Go Back   DIY Go Kart Forum > Building Plans And Advice > Engines & Clutches

Notices

Closed Thread
 
Thread Tools Display Modes
  #41  
Old 09-19-2008, 07:08 PM
gocartkid's Avatar
gocartkid gocartkid is offline
Bad Attitude
 
Join Date: Apr 2008
Location: CT
Posts: 329
Thanks: 3
Thanked 8 Times in 7 Posts
Default

Quote:
WHY DONT YOU JUST!

put nitrous on your kart? ive seen it done, in fact i got pics.
Quote:
Originally Posted by jr dragster Tyler View Post
I would seriosly drop the epoxy, Pipe and flywheel method and look for safer performance enhancments! Like seriosly whats a cam and some porting gona cost?
I agree with both. I mean they have NOS kits for Harleys and the like, and isn't NOS the poor man's power adder? Sounds like a good place to start to me. I have an extra bottle lying around what do I need to do?
__________________
Build it... drive it... break it.... fix it... repeat....
  #42  
Old 02-21-2009, 10:50 AM
Stonecutter Stonecutter is offline
Junior Member
 
Join Date: Feb 2009
Location: Chicago
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Default

The NOS kits are big bucks! I went to Holley yesterday and their 100cc kit is out of our price range. ($600+)
A blower will work and won't limit you to an 8 second burst (which you get with NOS) if you build it right. Plus you can even rig up a belt engager so you can turn it on or off as needed.
Things to consider are....
Pressurized air will blow fuel back up the carb unless you have a pressure tube going to the gas tank or fuel bowl (depending on what type of carb you're using). A pressure tube going from the blower outlet to the gas tank or carb fixes that. If after starting up the engine & blower and the engine dies or fuel comes out of the carb, it's because the fuel system isn't pressurized.
If you'll be running under hot and humid conditions it offsets the benefit of the blower as the blower will tend to heat up the compressed air. In that case you can build a small inter-cooler. One can be made with a can of ice, coiled copper tubing, a small pump and a surplus heater core. Intercooling works good even when you don't have a blower. Cooler air is denser, and a denser mix equates to more hp. And that's primarily what NOS does. The nitrous itself isn't flammable. It cools the intake charge, making it denser.
If you want some plans for a supercharger, send me an email or PM. Our design will be different, but the plans go over all the important things you need to know if you're going to make your own.
  #43  
Old 03-19-2009, 11:38 PM
blank blank is offline
Junior Member
 
Join Date: Mar 2009
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Maybe try one of theses? Electric Turbo just put less voltage to decrease the pressure it would make...or rig the the blower up to the engine instead of using a 12v supply...
  #44  
Old 03-20-2009, 01:47 AM
modelengineer modelengineer is offline
Lord of the noise
 
Join Date: Apr 2008
Location: Sydney, Australia
Posts: 1,608
Thanks: 2
Thanked 100 Times in 94 Posts
Default

Those things are the biggest joke. They don't work and they make you lose power. Also, even if it did work, it would be an 'electric supercharger' and not a 'turbocharger'.
__________________
Andrew
GS500F powered...
  #45  
Old 03-20-2009, 04:15 AM
BradenM BradenM is offline
Etre Et Durer.
 
Join Date: Dec 2008
Location: In a big jar of Nutella, nom nom nom
Posts: 604
Thanks: 17
Thanked 30 Times in 29 Posts
Default

Can anybody say....GIMMICK?
__________________
Quote:
Originally Posted by gokartcrazy View Post
omg i almost poopied my man thong i didnt know my brother wore thongs too
  #46  
Old 03-20-2009, 08:40 AM
Stonecutter Stonecutter is offline
Junior Member
 
Join Date: Feb 2009
Location: Chicago
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Default

FYI.....
A friend just ordered a small electric (120v ac) leaf blower on ebay and gave it to me. It's really small and I was able to take it apart and separate it from the electric motor pretty easily. The trick is to cut or chisel away the armature from the shaft and it will leave you with around 4 or 5 inches if shaft to work with. I picked up a couple of extra high speed bearings and now I have to make a bracket to hold the blower body and bearings. I have a lightweight 2" aluminum pulley which will be attached to the shaft and a 5" pulley that will go on the jackshaft to drive the blower. As long as the bracket that holds the blower and bearings is strong enough to hold it all together under load, I figure it will at the minimum force enough air into the carb to give a performance boost. It remains to be seen if this will actually create true pressurization or not.

We're going to bench test it with an electric drive motor and I'll put a low pressure gauge on the capped-off output tube to see if we register any psi when we get it up to speed. For a small cc engine you only need to generate a few psi. When I was hot-rodding V-8's we typically ran about 10-20 psi of boost, so anything up to 4 or 5 psi on a small engine should "theoretically" work.
The thing to consider when forcing air into your intake is to remember that carbs work with a vacuum or venturi principle. If you do get true pressurization, gas will be forced back up the carburetor, fuel bowl, or vent tube unless you pressurize it as well. The way to do that is to tap off a small line from the blower to a fitting you put on the vent tube, or you can pressurize the gas tank by running the pressurization tube to the gas cap, all depending on what kind of carb you have. The main idea is that the air pressure in the carb and the incoming air have to be equal or gas won't flow into the engine.

It'll be a couple of weeks before we get around to testing whether we can build up workable pressure with the leaf blower parts because we're still in the middle of fabricating our chassis. The leaf blower cost $14 and the bearings were under $10 at American Science & Surplus so even if it doesn't work it will be an interesting experiment. Everything will hinge on whether the leaf blower can actually generate couple of psi of boost or not.

Oh BTW..... in my previous post I noted that NOS systems made by Holley for single cylinder small engines was cost prohibitive ($680). Since then one of the guys found these cheapo one-shot disposable systems on ebay for real cheap. We're ordering one just for giggles to see how they work. They're supposed to give you a 8 second power shot of NOS.
http://cgi.ebay.com/ws/eBayISAPI.dll...m=220136864299

Will report back later on whether the home made supercharger and the NOS system work or not.
  #47  
Old 03-20-2009, 01:21 PM
blank blank is offline
Junior Member
 
Join Date: Mar 2009
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Quote:
Originally Posted by modelengineer View Post
Those things are the biggest joke. They don't work and they make you lose power. Also, even if it did work, it would be an 'electric supercharger' and not a 'turbocharger'.

But look at the different application. Yeah, it won't do much on a car, but this on a small engine could work wonders. A simple 120mm computer fan can put out over 100 cfm, with the right type of blower you could easily get a few psi boost...
  #48  
Old 03-20-2009, 01:54 PM
Scorch3 Scorch3 is offline
Senior Member
 
Join Date: Nov 2008
Posts: 164
Thanks: 3
Thanked 4 Times in 4 Posts
Default

Quote:
Originally Posted by blank View Post
But look at the different application. Yeah, it won't do much on a car, but this on a small engine could work wonders. A simple 120mm computer fan can put out over 100 cfm, with the right type of blower you could easily get a few psi boost...
You have to keep in mind that those cfm ratings are often for a large open area, and not the inside of a small pipe. At the same time you have to create an actual pressure boost otherwise the fan will be doing little more than obstructing air flow.

Also when you talk about running a supercharger off the engine you will need to create at least a couple psi of boost to make up for the power lost simply by driving the supercharger. Efficiency is key with low boost superchargers in order to create any actual performance increase so cobbling something together at home likely won't work.
__________________
01011110 00100000 01100101 01110000 01101001 01100011 00100000 01110000 01101111 01110011 01110100 00100000 01011110
  #49  
Old 03-20-2009, 03:57 PM
jr dragster T's Avatar
jr dragster T jr dragster T is offline
Senior Member
 
Join Date: Jul 2007
Location: Cold place
Posts: 3,966
Thanks: 18
Thanked 170 Times in 153 Posts
Default

Nitrous is the easy way out
  #50  
Old 03-27-2009, 04:15 PM
caminin21 caminin21 is offline
Junior Member
 
Join Date: Mar 2009
Posts: 5
Thanks: 0
Thanked 1 Time in 1 Post
Default

another option might be to alter a water pump from the junk yard. might be able to hold up to the rpm's better.
  #51  
Old 03-27-2009, 04:38 PM
l0ll00l's Avatar
l0ll00l l0ll00l is offline
Member
 
Join Date: Mar 2009
Location: San Antonio, TX
Posts: 81
Thanks: 0
Thanked 6 Times in 6 Posts
Default

I'm not sure I'd be too ready to trust running a water pump without water in it. If I'm not mistaken, the seals and bearings are designed to be cooled by the water that passes through. I could be totally wrong, but I also don't see it capable of producing high enough CFM under pressure.
  #52  
Old 03-27-2009, 10:13 PM
Buick455 Buick455 is offline
got any pictures of it?
 
Join Date: Feb 2009
Location: Florida
Posts: 185
Thanks: 3
Thanked 25 Times in 25 Posts
Default

I have see (in a forum) someone use a smog pump, but I can't find any pictures...
  #53  
Old 04-12-2009, 08:39 AM
sideways's Avatar
sideways sideways is offline
Unfinished projects king.
 
Join Date: Feb 2009
Location: Perth, Western Australia
Posts: 1,501
Thanks: 50
Thanked 164 Times in 115 Posts
Default

if you put the carby before the supercharger then you wont have a problem

like have the things on the inlet part in this order

airfilter-carby-supercharger-engine

otherwise known as the suck through system, because the supercharger is sucking through the carby.
  #54  
Old 06-28-2009, 08:20 AM
Rotore Rotore is offline
Teh SPIK
 
Join Date: May 2009
Location: Caguas, Puerto Rico
Posts: 1,663
Thanks: 23
Thanked 25 Times in 24 Posts
Default

tyler it'd be cooler having a f/i cart lol

BTW if you want this would be perfect for a supercharger since its already sucking in air from one end and blowing it out through the other, just have to mod it a lil bit: i got it off a vacuum (lol i know) here are some pics:

question tho would a 399cc 11hp briggs be enough to get a small turbo to spool up?
Attached Thumbnails
HPNX0234.JPG   HPNX0233.JPG  

HPNX0231.JPG   HPNX0230.JPG  

HPNX0226.JPG  
__________________
"No one is going to open doors for you your whole life, sometimes you have to open the dor yourself." Eddy
  #55  
Old 06-29-2009, 06:07 AM
sideways's Avatar
sideways sideways is offline
Unfinished projects king.
 
Join Date: Feb 2009
Location: Perth, Western Australia
Posts: 1,501
Thanks: 50
Thanked 164 Times in 115 Posts
Default

mitsubishi make tiny turbos for 250cc + engines, from memory the smallest one is called the TD015, iv got heaps of info on them somewhere in the deep depths of my copmuter, il see if i can find it, they come up on ebay every now and then for about AU$500 brand new as for the electric turbos i think they may be worth a try because u've got to remember that we're using engines less than a tenth of the size, maybe try and run them on 24v or sumthing, that would make twice the revs thus twice the air pressure
  #56  
Old 06-29-2009, 06:20 AM
sideways's Avatar
sideways sideways is offline
Unfinished projects king.
 
Join Date: Feb 2009
Location: Perth, Western Australia
Posts: 1,501
Thanks: 50
Thanked 164 Times in 115 Posts
Default

http://www.mhi.co.jp/en/products/det...put_range.htmlhttp://www.mhi.co.jp/en/products/det...ification.html heres 2 links to mistubishis site with sum info

just remembered! peugeot make a supercharger for one of thier scooters, i think its called the jetforce? its a 125 anyway. it worked quite well aparently
  #57  
Old 06-29-2009, 09:52 AM
frederic frederic is offline
The Junk Man
 
Join Date: Jun 2009
Location: New Jersey
Posts: 385
Thanks: 7
Thanked 43 Times in 37 Posts
Default

Having done many automotive experiments with turbocharging and supercharging over the years, there are two key features that a hair dryer, leave blower and a Briggs "fan flywheel" are missing:

1. Seals (or tight enough clearances where the boundary layer inside the housing acts as a seal which is the case in supercharging and turbocharging)

2. Compression chamber - remember that a turbocharger's housing is shaped like a scroll, and if you look carefully you can easily imagine what it's shape would be if you could "unroll" that scroll housing - it would be a cone.

To achieve pressure over atmospheric pressure (14.7psi) the supercharger and turbocharger "fans" need to spin in the 65,000 - 100,000 RPM range. Below that you're not really building enough pressure to make fabricating a custom system worth the effort. In fact, most super/turbochargers are highly inefficient at lower RPMs because they "leak". They use the boundary layer of the air against the inner surface of the scroll housing as a seal - the air is in "sheer" in a sense.

No seal, no pressure. It's really that simple.
  #58  
Old 06-29-2009, 10:17 AM
mike75925's Avatar
mike75925 mike75925 is offline
thinker and tinkerer
 
Join Date: Jun 2009
Location: Alto, tx
Posts: 1,753
Thanks: 34
Thanked 54 Times in 54 Posts
Default

ah but what of ducted fans?
  #59  
Old 06-29-2009, 10:53 AM
ed1380's Avatar
ed1380 ed1380 is offline
Banned
 
Join Date: Mar 2007
Location: ATL, GA
Posts: 1,182
Thanks: 9
Thanked 26 Times in 26 Posts
Default

http://cgi.ebay.com/ebaymotors/Elect...Q5fAccessories
  #60  
Old 06-29-2009, 11:06 AM
l0ll00l's Avatar
l0ll00l l0ll00l is offline
Member
 
Join Date: Mar 2009
Location: San Antonio, TX
Posts: 81
Thanks: 0
Thanked 6 Times in 6 Posts
Default

Quote:
Originally Posted by ed1380 View Post
Dear god.. Please tell me no one has bought one...
Closed Thread

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 03:44 PM.