all thanks guys, i will order my lipos + lvc tonight...

Well that is some cool cooling for motor.
I find if you buy a better motor like lmt or neu. It runs cooler than the cheaper ones.
7xl on 4s with 16 51 gearing sound good with hb buggy diffs.
The neu 1512 2.5d has about same kv as 7xl. I am going to test this out.
It is a 4 pole motor so doesn't work will with 9920.
As for lvc I run the single unit that detects the amount of cells on it. It works great so far.

And you will have more success blowing air across rather than sucking air past - i have tried this more than once - BTW - i like the cover over the speed controller..

Ok for blowing on the motor, i believe in you HotnCold...

For the lipo thing:
I will have to make a Y harness to connect the two 2S tabs together ... after that i will plug the 4S tab of the Y harnes to the LVC... do i understand correctly? (i would buy the cellpro LVC...)

Are you talking about the Graupner?

i thought about the FMAdirect Cellpro 4S DPM low voltage cutoff... is there sthg better on the market, but that doesn't cost mnore than 40 to 50$ ???

I would go for the Li-Saver.

The Cellpro watches the voltage of each cell. That's far better than the LiSaver, which can't watch each cell. It helps to keep all of the cells healthy.