Originally Posted By Gambalunga
Perhaps we have someone on here who can explain why there has not been a similar legislation to that governing the introduction of unleaded petrol. Surely if the urea was included in the fuel you buy at the pump the whole issue could be resolved.


If urea was stable in the combustion phase, then it could be added exactly as you say (or we could all pee in our tanks - although the urea concentration would only be about 10% of what is required).

Sadly, the urea has to be added downstream of combustion, as a fine spray in the exhaust gas, upstream of the fine catalyst. The addition of urea converts the nitrous oxides into ammonia which is then converted in the catalyst to yield mainly nitrogen and water.

Stuart
"There's no skill substitute like cubic inches."