tuj

Does anyone have a good reference for various rotary-engine geometries / eccentricities? I'm wondering what the relations are between rotor width, e-shaft offset (stroke if you will) and housing diameter. Mazda seems to have settled on the current 13b-type geometry back in the 70's, so I'm wondering why they've been so reluctant to try other configurations? Granted, the volume of rotaries is relatively low.

One major problem I've heard about the rotary is flame propagation across the wide and long combustion chamber. Why not make the rotor face wider and use 2 spark plugs? The rotor face could even be shaped to nearly meet the housing in the center, and dished on the edges for combustion. This would seem to be better in-line with the all-side port engine format that Mazda will likely use on all future rotaries.

Information on rotary engine design is woefully scarse online. Any good books / links?

zoom44

rotaryengineillustrated is a good source and im pretty sure the howstuffworks article talks about the relationship between eccentricity etc. there is a math forumla for figuring it out.

also we already use 2 spark plugs

Cattywampus

Find Rotary God on here. He will let you know whatever you want. he's the rotary genius

tuj

I guess I should have been clearer. I mean using two spark plugs side-by-side, perhaps in addition to the trailing plugs (which would bring the total to 4). Wouldn't this aid in making sure all fuel was fully combusted?

shelleys_man_06

PM me. I have tons of info.

zoom44

hahahah check out the forum on rotaryengineillustrated!! they were talking about that exact thing with pics of a Rob Golden engien with amny spark plugs but basically no it doesnt help much at all

rotarygod

Mazda actually tried that when they were developing the current Renesis engine. They tried 4 plugs per chamber, 2 leading and 2 trailing side by side. It did more harm than good. There are now multiple flame fronts colliding and this increases the chances for detonation. The current system works the best. You can actually do alot for combustion by changing the timing split between leading and trailing but simply adding plugs isn't a usable idea.

Cattywampus

Told ya he new everything about the rotary. That is all foreign to me. Hey by the way, thank you rotarygod for the info we talked about a few weeks ago. It helped

rotarygod

Did your friend get his car retuned (tuned!)?

zoom44

here is the pic of Robs engine

Cattywampus

Yes I did. I told what you said. He said he knew a little bit of it but not all. He said bottom line is that now he knows the g35 is not good to modify unless you are willing to redue the whole engine. but still a good car and very quick. Just not made for force induction with that alone.