Thanks Richie,
Its a blast under boost indeed
and I am getting more and more used to it
I just reread the ignition map and it was 2 - 3 full degrees behind with what I think it probably 'needs'. It was now at 24-26 without correction, which was a setting which seemed optimal for twin-spark at the 98mm bore with the bit more CR and flat pistons. Probably not so much with this engine with pretty low dynamic compression...so I reset at 27-28 degrees for now.
I also dialed down the boost corrections a bit.
My target AFR under boost is 11,5.
Good point Eddie: I do have a knock sensor system, but for twin-spark it was not designed... so I contacted John from Safe Guard who made the system and he gave me some pointers how to modify the system. I didn;t understand it, but fortunaltely Robin did and he soldered the needed new connections in. At first I couldn't get it to do anything... Even on max sensitivity it didn't flash (did before at idle), so I thought it didn;t work and disconnected the unit. The above dyno was therefore without any safeguard.
Due to my extremely safe settings, it also never triggered I suppose.
Only just an hour ago when I tested again with the much less safe settings, it triggered at low RPM (3500) when boost came in early in fouth, so it finally works! Yeah! That also gives me the trust I can tune it more to the limit.
Back home I noticed some fields down low needed 13% more fuel...
so there's probably the extra power I was missing, but its a little early to tell yet as I have not run the whole map at WOT yet.
Clone (forgot your real name,,): The power curve is flywheel corrected. Its a 'heartbreaker' dyno though, compared to some (most) others I have been on
Not sure Carsten, that might need a little more time to check (boost leak). Seems tight, but I agree, could be the culprit for the curve. On the road it doesn't seem slow spooling at all though. At wastegate I was missing already 25% or so behind the 1:1 boost-power increase ratio, so I also knew something was off. Sure now it was at least timing, but could be another thing as well. With boost increase, the gain was very lineair, so it responded well and as expected to boost increases. Up to 1,6 bar, the boost stayed very stable at high RPM. Only the shown 1,8 bar decreased to 1,7 at max RPM.