The problem with widening the current chambers is flame front travel. We already have the issue that some parts of the combustion chamber don't completely get burned since the flame front can't get there fast enough. By widening the rotors, you may get a power increase but it will not be an equal amount of gain compared to the amount of added displacement.

The 13B engines made alot more power than the 12A's but alot of it didn't necessarily have to do with displacement. The peripheral exhaust ports can only get so large. The 13B could get much larger exhaust ports than a 12A and therefore breathe better. 12A's have still gotten over 600 hp heavily turbocharged. A side exhaust such as the Renesis would take care of this. Now you can have the same size exhaust ports with smaller displacement. This is kind of like putting bigger ports on the same sized engine without changing the timing. You can really get some nice flow into the small chamber. The flame front also doesn't have as far to go. Personally I would like to see a 3 rotor version of the Renesis based on 12A dimensions. If we aren't talking about high boost levels then shaft flex isn't a problem. I think this would be a very nice nonturbo or positive displacement supercharged engine. 3 rotors just sound cool too!

For custom 3 rotor machining, contact Jeff Bruce in New Zealand. He builds 3 rotor parts (eccentric shafts, intermediate housings, etc...) from machined 2 rotor parts. He is very good. I need to go dig up his contact info.

Would just a simple change to 3 plugs per rotor or do a bit more timing change the flame travel ?

Mazda has experimented with 3 and 4 plugs per rotor, even on the side port pre-Renesis engines and found them to not work any better. The issue is really a distance problem. We also have a moving combustion chamber in relation to the plug locations. Timing still doesn't solve the distance issue.

The largest working rotary ever built was an experimental one that was about 7 feet tall or so. You've probably seen pictures of it. It was a 1 rotor and made 700 hp at an astonishing 100 rpm. The issue was that the combustion chamber was so large that the flame front could not travel across it effectively at any higher rpms. This was an extreme example but relevant never the less.

A product in development that I am very excited about could solve this issue. They are called smart plugs. They do not get fired by a distributer and are triggered through piezo electronics. They are not glow plugs though. Their flame front is huge since the patten is so intense. They send an explosion into the combustion chamber rather than a spark. Here's a link. Check this out. If I can get a hold of some somehow, I will. They are not available to the general public yet but have been used on rotaries. They can run anything from regular fuels to hydrogen to diesel fuels all on the same plugs!

http://www.smartplugs.com/about.htm

dcfc3s,

The silver Scoot car shown in the pics is the SAME as the red car you mentioned with the rear side skirts. This is what Scoot evolved the car into following his Japanese top speed efforts.

RG,
is my avatar the giant one you are talking about?

hydrogen you say? i wonder if Mazda is already experimenting with them in their hydrogen/hybrid rotary........

That's probably it. I hadn't seen that picture of it before.