Paul, everyone.


In the interest of redundancy and safety I have been doing drawings on the
possibility of installing two leading plugs.  Each would be fired by
independent ignition systems.  One a mag, the other a C.D. system.

The leading plugs are the critical ones. Therefore I've look at two plugs
angled in towards the middle which would result in two angled intersecting
holes at the housing middle.   Another way to do it would be to plug the
center hole and drill two new holes side by side.

The first way would bring the fire into the middle but would create a
chamber of about 1 cc cubed.

The second case is obviously easier and like Paul suggested in an earlier
post there is enough metal (almost 10mm in the inner housing to tap and
thread a aluminum insert into it. The outer housing has enough thickness so
it could be stepped for an 0-ring seal or epoxied in.

On the straight through approach the pitch of the holes would be 30mm on
center or in other words 15mm offset. I am concerned if one ignition system
goes down would the remaining firing plug cause rotor imbalance because the
center of combustion is offset?  Lycs and Continentals obviously can run on
one ignition system and the distance between plugs is two to three times
greater.

Any comments would be appreciated as I can't find any material to suggest
Mazda or anyone has ever tried this.

Doug Fir

I can see how this would add to the electrical reliability
of the ignition system. Unfortunately this is the most critical
area of the Wankel rotor housing as far as cooling is concerned.
Mazda is still doing research and changing this area as far as
the exact configuration of the water jacket is concerned.

The early one rotor NSU Wankel Spyder got it wrong and
the rotor housing would crack straight through the spark
plug hole.

When the rotor housing melts after you run it at high power
without coolant for awhile this is where it starts melting.

Therefore it is highly risky to modify this area.
On the other hand it might help if a little R&D was done by
installing some thermocouples.

BTW This is another reason you don't want to nickel and
dime the cooling system plumbing by using automotive hose
and hose clamps. Use only silicone rubber hose and constant
torque hose clamps or better yet -20 or -24 AN lines.

Baker Precision down the street from Mazdatrix now has
forty five degree and ninety degree bends in the one inch
size silicone hose. They don't have constant torque hose
clamps yet but you can buy those in every truck stop
in the country. When I need AN fittings and hose Baker is
where I go.

http://www.bakerprecision.com/splsilicone.htm

I know you know all this Doug but it is worth repeating
for the new subscribers from time to time.

Paul Lamar ...No rotor no motor.

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