I was just wondering about a few things. I think this one was programmed by Robert but Elwesso may know for sure.
Is valet mode just the stock map with 3k rpm and 60 mph limits set in? I was reading the fsm and there is a failsafe mode that uses a 3k rpm limit and sequential injection when using the secondary CAS and was wondering if this was actually what the valet mode was doing.
Also, what is happening in stages II and III? How is the fuel and spark altered? Just curious, I am going to dyno the Z when it's done and broken in and don't want to look like a dumb *** when they ask me what's done to it. I'm sure they will be able to tell me what it's doing by the AF/spark numbers but I just wanted a heads up.
thanx
A few Q's about the NICO ecu programming
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Q45tech
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Re: A few Q's about the NICO ecu programming (T45)
The maximum peak BMEP [torque and horseypower] occurrs when the maximal pressure occurs around 16 degrees after top dead center. the point where downward pressure exerts the most translatable force on the rod and thus crankshaft.
Oem always use timing that is earlier than this.
The timing is a function of actual spark advance, the flame speed of the mixture [which changes with AF and air temperature.
The concern is the point where 66% of mixture has burned aligns with 16 ATDC
There are two variables controllable: Spark advance and A/F ratio [injector open time]. You can accomplish the same thing with each or find a combination of adjustments that complement each other AT SOME PARTICULAR AIR TEMP for a very specific individual gasoline combination.
What works with one gasoline on one day may have a different result with the same brand [but different days refinery] and at a different temperature.
Visualize a normal curve [gaussian curve] but weighted a little to left inthat richer or less advance has less effect than leaner or too much advance [until knock occurs].
Obviously the coolant temp and residual after exhaust cylinder wall temperatures modify the local ingested air/mixture temperature and thus flame speed.
Why one has a different advance curve if only a quarter mile is a concern vs a 1-5 minute road race............................even a dyno derived curve may have too much advance as the dyno allows faster than quarter mile acceleration.
What good is it to tweek in 2 more degrees of advance IF the KS system takes away 5 degrees.
Oem always use timing that is earlier than this.
The timing is a function of actual spark advance, the flame speed of the mixture [which changes with AF and air temperature.
The concern is the point where 66% of mixture has burned aligns with 16 ATDC
There are two variables controllable: Spark advance and A/F ratio [injector open time]. You can accomplish the same thing with each or find a combination of adjustments that complement each other AT SOME PARTICULAR AIR TEMP for a very specific individual gasoline combination.
What works with one gasoline on one day may have a different result with the same brand [but different days refinery] and at a different temperature.
Visualize a normal curve [gaussian curve] but weighted a little to left inthat richer or less advance has less effect than leaner or too much advance [until knock occurs].
Obviously the coolant temp and residual after exhaust cylinder wall temperatures modify the local ingested air/mixture temperature and thus flame speed.
Why one has a different advance curve if only a quarter mile is a concern vs a 1-5 minute road race............................even a dyno derived curve may have too much advance as the dyno allows faster than quarter mile acceleration.
What good is it to tweek in 2 more degrees of advance IF the KS system takes away 5 degrees.
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elwesso
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Re: A few Q's about the NICO ecu programming (Q45tech)
valet mode is 3k RPM and 60MPH. When you're programming the ECU theres simple values (constants) that you change, so the program is very simple. We dont trick the car into thinking the CAS or MAF is bad..
Stage II cuts back on fuel and increases timing.. Stage III is basically stage II with more timing. It also does some other things on the top end, but I cant recall what those are right now. I'm pretty sure it ignores the O2 sensors and the KS, which is why I dont offer stage III alone, because you can get some detonation with stage III and you need to have "fall back" with stage II, which is safe to run on 91 octane all the time.
Stage II cuts back on fuel and increases timing.. Stage III is basically stage II with more timing. It also does some other things on the top end, but I cant recall what those are right now. I'm pretty sure it ignores the O2 sensors and the KS, which is why I dont offer stage III alone, because you can get some detonation with stage III and you need to have "fall back" with stage II, which is safe to run on 91 octane all the time.