I spent ages trying to optimise the EAE algorithm values. This is a clever "wall wetting" algorithm. But I just couldn't get it to work properly, so I gave up and tuned using the normal MAPdot and TPdot parameters. It isn't perfect, but it seems to work.
I also installed a boost controller, and added a second spring to the present wastegate spring.
Here is a screenshot from tonights datalog. The acceleration enrichment isn't perfect but the car drives well enough, and it is nicely controlled under full throttle so it is safe. Presently I am running a cautious AFR of around 11.5, but all in all the tune is pretty decent and gradually improving.
Boost duty controls how much the pressure comes from the turbo pressure and how much comes from the atmosphere. Confusingly 100% means use the outlet turbo pressure. 0% will allow loads of the control pressure to leach out. This would allow the wastegate to stay closed longer and so build up more boost.
If you look at the log, for low RPM I try to keep the wastegate closed for as long as possible to get the turbo spinning up quickly. After about 7kRPM the boost controller goes to 100% so that the boost is controlled purely by the spring. The thing is that there are forces from the exhaust gases that push the wastegate open and so the boost drops off with RPM.
I should be able to maintain the boost after 7kRPM by playing with the Boost Duty Table.
Now the problems:
1) oil leak, but I know where it is and it should be easy to fix
2) water leak into oil. This is the big one, but I have a plan.
3) starting, is still a nightmare. I think this is related to low battery and sub-optimal values, but it is annoying.
