nsogiba

I realize that this may not be everyone's style, so flame suit on. If you don't have anything positive to contribute, don't bother. Thanks in advance.

I'm a novice tuner trying to achieve two separate "effects" with my 2000 C5 6 speed.

First is a "shotgun blast" effect during a No Lift Shift.

It already has the N2MB WOT BOX installed and no cats, but only gets a big backfire once in every 20 No Lift Shifts (which cuts spark). I want to make this something I can do "on demand". Above a certain RPM (say, 4000, would be fine). Is there a way to retard timing as the clutch is pushed in during a shift? If not, is there some sort of condition in which the g/cyl or cylinder airmass changes during a no-lift shift that I can take advantage of to fool the PCM into retarding timing?

The second is a crackle on deceleration, which I seem to have figured out by retarding timing in low engine load scenarios is all the spark tables and shutting off DFCO.

Here is a log from some No Lift Shift events (full throttle, press clutch to floor, quickly perform shift, release clutch. Never let off the gas). You can follow it by watching the TPS stay close to 99.6%, and speed will actually spike (wheelspin) followed by a drop in revs as I let the clutch out.





Unfortunately there aren't any big airmass changes, which at this point is the only control I have over changing timing during an event like this. But, there must be some other parameter I don't know about that's rapidly changing during a NLS (look at the O2 sensors switching as the mixture goes full rich when the spark gets temporarily shut off). I'd love to take advantage of that and use it as a control to retard timing...

The last ditch effort is adding fuel above 5000rpm or so (which is where NLS occurs) but this will probably kill some power and have negative effects elsewhere so I'd rather not pursue that. Then again, it may not be that bad. Not even sure how to alter the fuel mixture.

Thanks in advance!

nsogiba

whoops, double post.