[F-127]

Originally Posted by Power Hungry

The major concern with tuning for many of the windowed blocks that I've analyzed, was not pulse width... it was excessive timing and ICP at moderate RPMs

That's good to hear. I have basically left timing and ICP quite like a massaged stock, as well as most other maps.

By me trying to match the 238/100 flow output to stock injectors(AA), I figured it would work with the other stock single shot tables quite well. The main reason I thought I should be worried about PW was about the only map that was no longer stock. The only correction to make it fit with the other tables seemed to be trying to make a correction for injection duration.

I pulled some timing when injection duration is .5ms(or 9 degrees@3000RPMs) quicker and injecting the same amount of fuel because I thought that peak cylinder pressure is bound to happen quicker. Pulling the majority of that time had me feeling I was err-ing on the cautious side.

Now when I add .5 PW back where it is now short to start adding some power I imagine I could add a majority of the timing back, but possibly not all in effort to balance cylinder pressure, since there will now be more fuel injected during that duration.

Originally Posted by Power Hungry

Take, for example, you are running 2200 RPM with 1800 PSI ICP and that you have an SOI event that occurs at 30º BTC and the resulting SOC event occurs at 4º BTC. Raising the ICP to 2600 PSI could change the SOC to about 12º BTC, which in itself may not be a bad thing but when you consider that you are also increasing the fuel volume nearly 40%, you end up with a significantly higher Cylinder Pressure by the time you reach TDC.

Intersting, I was thinking that a commanding a higher ICP, resulting in a shortened PW was attempting to inject the same amount of fuel(I guess it also might depend on how the PW map is set up). I also had the thought that the majority of the 'advance' nature of the ICP was because of a reduced PW.

Originally Posted by Power Hungry

I'm sure that this may seem like a bit of an oversimplification, but once you got your head around the full relationship of SOI and ICP, it really starts to make sense.

I think my head is starting to grasp that relationship a little better now, especially after a well written post as you have made.

Originally Posted by Power Hungry

I hope this helps.

Absolutely! It's always great to read one of your posts and get some insight.