. My goals would be to increase acceleration, maintain or increase speed, burn less gas, and pollute less. I sometimes have to buy lake gas, so the ability to run regular fuel would be a plus.

I am interested in the 2.5L Etecs as these are lighter than the 3.3L engines. I think my SS2000 would be easier to rig and drive with a lighter engine.

The 2.5L engine comes as 150, 150HO, 175, and 200. Which would be best for me? The 150HO is not rated for HP, and comes with a high performance gear case. Would I still need a nosecone with this engine? Does it have solid engine mounts?

The other obvious engine choice is the Mercury 200XS. It has the sportmaster gear case and solid engine mounts. The drawbacks are more weight and the need for premium fuel.

Thanks

[stoker2001]

The other obvious engine choice is the Mercury 200XS. It has the sportmaster gear case and solid engine mounts. The drawbacks are more weight and the need for premium fuel.

ThanksMY 2006 250XS is ok on 87 octane as i thought all the 06 models were compatible for the low grade fuel now :confused:

[Lockjaw]

I would get the Merc, it has bee thoroughly tested.

[SUPAJAY]

I think the new 2.5xs would be the best choice. It is very fuel efficient and pushed a new euro over 100 with four people. Greg wrote an article on it.

[David]

from the Mercury racing web site

250XS and 225 both run 87 octane
the 200XS still needs 91

The bigger motors weigh 505 lb. I struggle with my XR4 on my SS2000. Another 100 lb off the transom would not make it easier to drive. It could work for someone, but not me.

Of course if the fuel econony was really good, I wouldn't need to refuel on the lake:)

[Jimbo]

I would get the Etec 200 motor. You pointed out the drawbacks on the 200XS Merc; The Etec 2.5L weights less and the Etec technology is simpler and better than the complex Opti technology.

You can always put a low water pickup on the Etec motor and getting solid mounts on the lower mounts should be easily enough to do.

I am running an Allison so I understand the problems finding a motor that will work with the Allison.

Jim

[Stinky]

the Etec technology is simpler and better than the complex Opti technology

Jim

Better?? How so??? :confused:

[C-Webb]

The Etec 2.5L weights less and the Etec technology is simpler and better than the complex Opti technology.
Jim

Not true.

[David]

I think only the factory engineers really know which is theoretically better, the Orbital based technology used by Mercury, ie Optimax, or the ETech.

The goals for a DI system would be

fine atomization (for better combustion)
high fuel flow rate (so we can turn more rpm)
mechanical simplicity (cost and reliability)
weight

Practically, Merc, Yamaha, and the Bomb have systems that seem to work.

[Stinky]

I think only the factory engineers really know which is theoretically better, the Orbital based technology used by Mercury, ie Optimax, or the ETech.

The goals for a DI system would be

fine atomization (for better combustion)
high fuel flow rate (so we can turn more rpm)
mechanical simplicity (cost and reliability)
weight

Practically, Merc, Yamaha, and the Bomb have systems that seem to work.

fine atomization (for better combustion) -- Merc wins hands down. Air assist = smallest droplet size. Thats why you'll always see Merc win the fuel milage shoot outs.

high fuel flow rate (so we can turn more rpm)-- I'm sure they all have high enough flow rates. High RPM is more about combustion chamber shape, piston bowl shape, plume containment and scavanging of the very deep head bowls. Merc ran the 200XS at Rouen 24hrs at over 7000 RPM and won. Advantage Merc.

mechanical simplicity (cost and reliability)-- Don't know about cost difference.
Time will tell on reliability.

:)

[David]

Bass & Walleye 225 shoot out

Max economy
Merc 4.6
Rude 4.0
Yammy 4.5

Overall fuel consumption was a wash between the Yamaha and the Merc
The ETec did burn more fuel.

Maybe counting displacement, the Yamaha HPDI is best. The Merc was a 3L, the other two were 3.3L

[Stinky]

Bass & Walleye 225 shoot out

Max economy
Merc 4.6
Rude 4.0
Yammy 4.5

Overall fuel consumption was a wash between the Yamaha and the Merc
The ETec did burn more fuel.

Maybe counting displacement, the Yamaha HPDI is best. The Merc was a 3L, the other two were 3.3L

Forget displacement, how about HP/speed. :eek:

:)

[150aintenuff]

ita an alli...which one is lightest for the hp????? that will be your new motor...

[Gusto1]

David, Definetly the E-Tec 200 although I would go with the 3.3l even though it is a tad heavier. The fuel & oil consumption is far and away better than anything out there. The E-Tec 3.3l 200 comes out of the box well within the certification boundaries which require the rated horsepower to be 10% + or - rated horsepower. They are actually at the top of the range of exceeding the power on the motor cover. They consistently will come in at 216-219hp. I have actually seen them pull as high as 226hp.

The hole shot will blow anything away regardless of weight, you're talking BIG TIME TORQUE!

The new 2.5l, if you can even get one yet is good but not worth waiting for compared to the 3.3l 200hp.

Like Jimbo said, the E-Tec technology is by far not as complex as the Optimax (Orbital) Technology. Low water pick-up & solid mounts are easy enough to do.

I was at Texas Boat World a year ago and saw 8 out of 10 of the Optimax's he sold on the bench or floor as junk!:D

[150aintenuff]

ETECH- LOTS OF TORQUE!!!!!!!!!!!!!!!!!!!!!!!!!!!!! OMG UNREAL... there is an SST Stoker around these parts and it turns a vented 15.25x30 bravo 1 4 blade... to the limiter loaded to go skiing.. 86-89 mph... holeshot is like RIGHT NOW as well....

[Gusto1]

Yes, No doubt, I believe it! You're talking over 500 ft.lbs. of torque down there. You could raise your ports & still have it! You know Greg Jacobsen up in Seattle at Sea-Way Marine?:D

[Michael Martin]

The reason you see the merc always faster is the books are the rpm limits. BMC, yamaha or suzuki have factory limits & recommended rpm ranges in the 5000 - 5700 range when the merc is 5500-6500 rpm. So same prop same boat the merc wil be faster as the publishers have to go by the recommended RPM range.

The 2.5 BMC 200 is made for lighter application wher the extra weight would be a problem. I have ran several 150 ho's & been very impressed with the 2.5's.

Mike