Approaches for cooling the motor?

[hcsharp]

The last parts are arriving Saturday for a not-in-car CO2 cooling test.

20lb CO2 tank (aluminum tank at 24lbs plus 20lbs of CO2), inverted to draw off liquid CO2 from the bottom (the tanks with a siphon tube are steel and much heavier), running tank pressure down the lines (3000psi rated), feeding two nozzles which go from ~800psi liquid CO2 to spraying mostly fine dry ice.

I look forward to your results! Didn't Tesla try a nitrogen cooling system in the Roadster as an experiment a few years ago when Joost was still there?

 

[wycolo]

For competition shouldn't you jumper the fan ON before start of race rather than waiting for delayed response?
--

 

[nick]

Static test of CO2 cooling parts...

Tank was full so liquid draw when horizontal. Plan is to mount the tank upside down.

Flow rate is 2.5-2.6lbs/minute so 85% usable off a 20lb tank is about 6m30s of run time.

 

[nick]

Installed and track tested...

 

[hcsharp]

Installed and track tested...

Well??? How much longer full-power run time did you get?

 

[eye.surgeon]

Buy a track car? How much fun is it really to track a 5000 pound family sedan.

 

[FlyingCookie]

Buy a track car? How much fun is it really to track a 5000 pound family sedan.

This is not the subforum you're looking for...

 

[nick]

Buy a track car? How much fun is it really to track a 5000 pound family sedan.

I have never tracked a 5000 pound family sedan so I can't answer that from first hand knowledge, though I am pretty sure I could have fun on the track in anything with 4 wheels and running slicks.

 

[nick]

Well??? How much longer full-power run time did you get?

The first session I did the warmup lap without cooling, then 4 laps before the CO2 ran out.

The next two sessions the motor quickly overheated with gas left over - discovered the nozzle was blocked from small chunks of the teflon tape used on the threads.

The last three sessions the CO2 cooling worked - the battery overheated before the motor. The car has air-con cooling for the battery pack but it only seems to use it for a short time to get the temp just below the overheat threshold.

If I could force the air-con battery cooling to run for the full 40 minutes between sessions the battery might cool down enough to do the 4 laps the CO2 can support.

Could easily run two tanks of CO2 together to double the CO2 run time... then we would know how many laps the battery can do when cold and determine if it is worth it.

 

[ML Auto]

This might help you.

Manual battery cooldown mod - a cure for the Roadsters insomnia

 

[djp]

If I could force the air-con battery cooling to run for the full 40 minutes between sessions the battery might cool down enough to do the 4 laps the CO2 can support.

The battery cooling is more aggressive if you charge in Range mode. It won't run continuously, but it does target a lower temperature than a standard charge.

 

[TTimeAttack]

Any updates on this thread? I will be competing in Time Attack in my ‘17 P100D Model S and in car testing, yes, motor cooling is an issue.

Thanks
-Churchill

 

[nick]

Yesterday was the 2018 ReFuel track day at Laguna Seca... I recorded an official TT time of 2:00 (.264) which is a personal best and put me in 9th place for the day.

This was the first track day where the battery didn't overheat, thanks to this mod:
Manual battery cooldown mod - a cure for the Roadsters insomnia

I turned the air conditioning on while waiting pre-grid (~10 mins), left it running for the 15 minute session, came back in with the battery one below the orange, then gave it 5 minutes to cool down to 2 below the orange.

Motor still overheats after ~2 laps... really need to come up with a solution for that.