So, what did I do today? (Wednesday)

     Well, let me tell you. I decided that since there's 45,000 miles on the Morgan without air filters on the Webers (which is the stock setup), maybe I should give the old girl a break and try some air filters. I bought a set designed for the shorter horns I had recently purchased but was a bit disappointed that they likely would not effectively prevent fine dust like the stuff on the road near the rock crusher near Island View. I was introduced to some really neat accordion style circular ones meant for truck air compressors I believe. So, experimentation was called for.
     Since the Morgan Super Sport has twin Webers with two throats each, the result is that there is the ideal setup of essentially one carb per cylinder. So, for the experiment, I decided to leave two throats with no filters, one throat with the purchased screen type filter, and a temporary makeshift installation of the other type. This is what it looked like before the test run:

 

Makeshift filter, no filter, screen filter, no filter

(Click on any photo for enlargement)

     Now, time for the test run. I gave it a good chance to warm up, driving at a good highway speed, then shut off the engine and coasted to a convenient spot to check the spark plugs for the evidence. At this point I should mention that I was going to ask for predictions from the readers of this site as to what I discovered, but decided not to. What I discovered was this:

 

     That actually confirmed my suspicions, so the makeshift filters are definitely not going to be used. It looks like the screen filters were carefully designed to give the best filtering without cutting the air/fuel ratio. After having just completed a beautiful valve job with new valves, springs and guides, I certainly had no interest in ruining it with carbon buildup.

     Not finished just yet. To double check my findings, I decided to change the spark plugs so that a clean one was in the spot where the dirty one was, and visa versa and drive home and check again. Well, that nice clean plug looked like this by the time a got home:

Totally sooty black!

     Needless to say, I am glad that I didn't just install a bunch of unknown filters and drive around for a couple of thousand miles! Ouch! I did have fun 'cleaning out the engine' on the highway later this afternoon—without filters of course. 

- David