[ZeRoSL]

So, now that REAL electric superchargers exist, and are no longer power draining 12v garbage, these 48v units seem like they would work for small displacement engines?

Had a crazy thought... put it in a lotus.

from what I have heard, it acts almost like NOS, but would require tuning.

Any thoughts?

 

[exigegus]

the efficiency lost with the comversion of mechanical power to electrical then back cannot be worth it

 

[steelypip]

the efficiency lost with the comversion of mechanical power to electrical then back cannot be worth it

Um, that's true of most shaft driven superchargers. Remember, the things were invented to enable airplanes to fly higher by maintaining sea level mass airflow at altitude, not to boost specific efficiency or gross power. It's true that if the VE on the engine is low, you can get some net gain from supercharging, but you've added weight, complexity, and heat management issues to your engine to do it. The math doesn't uniformly work out beneficial - if it did, everything would come with a shaft-driven supercharger. I suspect the major reason it's so popular on Lotus is that we have alloy engines and light platforms, so hurting the power/weight ratio of the powerplant for more gross output isn't all that horrible an idea if everything is sized just right.

The magic to an electric supercharger is that, like nitrous, it is extra power just when you ask for it. Unlike nitrous, as long as you put it behind the MAF, you should get some goodness from it up to the limits of the ECU, injectors, and MAF to understand what you're doing without having to have a supplemental fuel injector. Running an electric supercharger all the time is indeed dumb. Running one when you're at WOT and going up through the gears should work out quite well as long as you have enough amp-hours in the battery to keep it going for the 10 seconds you need it, and you limit the power draw of the alternator during the recharge cycle. BorgWarner sells one as a fix for turbo lag, which is also one of AerisTech's use cases.

Magic? no. Useful? Maybe. Depends on the use case.

 

[ZeRoSL]

I do think for many it could be useful. I feel like my NA power is sufficient for most cases like street use, but there are times when i could use that extra pep, especially on the straightaways during track use. I did think about nitrous for such uses, but realized the cost didnt make sense. I think an electric supercharger might JUST make it work... though I have yet to find out any information on charging times for the 48v pack

 

[exigegus]

Um, that's true of most shaft driven superchargers.

ummm , not at all true of shaft driven superchargers. they convert mechanical power to mechanical power.

less efficient than a turbo which converts waste heat to mechanical power, but there is no loss at conversion from mechanical to electrical[15%] and then back again[15%] and then a couple percent in having another belt loss.

They are useful for fuel economy in big fat cars, but serve no purpose in a performance car

 

[thebuzzard]

It is my understanding that our stock superchargers are also only active at WOT because in any other state the bypass is open?

 

[exigegus]

don't thinkit is WOT, but there is a bypass at low throttle

 

[steelypip]

I think an electric supercharger might JUST make it work... though I have yet to find out any information on charging times for the 48v pack

It's all about the duty cycles - track use is a very different use case than the stoplight drag race the system is designed for: Is the blower itself rated for 30-50% duty cycle? Can you use intelligent regenerative charging to quick charge the battery pack when braking for a corner? How long will it run off a full battery pack charge, and how many front straight accelerations does that work out to? Keep in mind that the 'turbo lag fixer' application is going to be very brief applications of very limited boost. Also keep in mind that, with the specs on the Aeristech unit at least, it's sized for a maximum of a 2L turboed engine, so a high RPM 1.8 is probably pretty close to its limits.