Mini Turbo

[AlexRSS8]

Better idea, Mount a fan onto the motor (With a gap) a 120mm 7000rpm+ Fan, just run it off a battery and switch (i use simple circuits for everything), and powering fans not a problem, Powered an old 4V 3000rpm fan with a 9v, got up to 6000rpm.

Still, there'd be no point, i mean the fan would do nothing at all, unless you hooked up a cooling system with mini radiator and fan (now thats an idea) but that'd be to much stuffing round if you ask me

 

[Q5Quint]

I put a turbo on my car once.... it worked out pretty well if you just go through all the right sizing calculations.

I am looking at about 10-25 lbs/min of airflow for a 2.5 liter 4 stroke at 14psi above ambient....


http://www.e30tech.com/forum/showthread.php?t=43911&highlight=quint+turbo

You could do it pretty easy on the little 80cc if you spent the $$.... but bang for the buck you can get a really decent and much larger displacement engine for a lot cheaper than putting a turbo on the happy time?

The calculators to do the math are out there... I would use them first before spending the money strapping something to your engine. There were some motorcycles in the 80s I feel that came with turbos.... and you can still get tiny cycle turbo kits.

I use this often: http://www.turbofast.com.au/freesoftware.html

Goodluck!
-Q

 

[duivendyk]

It takes SERIOUS power to do any good at all,something like 100W plus.The best computer fan has less than 1/10th of that.Forget it, unless you have a hankering for 'futile persuits'.

 

[nadroj]

I put a turbo on my car once.... it worked out pretty well if you just go through all the right sizing calculations.

I am looking at about 10-25 lbs/min of airflow for a 2.5 liter 4 stroke at 14psi above ambient....


http://www.e30tech.com/forum/showthread.php?t=43911&highlight=quint+turbo

You could do it pretty easy on the little 80cc if you spent the $$.... but bang for the buck you can get a really decent and much larger displacement engine for a lot cheaper than putting a turbo on the happy time?

The calculators to do the math are out there... I would use them first before spending the money strapping something to your engine. There were some motorcycles in the 80s I feel that came with turbos.... and you can still get tiny cycle turbo kits.

I use this often: http://www.turbofast.com.au/freesoftware.html

Goodluck!
-Q

Thats a sick e30 you got there, I had a e30 318is for a while.

 

[juliman]

hey guys how bout this, instead of a fan, how about an old fire extinguisher bottle? etc filled up with compressed air and you have a valve which blows the air into intake(like the fan but compressed air is compressed(duh) so it would have more effect, but probably lean motor out, u could set carb right though) just an idea lolz

 

[Clotho]

The Chinese engines are piston ported engines. They have no valves. No way to keep the boost in. You could put the biggest turbocharger/supercharger in the world on there and it won't do a thing until you solve this problem.

One solution was to use an expansion chamber to help hold the boost in. The only problem with this is that you only get a boost condition at the range the expansion chamber is tuned for. This makes for an extremely peaky powerband unsuitable for driving on the street.

This idea comes up on a regular basis and it has been discussed many times before. If you do some research you will find those discussions.

 

[DougC]

The Chinese engines are piston ported engines. They have no valves. No way to keep the boost in. ...

If you had a four-stroke and wanted "boost", one way to try would be to hook up a vacuum cleaner blower between the intake and carb, like a supercharger.

Most vacuum-cleaner blowers seem to operate normally at speeds between 10 to 15K rpms and most of these small engines top out at around 5000-6000 RPMs, so the 3:1 gearing needed isn't unrealistic.

The last problem is that you're trying to get more power out of the engine that it's really designed for. You'd need a pressure-blow-off valve to prevent the thing from running too much boost at higher RPMs. The pressure that an axial fan delivers increases as the RPMs it spins at goes up.

A blower could still be useful I think, because with it you could push the torque curve lower into the engine's RPM range. And of course it would look nifty as well.

Most vacuums now are probably made of plastic, but I saw a old Kirby vacuum once that had a cast-aluminum body and impeller....
~

 

[Clotho]

A 4 stroke has valves so it is possible to boost a 4 stroke.

Do not confuse a 'fan' with a 'compressor' however. A fan will move air but it won't create boost. Every vacuum cleaner I have seen is of the fan type.

When you add more air under boost you have to add more fuel as well. If you do not you will create a lean condition. For this reason the compressor is usually placed before the carb in circuit as opposed to in between the carb and the intake.

 

[motorpsycho]

everyone is right, you would need a compressor to build boost. a fan will do nothing but move the air around. For a turbo to work effectively, you need the entire intake tract to be sealed except for where the air filter is.
why mess around with the fan idea? if you want a power boost, throw a nitrous kit on it.

 

[andynogo]

Ooh, ooh, I know! How about one of those 4WD air compressors? That compresses air, so chuck a 12V car battery on a rack on the bike, get the biggest compressor you can find and fit it instead of the air filter using plastic piping. It would look really good and make a supercharger type noise as well- especially if you put some sand in the bore of the compressor first to make it squeal.

Might work about as well as the electric supercharger kits for cars on ebay.

Can't believe this thread has been going so long- didn't start on 1st April, did it?