I've owned several turbocharged cars and it is recomended that you let the turbocharger "cool" before turning off the car by letting the engine run for a couple of minute (depending on how hard you drove the car in the past few minutes). Is there any procedure for turning off a car with a supercharger?

 

No special voo-doo needed, just turn the key to the designated "off" position and be on your way. Superchargers are the closest it gets to naturally aspirated in terms of drivability while still getting boost.

Gotta question tho - why would you ever want to stop motoring?

Cheers,
Ryan

 

The SC doesn't get nearly as hot as a turbo (no exhaust gasses running through it) and doesn't have an externally plumbed oil source to cool it down, so running the car after hard use is not necessary (any more than a naturally aspirated engine.)

 

eric- is that true even if you use like a 15% or 19% reduction pulley?

 

Yes, even with the pulley and ECU you don't need to do anything special on shutdown.

 

thanks DiD. im really liking superchargers over turbo's for commuting.
well, not just limited to commuting...


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03MCS IB/Blk: 123, Aerokit, R90 17x7, Anthrasite Int, TK5 16x7, 6CDMP3, etc.

 

The reason being that Turbos reach speeds of 130,000 rpms where a SC only reaches 15,000 to 18,000 rpms. Alot less heat generated internally.

 

It is still a good idea with any car, be it naturally aspirated, supercharged/turbocharged to drive easily a few miles before shutting it off after driving hard. However, our cars won't have severe premature wear the way a turbocharged car will if you do shut it down soon after boosting it hard.

 

>>The reason being that Turbos reach speeds of 130,000 rpms where a SC only reaches 15,000 to 18,000 rpms. Alot less heat generated internally.

I think that 130,00 rpms is a bit much. I was under the impression that turbos never spun higher than 30,000 rpms.


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2004 MCS Indi Blue /W Sport, Lapis blue interior - Stock for now, but not for long.

 

The main reason this is necessary for Turbo's is they get extremely hot...due to the exhaust gases that make them turn. In fact, the whole housing will start to glow red hot during a good hard drive. Since you've got oil being pumped through the turbo bearing while the engine is running, there is no problem wityh this high heat. But, if you come off the freeway and immedatly shut down a turbo engine, the bearings starve for fresh oil and the now stagnant oil sitting on the very hot bearings/housing starts to "coke" as it burns away. This leaves an ugly hard rough residue on the bearings...which can lead to a future failure.

SC's do not run at these temps and there is no fresh oil supply running to them (usually). No benefit from a cool-down idle period.

Mike.

 

Ok..It's definatley not 130,000 RPM man...no way,nothing would hold together at that rate.

 

Thats why some people with turbos get a turbo timer