Piston Super Charger operation

Valve operation in my piston supercharger used on a Uniflow 2 stroke experimental engine. Vid of the engine running to follow.

Category:

Education

Tags:

• Briggs
• and
• stratton
• piston
• supercharger

[muhammadisasissy]

Neat experiment but you will not get much air into the cyl. to pressurise (or out) with the little valves & all the turns in the ports. The concept is not new. For MANY years people have used one or more cyls. on a multi cyl. engine as a compressor. I have a friend who has a 3cyl rotary aircraft engine from the '30's with one cyl. set up as compressor. Really neat. Anyway, keep up the work & good luck.

[ChargerMiles007]

@muhammadisasissy

Yes, you are right, this is big and heavy, and doesn't put out a whole lot of air, but it was the simplest way I could figure out, to get the job done. A mini Roots is a hard item to come by at a scrap yard! :)

[muhammadisasissy]

@ChargerMiles007 Try a smog pump.You can buy Dick Datson,s book "Supercharging Small Engines" for about $15.00 on ebay. They are the Gator Supercharger guys. Tells how to build a blower for about $100.00. Easy and you only need simple hand tools and some parts from a Toro leaf blower. Too Cool.

[ChargerMiles007]

@muhammadisasissy

Hey, thanks for sharing that info! :)

I will have to look into that.

I will have to keep my eyes open for leaf blowers at the scrap yards!

[ChargerMiles007]

@skylartjsayers

Yep, the Centrifugal blower has to spin fast to do the job!

I don't know how long it would survive revving up and down a lot, as the rpm change would put a lot of stress on the blades. Aircraft used a torsion spring or a fluid drive to help out with that. A Turbo-charger gets rid of that problem, but adds a few others.

[skylartjsayers]

@ChargerMiles007 If your machine idles at 1500 and it is geared 6:1 then your charger is spinning at 9000 rpms. touch the throtle and bring it to 3000+ rpm for a brake torque (I am using it for a drag application) and you double the chargers rpms to 1600rpms. Lay on the throtle and watch your charger climb 6x your rpms

[skylartjsayers]

@ChargerMiles007 Do me a favour, if you have a larger vaccum (as I have a larger motor) turn it on, put your hand over the exhaust. keep it there and turn off the machine. Even the low rpm push out air. The key you engine is having air assisted in insted of sucked.

[skylartjsayers]

@ChargerMiles007 But I like your concept. Maybe if you had a light wieght pistion pump manufactured it would be ideal for an application but using a cast iron or aluminum block head and crankshaft is not nessiarry ideal for commpressing air beacuse it was made for a heavy duty application - harnessing an explosion. Maybe a pump off an air compressor would work if were lighter. idk

[skylartjsayers]

@ChargerMiles007 A cvt engages at almost 4000 rpms when the engine is tuned for lets say 10000 rpm. So the boost is essential at 4000 rpms. 4000 rpm with the charger geared at 6:1 has you fan pushing at 24 000 rpms. Worst case sceneario you dont recieve significant boost till your highend. It is better than no boost and I think the shear wieght reduction of my concept makes it ideal. It wieghs as much as a baseball.

[skylartjsayers]

@ChargerMiles007 I am using a 2 sroke... higher rpms and the gearing is key. The fan blows as long as air is going in and it is turning which at low or high rpms is beter than pure atmospheric pressure. On vehicle applications the boost has to build with rpm.