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Old 01-22-2012, 10:28 PM   #74 (permalink)
Ken Fry
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Quote:
Originally Posted by Old Mechanic View Post
Not to offend anyone here but the idea of injecting fuel directly into a catalytic converter to me is disgusting.
Thems is mighty strong words, pardner.

I agree that it would be nice to avoid the use of a catalytic converter, but the three-way catalyst was the start of a group of technologies that have permitted specific output levels from family sedan engines that are much higher than we used to get from pretty exotic sports car engines. Prior to emissions controls, we thought of 60 hp per liter as being quite good for a sports car, and put up with 10% of the fuel going out the tailpipe unburned. Now essentially nothing other than water and CO2 comes out the tailpipe, and we get 75 HP per liter from family sedans. None of the old engines were more than 25% efficient at peak, but now the Prius is 37%.

While it seems counterproductive to inject HC into the converter, that is essentially what we have been doing for a long time with spark ignition engines. Injection typically dithers between 1% too lean and 1% too rich in SI engines: whether it actually passes through the cylinder makes little difference. I'd say it's an unfortunate fact of life, or perhaps ironic, rather than disgusting.

But I agree, the Transonic system sounds pretty good.
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