.  I ran the Sun 100 race at very lean

condition, only 1 bar flashing on the mixture monitor.

Tracy

I'm curious - why?  When in a race, wouldn't you want to run near max
power?

Al

Haven't you heard of sand bagging Al?   : )   Gotta save something for next
year's race in case those Lyc drivers come back with more power.
At best power mixture my engine will burn 20 GPH.  I leaned it to 16 GPH
initially (off bottom of mixture monitor scale) but gradually richened it to
17 GPH as my "race tape" started peeling off and created drag.

On the subject of my engine configuration,  the side housings are 2nd gen 4
port turbos with only a slight port cleanup.   Ports were raised about .1"
(closing later) which is less than a mild street port engine.  I found it
very interesting that the RX8 engine does not open the secondary port barrel
valves until the engine reaches 6250 rpm.   Radical port timing may not be
the right thing to do at 6250 or less.

Tracy

Port timing is one thing intake area another. The Rx8 has 30% more intake
area and it has 167 HP at 5500 RPM, 185 HP at 6000 RPM and  198 HP at 6500 RPM.
Porting an engine does not necessarily mean changing the timing. There are a lot
of compromises in the intake system to improve the torque in the 3000 to 
6000 RPM range. A rotary car engine's biggest problem.

The RX8 HP curve is pretty much a straight line between 13 HP at 1000 RPM to
250 HP at 8500 RPM. 

I am absolutely certain Mazda compromised the port timing on the RX8
motor to get more torque in the 3000 to 6000 RPM range.

In fact the RX8 motor has identical intake timing to the 3rd gen turbo engine.
Only the exhaust port timing has been narrowed because they could
and still double the port area.

What is the port timing on your engine?

Paul Lamar
 
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