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Optimax, HDPI, Fitch, may be a thing of the past for 2 stroke engines.
According to the article below, in the future you be able to put a $400 part on the exhaust system of a 2 stoke motor and meet all the CARB emissions standards.
Researchers at the US Department of Energy's Idaho National Engineering and Environmental Laboratory, have invented a small separator that will remove unburned oil and gas from the two-cycle engine exhaust without compromising engine performance.
Small gasoline-powered two-stroke engines are used in many applications from recreational motor craft to hand-held power tools, mopeds, street motorcycles, and even low-cost automobiles. The engine is popular because it is lightweight, low cost, powerful and exhibits quick throttle response.
The two-stroke engine, however, is notoriously dirty. An unavoidable feature of the engine is that it requires oil mixed with gas for internal lubrication. During operation, the intake and exhaust ports are momentarily open at the same time, thereby pulling some of the intake stream containing fuel and oil to leak out into the exhaust port. This results in inefficiency and smoky exhaust emissions.
Typically, 25 percent to 35 percent of the fuel that enters the two-stroke engine leaves unburned. The solution to both problems, according to INEEL researcher and lead engineer Terry Turner, is a technology that can be implemented in new vehicles and retrofitted to existing ones.
The separator will take the exhaust gas and spin it at a high rate, thereby centrifugally separating the heavy oil, fuel and particulates from the lighter gaseous combustion products. The heavy constituents will be burned in an afterburner or captured and removed for recycling or disposal in an environmentally acceptable manner. Turner feels confident that a significant hydrocarbon emission reduction for standard engines, and per unit retail cost under $400, are realistic.
The uniqueness of the INEEL technology is the separator and its location. The separator is predicated on an innovative design. The separator will be located in the exhaust system, the muffler exhaust area, or a combination of both.
The separator also may reduce noise. Installing the separator inside the existing muffler or exhaust system would be equivalent to adding additional baffling.
"It's possible to build an engine with less exhaust, but it will be more expensive and, therefore, less marketable than current designs," said Turner. "Current manufacturers of two-cycle engines have begun aggressive research in cleaner engines in order to meet the new EPA guidelines; however, in most cases, the simplicity of the engines is being lost, and in some applications being replaced by lower performance, heavier four-cycle engines."
The best solution, said Turner, is a separator that can be put to use in new engines and retrofitted to existing ones.
"The two-stroke engine is a great product with vast applications because of its simplicity and light weight," said Tuner. "With achievable targets for emission reductions provided by the EPA, it's now time to provide a workable solution to the emission problems that have plagued the two-stroke engine since it was developed in the 1940s. We feel we have that solution and look forward to moving to the next level of its development."
Since he thinks that two stroke engines were developed in the '40s...he doesn't have a clue.
Everything in use is Grandfathered and exempt from EPA regulations up to the new product offered for sale in 2006 and beyond. Am I going to put one on my 1963 18hp, I don't think so! The direct injected 2 stroke is cleaner than most 4 strokes at this point. Evinrude's advanced E-TEC 2 stroke due in October is further advanced beyond all available engines now. With no regulations to require any change on pre-2006 engines, and all engines meeting the required rules on 2006 models, as many do now, where is the market for this "INEEL". Engines will be computor controled for great efficiency. No manufacturer is going to make a "dirty engine" and licence something that saves sluge.
Backfire
The direct injected two strokes are meeting 2006 environmental emissions specs. The author of this article doesn't have a clue. In fact the direct injected two strkes get pretty close to the 4 stroke fuel economy.
Actually some of the direct injected 2 strokes already meet the California 2006 and 2008 specs right now and emit fewer emissions than the fuel injected 4 strokes.
The Evinrude ETECH motors are said to meet 2010 specs including carbon monoxide which the 4 strokes will need a catalytic converter to meet.
We all know that we are more interested in saving gas/money than we are in saving the environment; right? Well, maybe not all of us, but the allure of the D.F.I. engines is the fuel savings. A catalytic converter of sorts that could be retrofitted to old two strokes would appeal to who? It doesn't hurt performance but it doesn't save any fuel either. So who's willing to pay $400.00 for one? I wouldn't invest much in the stock.
Tom Marlowe, sales at Summerville Marine. Past Master Tech.
My 200 hp optimax burns about six gallon per hour.DFI I think is here to stay.Computer control is the way to go for emission control,fuel economy and performance.
I think the consesus is correct on the boat motor issue, but I haven't seen too many HPDI weed- eaters. Like the article said, there are alot of items out there that utilize a two stroke motor besides boats.
How can dfi engines ever approach 4 strokes for emission control? My hpdis sip oil compared to carbed engines 10 yrs ago but I still burn 5 gallons of yammalube a day and a 4 stroke burns close to 0, right?
Emissions that the EPA is concerned about are oxides of nitrogen (NOx), hydrocarbons (HC), and carbon monoxide (CO). 4-strokes are low in HC (when new, but they increase greatly as the motor wears), but high in NOx and CO. A DFI 2-stroke is higher in HC ( but that hardly changes as the motor wears), and low in NOx and CO. Just like with your car or truck, the emissions are a total of the 3 byproducts of combustion.
Look at an EPA sticker on a 225 Yamaha 4 stroke, it shows higher emissions than a DFI 225 Evinrude. A 250 Evinrude is even less than the Yamaha.
Great idea--at least it would have been five years ago, before the manufacturers put all the time and $$ into clean 2-stroke development. Sorry Bud, you missed the ball.
What makes this all ironic is, there are more lawnmowers whether 2 stroke or 4 stroke out there than outboards! Lawnmowers have no pollution devices or leaner burning technology applied. I would bet that from the volume of lawnmowers out there that the volume of pollution is greater from them than from all the outboards combined. Yet no one is calling foul ball here!
it is simple. when you dump a couple of gallons of dfi oil in the reservior you dump the recycled garbage right back in the empty 2 stroke oil jugs! you could probely sell it to the guys who premix. it would bring the cost of dfi oil down a bit.
Optimax, HDPI, Fitch, may be a thing of the past 
