Ignition Timing Out After Swapping Rb20's

[iz32]

ok this is just for curiosity sake as EMS is going in very soon but how is it possible for the ignition timing to be out after swapping RB20's over???

the reason i believe the timing is out is that it pings above 1.1bar and on the dyno its afr is just above 10 when the ping starts so there is plenty of fuel.

but by experimenting just for the hell of it i turned the CAS clockwise about 4mm and it will now take 1.3bar but producing less power...understandably

now the remapped ECU is the same and the timing was spot on on both RB20's (until i messed with the CAS on the new one)

i thought the ecu controls the timing or is there some other funky business going on that i dont know about..........??

is there any other sensors or factory adjustments or connectors involved in controlling the ignition timing that could be out of sync?

if a cam gear was one tooth out would it give me much more grief then ping at high boost? im assuming major idle problems.

just doesnt make sense..

previous engine ran very nice above 1.3bar with a bucket load more power.

[blind_elk]

The ECU can only control the timing if it knows where the pistons are in the combustion cycle. Guess what the CAS does?

[iz32]

The ECU can only control the timing if it knows where the pistons are in the combustion cycle. Guess what the CAS does?

yes but if the cas is in the correct position as per manufacturers spec on both engines then why would there be pinging on the newly installed engine at lower boost levels with a rich tune (a/f ratio's proven on dyno)

am thinking an issue in the inlet manifold area.... ?!?

everything on the inlet side bar the inlet manifold and throttle body was swapped over from the previous motor.

got me stumped.

any ideas?