Timing Question

[nicr4wks]

Consult is reporting my timing as 5° BTDC at ~800rpm on warm idle, FSM states idle should be 15° BTDC at 650rpm.

Would this affect timing over the whole rev range, and overall power? If I fix the idle so it's at 650rpm and the timing is still not correct, do I just adjust the CAS until it is back in specification?

My 33 is pretty low on power, 150rwkw on 12psi so slowly going over everything.

[NewKleer]

if car is idling higher than target rpm then the lower reported timing is likely the ECU trying to lower the timing to reduce rpm.

try turning idle screw down, and maybe once the ECU is 'happy', timing goes back up to normal.

the ecu's reported timing is assuming the timing is correctly set with a timing light, it has no way to know actual timing, so changing the cas will not change what the ECU is reporting, cause its an 'output' value only.

[nicr4wks]

Thanks NewKleer

I got hold of a timing light, and confirmed the idle timing was at 5. I turned the cas and managed to get this up to around 10-12 as the timing seemed to be jumping around a lot, the ecu then reported 5-7 at idle and the car drove much smoother and puled harder.

As the cas is now turned as far as it will go and I'm still not at 15, I'm thinking of trying another one to see if my cas is faulty.

[mad082]

pretty sure that adjusting the CAS will not show a timing change in the ecu as the ecu purely uses the CAS as a reference point. when the timing is set at 15 degrees and the ecu says 15 degrees then it will be 15 degrees. if you retard the timing via the CAS to 10 degrees with a timing light, the ecu will still say 15 degrees however it will actually be 10 degrees, but ecu won' know it.

have you been using the consult program to put the car into base idle/timing mode before adjusting the timing? if not then the ecu may be altering the timing and you may actually have it set at 20 degrees or higher. you need to make sure the car is in base ilde mode (best to have the car to be up to operating temp) and then adjust the idle to the desired rpm and then check the timing.

[JonnoHR31]

Thanks NewKleer

I got hold of a timing light, and confirmed the idle timing was at 5. I turned the cas and managed to get this up to around 10-12 as the timing seemed to be jumping around a lot, the ecu then reported 5-7 at idle and the car drove much smoother and puled harder.

As the cas is now turned as far as it will go and I'm still not at 15, I'm thinking of trying another one to see if my cas is faulty.

your doing it wrong and potentially dangerously.

set it back where it was, as that was correct and wind the idle screw down as newkleer said

[NewKleer]

yes you should only adjust the cas when in 'base idle/timing mode' via consult (or similar manual method) which would lock timing at its static value. that consult said 5 deg (should be 15?) means it wasnt in this mode.

the consult output for timing is the ecu's calculated value assuming timing is set correctly with a timing light - the ECU has no way of 'reading' the timing, otherwise it wouldnt allow you to adjust it via the cas...