Originally Posted by imaboa
Here's what I would do, if I had an hour (which in all reality will probably be about 40mins since we have to tie the car down, etc. etc.)
If your car still has closed loop fuel control, I would just focus on the WOT tuning, since you have probably spent some time with the partial throttle tuning on the street.
- Make a few pulls to establish a baseline.
- Watch the AFR curve to see if its where you want it, get that dialed in
- Set the Cam switch over point to a low RPM make a pull
- Set the Cam switch over point to a high RPM make a pull
- Set the Cam switch over point to RPM where the TQ lines of the two previous graphs cross
With those items complete, then I would mess with Ignition timing.
- Add 2 deg at a time to see what makes power, and where (RPM)
- I would venture to guess that a NA SR20 with good fuel is not knock limited, meaning that the motor will stop making power before it begins to knock.
Don't be anxious, or nervous, I'll be in the car to help you out and answer questions if you have them. My thing is, don't be afraid to ask if you're concerned about something. There are no stupid questions.
-John
Here's what I would do, if I had an hour (which in all reality will probably be about 40mins since we have to tie the car down, etc. etc.)
If your car still has closed loop fuel control, I would just focus on the WOT tuning, since you have probably spent some time with the partial throttle tuning on the street.
- Make a few pulls to establish a baseline.
- Watch the AFR curve to see if its where you want it, get that dialed in
- Set the Cam switch over point to a low RPM make a pull
- Set the Cam switch over point to a high RPM make a pull
- Set the Cam switch over point to RPM where the TQ lines of the two previous graphs cross
With those items complete, then I would mess with Ignition timing.
- Add 2 deg at a time to see what makes power, and where (RPM)
- I would venture to guess that a NA SR20 with good fuel is not knock limited, meaning that the motor will stop making power before it begins to knock.
Don't be anxious, or nervous, I'll be in the car to help you out and answer questions if you have them. My thing is, don't be afraid to ask if you're concerned about something. There are no stupid questions.
-John
^Very good advice.
The only thing a would add is the VE is knock limited below 3,000 rpm. It will knock like crazy below 3K rpm at wot, if the timing is not right.