Lynn,

   As usual an education about the rotary......Please clarify for me the statement

below.....I presume the "18" is timing degrees BTDC and the "5" is the degree

split between leading and trailing plug firing ? Do you run a split on your race

car ? I presume you know that Tracy's EC2 has essentially no split.......What

is your take on the use of a split for our A/C use ? 

 

--
Kelly Troyer
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold

The split helps burning in slower leaner situations in street cars and on race cars that have to use stock or nearly stock induction systems. A few extra HP are available down low when this is done, and the idea of selling cars in the peoples republic of California is still appealing to Mazda so it is used to help with the unburned hydrocarbons problems the rotary still has.

 

There is no detectable (on the dyno) value in split timing in steady state mid to high RPM use, so the added complexity is of no value. In the race car where space is not a factor, I use the stock electronic distributor and trigger both MSDs from the leading pickup coil.

 

The distributor has no advance curve at all so the start, idle and race advance are always 24-27 degrees. Remember the 3 to 1 rule for rotaries and that starting timing would be like

8-9 degrees in a piston engine. So it is no longer an amazing number.

 

This is not Wankel's engine. NSU discarded his design and had to induce a compressor company to give up its rights to a compressor design it owned so as to convert that design into the engine we gleefully punish today. NSU moved the stationary seals to the apex of the rotor as in Wankel's design. In fact NSU also tried to sell it as a compressor, but nobody bit on the idea.

 

 Wankel was a sliding seal designer during WWII and his contribution was a collection and indexing of the many rotary engine and compressor designs up to that time. His design was one that had the crank case rotating at 2/3 crank speed, and other impossible features such as the spark plugs inside the rotor. How handy would that be? 

 

Its only redeeming feature was that it performed (in theory) with pure rotary motion. It was not useful for anything and was never produced in any numbers at all. The NSU Prince was the first rotary powered car. The engine looking remarkably like the modern rotary. The design (originally a compressor) had already been discarded by Wankel.  So, a Moped

(motorized bicycle) manufacturer NSU, brought you the rotary engine. Wankel thought NSU had ruined his idea.  

 

 

Lynn E. Hanover