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Originally posted by JasonESi_T
My software is the older one I believe. I'm not sure you could use the older software on the more recent ecu's. Apparently, the flashes for those ecu's may not accept them. Now whether or not the older ecu flashes accept the newer software is also up for debate.
According to Javad, the older ECU's need the old software, and new ecu flashes need the new software, neither are interchangeable..so he says 
I got that MSD knock alert installed, and it works really well. It's really sensitive and takes some adjustment of it's sensitivity controlls, but it def picks up the knock. The unit came with an adapter that fits right into several threaded holes on the back of the block. I chose the a hole that was directly above the crank angle sensor, right below the intake support bracket. Since the monitor unit was a nasty cream color, i painted it flat black, and mounted it right on top of the steering coloum cover in front the dash gagues.
I did more tuning, and was able to get rid of the really nasty knock, but i still get a little on a 5-4 downshift at 15 psi. And I think i've figured out why: stock ignition timing, and rapid rise in cylinder pressure..
If you think about it, chrysler tuned the ignition timing for 87 octane, and 9.6:1 compression N/A. We up our fuel octane to 93, and drop not even a full point of compression. On stock comression, and 93, we can put around 8-10 psi boost without getting any serious detonation, as long as the A/F is rich. Now, for every point in compression we drop, we can run approx 3 more psi boost, which brings us to around 13 psi or so for the stock ignition timing advance. So really, running 15 psi on 93 octane, is just a bit too much for the timing advance..BUT ONLY at PEAK TORQUE. Detonation is most likely to occur at peak torque, which on a stock cam 420A with the S16G, is roughly between 3900-4500 rpm, which is EXACTLY when teh knock occurs. This is made even worse, since on a downshift, we are building 15 psi VERY quickly, which raises cylinder pressure extremely fast, and since this is happening right at peak torque, we get the knock.
What we really need is the ability to have full control of our timing, on a pressure vs rpm grid. I know the MSD DIS2 programmable can do this, but it only provides retard on a pressure vs degree basis, not pressure vs rpm. We don't want to retard by rpm only, as lower boost will suffer power. The only real way to combat this is to run a full standalone.
What makes this even more complicated, is that as rpm increases, we can actually take advantage of the stock timing, which is around 20 degrees. Faster the motor is turning, the less time detonation can happen. Even at a really rich A/F, my EGT's are pretty hot. I would bet we could add a few degrees of timing past 5000 rpm, and that would bring down EGT's a bit, and also, maybe even lean out the A/F just a tad.
I believe what i've come up with is the issue, because i can be in 5th gear at 80 mph, and floor the gas, but boost builds slower up to 15 psi, and it doesnt knock. This is because we are at a slightly higher rpm, and we are leaving the area of peak torque, and also, the pressure rise in the cylinders is not so fast as on a downshift.
It makes me wonder if we can trip the ecu into open loop right at 0 psi. I notice that my timing will be right at 17 degrees with part throttle boost, but when going directly to WOT it starts at 17, but quickly drops to 12-13, then goes on up. If we could get the timing to drop like half a second earilier, by the time we hit 15 psi at max torque, the timing may be at 12-13 degrees, instead of 15-17. The 420A was designed, the head specifically, to be a fast burn engine. This motor just doesnt need a whole lot of ignition advance, because of the 4 valve, pentroof combustion chamber,and centrally located spark plug. There comes a limit how much boost pressure we can run, using the stock timing map..seems like 15 psi is that limit...for 93 PUMP GAS anyway.
Damn, this was long 
13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)
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: not sure, i think i may be stretching here, heh
