Cool. after a play with neg split myself i can see no reason not to run it in very low vac. The rx8 has got me thinking that mazda have looked into this. The only reason i can think of is for gas mileage etc but it must have a nock on to all rotaries

Scott

gas milage is one thing, but it knocks a noticable amount off the egt's too. this is especially useful for the renesis motor and it's 10:1 compression... egt's are crazy-hot on those motors.

the other reason would be emissions....

Okay, this thread has me going to do for a PCM that controls ignition, so that I can play around with such weird, wild timing curves/maps.

Damn you for making me spend more money!!!! :)

i know! ive got the weber for mine, but efi is the way to go

When I installed my first E6K I was under the gun by the Air Force to relocate to another base. Hastily and due to a lack of sleep I wired the Trailing and Leading backwards. SO i was runing Trailing first. and had about a 5*- 10* split. I drove that car from Abilene TX to Columbus AFB MS, then to Daytona Beach. back and forth for the Holidays..about 6K miles. It pulled strong and was really responsive in Vac. Eventually it overheated in traffic (thanks to my roomate) and the motor let go. When I took the motor apart, the front rotor was SEVERELY dented above every single tub. Really bad detonation. Moral of the story, it held for as long as it did. and in Vac neg split is really good for throttle response. I'm too chicken shit to try it again. Plus my E6K can't control that.

the rx8's make a "chirping" noise around 2000-2500, at really light throttle that mazda says is pinging/detonation, there is a bulletin

you're gonna have to show me that one. it's incredibly hard to make an engine detonate at really light throttle (i'm assuming 20" and above), or at such a low rpm.

CHIRP NOISE ON ACCEL OR ENGINE START
Applicable Models
2004 - RX8 VIN Range: 000000 - ZZZZZZ;
Symptoms
110 PINGING
820 UNUSUAL NOISE(EXCL. PINGING,SQUEAKING,OPERATION,RESONANCE)
MTOL - 4181 Dealer Repair Information
A chirp or squeak may be heard at times from the engine compartment.
This can occur at engine start, or during engine acceleration. The
noise can easily be mistaken for a squeaky accessory drive belt. The
noise is actually caused by a slight momentary lean mixture, which
results in engine detonation.(Pinging) The RENESIS rotary engine runs
much leaner than previous rotary engines, resulting in improved fuel
economy N lower exhaust emissions. This momentary lean condition will
not cause engine damage.

IMPORTANT!
It is important to note that customers who use low octane fuel will
experience a noticeable increase in engine noise. The RX8 requires
premium fuel for best performance N engine life.

FUEL: Octane rating (Anti-knock index):
Premium unleaded fuel 91 (R+M)/2 method or above (96 RON or above)

Fuel with a rating lower than 87 octane (91 RON) could cause the
emission control system to lose effectiveness. It could also cause
engine knocking and serious engine damage.

I got my street ported 12A to detonate at anything over about 1/3 throttle, at 2500-3000rpm. Basically the amount of power needed to cruise at 60mph. Not even into the secondaries yet.

The problem: When I put the engine in the car, I installed the distributor 90 degrees out.

How this happened: With the stock engine, I'd installed a MSD with two leading Blaster coils and set timing to 24L/16T. When I pulled the engine out, I just removed the distributor, bungied it to the fender, changed engines, and then stabbed in the distributor. I paid no attention to the rotor position, just lined up the reluctor to the pickup. When I had the engine running I set the timing, but I only checked the leading side, figuring the trailing could not change in relation to leading. I was half right :)

The leading checked out okay because it was waste-spark. The trailing was 180 degrees out, so instead of 24L/16T, I had 24L/196T.

Being lazy, after I found the problem, I just switched the plug wires around. Pulling the distributor on an SA means pulling the A/C compressor bracket, which is far more difficult than it really needs to be.

When it happened, it was a funky chirpy sound. I thought it was an alternator bearing starting to sieze at first. But alternator bearings don't cause black smoke and the whole car to jerk and lose power :) I made it happen many times while I was trying to figure what the hell was going on, at least 50, maybe 100 pings. Totally did not sound like "normal" pinging.

i hereby officially stand corrected.

my bad, ladies and gentlemen :p: