Hi, I'm new to the group so first let me start by giving you guys a little backgroung, I started my association with atvs back in 1981 when I got my first atv, a 1982 ATC 185s, I was 12 and right from the start I got my hands on anything I could to get more power. Well the years pasted and I traded my 185s, that at the point was a 12:1 compression 205cc running in alcohol, laserII hi-lifht race cam, heavy duty valve springs, big als straight pipe header, ported polished with a 28 Keihin carb, 4" plus durablue axles and running on 20" goodyear rawhides (no suspension). Those of you that have been around a while are probably familiar with this set up. It was pretty quick too, we rode in only sand and blacktop so our bikes where stripped down to be very light, aprox 250lbs. It was very competitive and on the street would beat stock and slighly modified ATC250Rs (the air cooled 5 speed 1984-1985 models.) Later on I traded it for a atc200x and then a 1986 ATC250R(talk about fast.) Any the point is back when I had my 185s I was also really into turbo cars and one day came up with an idea. I figured that if I could forced air into the carb and feed it more gas I would get more power. So I created my first forced induction system, I would say it must have been 1983. What I did was ducttape (this was an experiment) an 8" large-opening funnel to the side of the tank, I replaced the airbox, it had been removed to save weight and breath better, I sealed the drain holes on the airbox and connected a 2" fishtank hose to the air box with the filter in place(I was only 14 years only).I also richened the carb a little to handle the extra air. I took the 185s out to the asphalt strip that ran through the park and gave it for a test run. All I could say was WOW! It looked stupid but what a kick it got when I shifted into 3rd, the thing would wheelie on 5th with an automatic clutch! As soon as it got moving and the wind picked up the engine would scream. It was too impracticle to ride around with but I must have picked up an extra 4 hp, pretty good considering a stock 185s had 12.
Now I just bought a house and finally have a place to keep an atv, of course it will be a 400ex. I was thinking with the open area behind the front bumper you could easied fit some kind of funnel/induction system as long as you are not riding throught water. This would be a good set-up for dry trail and dune riding. Other things to note is that the low-end torque got very strong when I ran the test (in comparision to an open air Uni-filter.)After some research I discovered that open airfilter systems loose torque and HP in lower rpm in comparision to snorkle type systems, most dyno tests will confirm this. I think if the ATV is really fast you might need to set up some kind of wastegate to get rid of the extra air when you let go of the throttle at high speed, but that should be easy. Also note this kind of thing is currently being used in crotch-rockets, see the suzuki GSRX line. I would love to try this on a dyno but you would need to have a 60 MPH wind blowing at the bike to see if it really works.

P.S. I hope no one take offense to this, but it is really annoying to see these long signatures discribing what machine/s you have/had, every nut and bolt, what kind of air you use in your tires. I don't think anyone really cares and you are making simple posts pages and pages long.

 

I agree with you on the long, annoyingly repetitive signatures, robg.

Now, no offense intended likewise, a suggestion for you:

Consider breaking up your posts into paragraphs.

Separating a substantial post, like yours above, into different points, thoughts, and topics makes it much, much more interesting and easier to read.

Diogenes

Something like:

Hi, I'm new to the group so first let me start by giving you guys a little backgroung.

I started my association with atvs back in 1981 when I got my first atv, a 1982 ATC 185s, I was 12 and right from the start I got my hands on anything I could to get more power.

Well the years pasted and I traded my 185s, that at the point was a 12:1 compression 205cc running in alcohol, laserII hi-lifht race cam, heavy duty
valve springs, big als straight pipe header, ported polished with a 28 Keihin carb, 4" plus durablue axles and running on 20" goodyear rawhides (no suspension). Those of you that have been around a while are probably familiar with this set up.

It was pretty quick too, we rode in only sand and blacktop so our bikes where stripped down to be very light, aprox 250lbs. It was very competitive and on the street would beat stock and slighly modified ATC250Rs (the air cooled 5 speed 1984-1985 models.) Later on I traded it for a atc200x and then a 1986 ATC250R(talk about fast.)

Any the point is back when I had my 185s I was also really into turbo cars and one day came up with an idea. I figured that if I could forced air into the carb and feed it more gas I would get more power.

So I created my first forced induction system, I would say it must have been 1983. What I did was ducttape (this was an experiment) an 8" large-opening funnel to the side of the tank, I replaced the airbox, it had been removed to save weight and breath better, I sealed the drain holes on the airbox and connected a 2" fishtank hose to the air box with the filter in place(I was only 14 years only).I also richened the carb a little to handle the extra air.

I took the 185s out to the asphalt strip that ran through the park and gave it for a test run. All I could say was WOW! It looked stupid but what a kick it got when I shifted into 3rd, the thing would wheelie on 5th with an automatic clutch!

As soon as it got moving and the wind picked up the engine would scream. It was too impracticle to ride around with but I must have picked up an extra 4 hp, pretty good considering a stock 185s had 12.

Now I just bought a house and finally have a place to keep an atv, of course it will be a 400ex.

I was thinking with the open area behind the front bumper you could easied fit some kind of funnel/induction system as long as you are not riding throught water. This would be a good set-up for dry trail and dune riding.

Other things to note is that the low-end torque got very strong when I ran the test (in comparision to an open air Uni-filter.) After some research I discovered that open airfilter systems loose torque and HP in lower rpm in comparision to snorkle type systems, most dyno tests will confirm this.

I think if the ATV is really fast you might need to set up some kind of wastegate to get rid of the extra air when you let go of the throttle at high speed, but that should be easy.

Also note this kind of thing is currently being used in crotch-rockets, see the suzuki GSRX line. I would love to try this on a dyno but you would need to have a 60 MPH wind blowing at the bike
to see if it really works.

P.S. I hope no one take offense to this, but it is really annoying to see these long signatures discribing what machine/s you have/had, every nut and bolt, what kind of air you use in your tires. I don't think anyone really cares and you are making wimple posts pages and pages long.

 

I think that idea might work.. I don't know about all that dust that will be rammed into the airbox, that might not be good, but other than that it sounds like a good idea! I thought about doing that but the dust gets kinda bad in the summer and I decided on not doing that.

 

I too have thought about this, but when I see how much crap makes its way to the airbox, even with the very restrictive stock snorkel...I quickly forgot everything about it. It does work very well for the sportbikes as you said. The Kawi ZX6R puts out 100hp on a dyno, and is said to gain 20hp (20%!) when going for more than I can't remember what speed.

For the big signature thing...I prefer when you see what people ride, cause when they ask questoins, you see instantly if you can help or not. Say I see in a signature 400EX and the guy says I want power, than there's nothing anyone can do ...ahah. Really, I hate reading posts when the guy asks if he did this right or wrong, and you can't find anywhere what his ride is...oh well...doesn't change much though. For me, the longest loadings are for the page with all the topics...

Just a question...is the air 1 foot above my head clean or dirty? I could put a snorkel

 

Personally i hate the page long signatures but i also think its a good idea of having a small sig so everyone will know what you ride and the major mods.

As for the "forced induction"...(ram air)
The reason this works so good on sport bikes is because of the speed you reach. You dont actually create a real ram air affect (like what a supercharger/turbo does) until you are well over 100 mph. You do add a certain amount of air "pressure" in the air box which will add some power but for it to work right you need a somewhat straight shot into the airbox....which you can't do on most quads because the airbox is in the rear. You'd have to route the ram air "tube" over or around the engine and into the airbox. If you've ever taken a good look at a 300ex or 400ex you'd see that its a tight fit in there to begin with. With the ram air tube so close the motor they would probably get very hot which would in turn heat the air going through it which would then cause a negative effect. Cold air is more dense then hot air, which means cold air makes more power. (with the right jetting)
The biggest problem i see is the fact that even on the cleanest trails you would get tons of dust and dirt in the airbox.

 

Ram air induction in an ATV is not a good idea. You only gain HP when the machine is moving very fast. I don't think your 400ex will go fast enough for it to make an improvment that outweights the risk to your motor and hassle of dirty filters. Probably the 1st 10 minutes of your ride will be good but then your filter would be so dirty that it will be running too rich and your motor will bog down.

You would be better off fitting a small turbo in that space you describe. It would be a much better forced air system then the simple Ram. It would also be easier to tune in. The potential problem would be in how to keep the intercooler clean.

However if you would read those signatures that you detest so much, you would probably see that the common school of thought in adding power to a quad does not lay in forced air induction. Sure it would be nice to duct tape a funnel on a quad and run some fish tank hose, but I really think you get what you pay for.

Forced air systems are very rare on ATVs. This is due to factors including cost, complexity, added weight and poor realibility in the conditions that most ATVs are used in. This doesn't mean that it can't be done, just that it might be more practical to use a tried and true method of adding HP.

You can spend an insane amount of time and money making a Quad go faster. You could set up a turbo system with a huge intercooler and a water sytem set up to spray water on the intercooler to keep it cool and clean. A MAF sensor hooked into a fuel injector system and timing adjustment circuit to keep it all running perfect. You could even add a NOX injector on top of that for even more kick. The headaches involved on such a system though, wow I don't even want to think about it.

Reread some of those signatures again, you will see the proven path to power.

 

I agree with him about the turbo. If you really want to make something special and unique i would go with a turbo. I've seen a few go karts with custom turbo setups on them. Because of the size of the motor you'd have to find a turbo small enough so you can get it spinning fast enough.
I dont think it would be that big of a deal with keeping the intercooler clean because many quads have radiators and they stay somewhat clean (or at least clean enough) during normal use.
By far the biggest problem with mounting a turbo would be wear to actually mount it. It would have to be up front somewhere right near where the exhaust exits the motor but it couldnt be too close to anything plastic because those turbos get VERY hot.
Finding a place for the intake tube plumbing would be a whole other problem all together. You would have to mount the air filter up front near the intercooler so you dont get dirt/debris in the turbo.
Another problem would be that most turbos require oil pressure to operate which would mean you'd have to tap into the motors oiling system which could cause troubles in itself.
Ahhhh, it wouldn't be easy but it would be wicked and very unique.