Ignition timing vs spooling turbo

How does ignition timing affect how a turbo spools up?

I road tuned backed off 3 degree timing from -4 vac to 8psi turbo seems to spool up much quicker

Tuning gear: Knock box

Aem Wideband

Vehicle: Toyota Mr2

Setup: Borg warner s366 turbo

HKS 264 cams

Wiseco 9:1 pistons

Haltech ps1000

max boost 24psi

Hp: unknown

The answer is that yes igniton timing can effect the way the turbo spools. What we are trying to achieve to spool the turbo is maximise exhaust mass flow as well as exhaust gas temperature. While retarding the timing a little can increase the exhaust gas temperature, we will also find that as we move away from MBT timing, the engine naturally will start to lose torque.

My personal experience is that the best way to optimise turbo spool up is to optimise the ignition timing to MBT at each point in the rpm/load range during the spool period. You can find that using a slightly leaner AFR during this same spool period can have a slight positive effect on boost response due to the increased EGT.