
That 20 amp fuse worked just fine with the spal fan. But e39 fan required at least 30 amp fuse to work. So that tells about how much more powerful that one is compared to the spal one.
Also the plastic thermostat housing started to leak, so I replaced it with aluminium one:

And as I earlier said, I had problems with the vanos not working. Here is log about what happens. The vanos should follow the vvt duty:

But yeah. It doesn't come back to base position at all when the car is accelerating.
To fix that I took the vanos unit out of my e36 that had freshly replaced vanos seals (I didn't want to wait for new seals to arrive). And I also modified the vanos with m52tu vanos solenoid and solenoid spring and modified valve. To achieve PWM controlled vanos. Instead of the m52 on/off vanos.

I also drilled the oil passage larger because it's quite restrivtive in m52 on/off vanos compared to m52tu PWM contoller vanos. Probaply to make the vanos to move more slowly with the poor on/off control scheme. But that too slowly moving vanos has always been problem in fast revving tuned m52 engines. And I wanted to fix that with PWM control.

The system worked on bench so it was time to install it to the car. I changed the megasquirt vvt settings to PWM controlled and did some testing. First tests showed horrible oscillating vanos angle. Like in this log:

I then noticed that about 50% duty the cam angle stays same and below that is decreases. And above that it increases. So I enabled the hold duty at 50% and did another test.

Well now it follows target quite well. I then did some testing with different vanos angles and got results like this. My vanos solenoid had loosen bit, so it was oscillating again. Just a little bit. But I still got good results.

So basically you need to read that so that the leanest AFR is the best vanos angle, because it means that there is biggest amount air coming into engine with that vanos angle. After looking at the logs, I came up with this vanos map:
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¨Here is also how the vanos angles affect the turbo spool:

So really noticeable difference. I didn't include the log with fully tuned vanos. But boy it's like ten times better engine after I tuned the VE map to match new vanos maps. The turbo spools about 500RPM earlier than it did before. And now the throttle response is instant even at low RPM. Because the vanos turns all the way in less than 0,5 second. When previously it took over 2 seconds to do so. And because the vanos angle is spot on even really low RPM, it feels like I'm driving bigger displacement engine than before. The difference is huge. The PWM vanos mod has been the best thing that I have done for the engine in long time. It doesn't give me bigger torque/hp ratings in dyno. But the engine is totally different off boost below 3000 RPM. Where 95% of my daily driving happens.




 
					







































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