JekyllandHyde

iTrader: (3)

I had a question about the timing strategies between auto and stick cars. Comparing AUJP (350/Auto), AXXD (305 5-speed), and AXCN (350, 6-speed), I can understand some of the differences, but one thing I don't understand is why the timing is so low in the stick bins for the low rpm high load areas. For example, in AUJP, in the 80-100Kpa and 400-600 rpm area, the timing is 20.04. In the AXXD and AXCN bins, the timing in those areas is 6 degrees and 10 degrees respectively. Why is that? I would think that the added timing in that area would help the motor stay alive if the clutch is let out without enough gas, no?

RBob

iTrader: (1)

Lots of reasons. For auto's need to run the engine up against a heavy convertor before the vehicle starts to move.

Stick car, direct connection, also needs to be driveable. A lot of SA makes for a jumpy/jerky ride.

Emissions.

RBob.

JekyllandHyde

iTrader: (3)

Thanks RBob. After studying some datalogs and trying to diagnose why my car stumbled and tried to stall in an intersection with oncoming traffic at low rpm high load conditions, I bumped up timing in those areas and noticed a big improvement in driveability. Now I just need to figure out why sometimes it almost wants to stall when I push the clutch in too quickly.