So after having run the remote controlled exhaust flap for one week, I must say it is sooo nice to be able to enable and disable the DME signal. Since my Z4 runs two exhaust flaps, with the flaps closed, the car is actually more quiet than stock. My only worry now is whether I am actually hurting the engine when cruising with such a restrictive exhaust. Someone please tell me I worry too much. The way I run two flaps is by having the passengers side muffler installed on both sides.
Yesterday we finished installing the separate water methanol container with level switch for the injection system. I went with a 7L / 1.8 gallon container priced at USD 4. It is exactly the same type of container used by local chinese WMI brands sold at +70usd. Felt pretty good when I figured out which supplier they were using haha.
View attachment 36458
What this means is that I can now run permanent WMI. I no longer need to worry about using water from the warm wind screen washer fluid tank. Also I can add methanol as I don't need to worry about the contents ending up on the wind screen. The wind screen washer fluid tank will still serve as container for the external water spray.
View attachment 36456
We also managed to wire up the new oil pressure switch to a loud siren mounted inside the cabin. The switch replaces my previous oil pressure sensor, as I will no longer be running an oil pressure gauge.
View attachment 36457
The switch is adjustable between 1-5bar, and we set it so that the siren starts making noise when the pressure drops to around 50-60psi, which happens at idle when the oil reaches 75-80C. This means, when the siren is turned on, it will sound at idle, and turn off as you drive off. As you drive around the track, it wont sound unless oil pressure drops below that set point. I like this alot, as all experience shows I don't see any warnings on the dash when pushing on track. Some track cars are so loud that you can barely hear your own car when passing them.
The switch used to turn off the siren is linked to the external water spray as well as the semi-dry oil sump, so it acts as a reminder that those systems are still on when idling in pit, which gives it a nice dual purpose. Of course none of these systems are to be used on street either.
It took four hours just to figure out all the wiring, so hopefully we don't have to do that again haha.
Now Im just waiting for my dampers to finish production, and then there's the rod bearings and oil sump enlargement. Last topic is wider wheels, but that can wait.