Ok so I was browsing Summits catalog looking at super chargers and noticing the extremely high price of around 2k. Then I had an idea. A supercharger just forces more air into a given amount of space, so couldn't you achieve the same thing with an electric leaf blower from home depot? They go for around $75 for a good one. I doubt it could work very well for very long atleast, but I have read some very interesting posts on here and thought maybe someone might have tried it.

 

i am pretty sure it won't move nearly enough air for very much RPM.

it *might* give you a little something off idle, but about that i bet it would just be a big restricion. take that $75, put it in a jar, and start saving for headers

 

hehe, those blowers claim to be able to go 200 mph. My only question is, is that how fast the air is moving, or how fast the motor is spinning. Of course they should put rpms if it is how fast the motor spins I guess. Maybe if I can get one really cheap at a garage sale I might try it

 

Well they do have stuff like that on Ebay....electric turbos or something; But they only work to a certain RPM and then are an obstruction.

If you really wanted a homebrew cheapo boost, find an old worn out turbo and rebuild it..........OR......cast your own blower/turbo. There's a whole lot of sites that cover homecasting. I'm even designing a two-stroke 3 cylinder go-kart engine that I'm going to cast the block for.:hail:

 

Jackal,

Would you mind posting a few links? I have been interested in that type of stuff but havn't been able to find any good sites on it.

 

it isn't a problem of MPH it is a problem of CFM.

at 2000RPM, the engine requires twice the air it does at 1000RPM, and so on so forth.

example (hopefully my math skills are up to date)

at 3000RPM, for complete cyl. fill, at 305 requires about 255CFM of air, at atmosphic presure. for any amount of boost, you need more than that. to go to 5000rpm, it takes about 425CFM, that is assumint 14.7:1 A:F, at WOT it would actualy take a little less air, since you are at about 12.5:1.

(not those figures are JUST what it takes to fill the cylinders) for boost it would take more than that. i highly doubt a leaf blower can more any near that amount of air. let think of it this way.

for a leaf blower to make 425 CFM (no boost) assuming it fan/pump whatever, moves at 10,000 RPM it would have to displace about 73.5 cubic inches of air PER revolution. that is also assuming that a leaf blower is a compressor, they may be nothing more than a fan, and completley unable to produce boost, but if they are a pump, it would work, if you could displace that somewhere about 73.5 ci of air per revolution. that is also assuming that it isn't HEATING up the air. if you are heating it up, to make the same power level, you would have to displace even more air.

 

well they have a vacuum on them so I think it would have to be a compressor of some sort. Also I was thinking about still leaving the stock snorkle and just add another hole to force more air into the tbi unit. Although I am not sure if that would work cause it might just force more air back out the snorkle.

 

correct, to effective make it a 'supercharger' you have to have pressure. and if you do it that way, all you are doing is moving hot air in there, you might actualy lose power doing it that way.

like i said, save you money, and buy headers.

 

That’s the key right their. That’s why those fans on eBay will do nothing. You have to have a compressor to produce boost, a fan won't. Go search the power adder board, their are quite a few threads on leaf blowers and electric fans.

 

Some hillbilly already beat you to the punch.
See the last post of this thread.
https://www.thirdgen.org/techbb2/sho...ght=leafblower

Best-
S-D

 

hehe, ok now that I know someone else has tried it I don't have to the only other thing I found interesting was this.

<b>FACT: the Fan unit (or leaf blower, and it does blow the heck out of leaves on your driveway too, but a little price to do that), produces over 500 cfm. out of a 3" diameter, that is a flow rate of over 120 mph. this is generated out of a never seen before, impeller that is specifically designed to absorb the hp of the electric motor at high currents.</b>

using that ratio that would mean those leaf blowers that claim 200 mph out of the 3" hole would be moving around 830 cfm. Assuming that those numbers are correct. That is a lot of air. Assuming that those numbers are correct of course Wish I could see a dyno sheet for that guy who actually did it

 

Fact: if it is a fan unit, it will jack execpt heat up the air. fans cannot produce any boost what so ever.

 

One of the things most people dont even realize with supercharging and turbo charging is that the main by-product of compressing air is heat.
Both forms of forced induction are subject to adiabatic losses cause by heat.
I will give a few examples.
When Vortech first introduced the A Trim super charger. It was designed to produce 5-6lbs of boost with a 3.3" pulley.
Guys would substitute a 2.75" pulley to spin it faster and make between 8-10lbs of boost. The result most often was blown head gaskets. Guys blamed it on too much boost which is partially true.
It wasnt the actual boost the cause the head gaskets to fail. It was the hot charge of a blower being operated outside of its efficient range.
Turbos are the same way. You can take a given turbo car such as a Grand National which runs between 14-16lbs of boost when stock. Guys will throw in the needed fuel systems modifications and add race gas and try to run 25lbs of boost. Problem is the turbo looses efficiency over 20-23lbs. In small terms, you start blowing hot air. Intercooling wont help cover up compressor inefficiency. Hot air charges result in detonation and detonation is what kills head gaskets and other hard parts.
Garret and other turbo manufacturers release compressor maps which show a given compressors efficienct range. Superchargers are the same way. The difference is that many Supercharger manufacturers have their formulas based on compressor rpm when figuring out pulley diameters and ratios.
In ending, forced induction requires careful calculations to pick and efficient turbo/super charger. It isnt a matter of bolting a leaf blower on and running ridiculous times. If it was, there would be a lot more guys running out to Sears or Home Depot to "boost" their car.

 

Sure nuff'

http://www.frii.com/~katana/castindex.html

Thats a good starting place to go from. Basics and what-not.

If you really are going to try something like a turbo fan or compressor, look into the material details quite extensively. Material science is the greatest obsticle in the pursuit of turbine technology.

If you need any help, just let me know, I have alot of engineering knowledge :lala: