Anyone got one of these?

[Nausty]

http://dspmoto.com/powernow.html


just curious if anyone has one and if you do or have any experience with these, do they add a lot of power? If so is it worth it?

[ewalker302]

Everybody w/a 400ex has one-----the choke..

I saw these for sale a while ago & thought it was funny.

I think im gonna start my own company specializing in putting all different kinds of crap in peoples intakes & swear to them it will boost the hell out of their hp.

It seems to work for everybody else.

Some people think taking out their choke helps, this company is trying to convince you that putting that in is gonna help.

Rip off

:bandit:

[EvilJester400EX]

Some people may just want that extra chrome piece for bling bling. :rolleyes:

[skemp]

Some fancy animations. :rolleyes: Rip off.

[hondafox440]

My friend has one in his 250F. He claims it made a difference, but I don't believe it. Sounds like snake oil to me.

[stupid driver]

air will find the way w/ the least resistance. The vaccum created by the piston is sooo great, that a little air circulation because of the slide wont mean jack Sh|t. Im sure this product wont hurt nuthin on bottom, but it wont help much, if any. And on top end, forget it. Idk, everyone send me a few buks, ill buy it, and then we'll know if it works or not. :p

[Guy400]

Alright, I've got to ask this. They describe the air that tumbles around in the top half of the intake tract as "destructive air" and is disruptive in the production of horsepower. I'm no computational fluid dynamics engineer but this device doesn't seem to correct any of the problems they claim it does. I drew an extremely crude picture of a carb with this device in it and assigned letters to different sections to help explain what I'm getting at. The entire intact track is filled with air during operation. The blade in this Power Now device is not an air tight seal against the slide in the carb which means you're still going to get a collision of air at a 90 degree angle at Point D. But, because this area is partially sealed the air is going to reverse paths and head back upstream in an attempt to get underneath this Power Now blade (Point C). Now you've got another collision of air at Point B. Because of all this happening you've just moved the event at the carb slide that Power Now is trying to alleviate back to Point A.

Again, I'm no CFD engineer and I'd have to see a computer model to verify, but I think the information shown in the PN Flash video is wrong. When air is flowing from left to right they show the tumble of air against the carb slide to be rotating clockwise, this seems counterintuitive to me. Wouldn't the tumble of air be rotating counterclockwise, or with the flow of air? If you put a paddle wheel in a stream that was flowing from your left to right the paddle wheel would spin CCW.

Personally, I think any air tumbling in the upper half of the intake tract is negligible. When that throttle slide is opened that becomes an area of extremely low pressure and the air above the slide opening is then obviously higher pressure air. Because air will always attempt to equalize, this tumbling air will just be sucked under the throttle slide. This video they show wants you to believe that the air in the top half of the tract acts independently of the air in the bottom half.

[muff]

it won't work in my opinion

for it to properly work, you would need to have forced air going into the carb, then it would block the "disruptive air". however think of the engine like a vacuum, would the air that's not infront of the tube be disruptive? i dont think so.....point proven :macho

I also agree with guy and stupiddriver, there would be barely any air going over the devise at 1/2 throttle..why would it? theres nothing that would be pulling it up there except the gap that guy shows

[Dunlap]

I keep the choke in my 500ex for the same reason as this company except I do it because it causes a higher velocity at the needle jet which pulls the gas out of the carb harder and mixes it into smaller particals which burns quicker and makes more power. Taking the choke out only gains you about 5 CFM @ 15 inches of water and is only for top end. Your torque is what moves your atv from point A to B quickly not topend performance. Same thing happens when you put a big cam in with out the right compression piston, low torque topend power only and slower ETs.

[Colby@C&DRacing]

I like the powernow I have been talking to them for a while now about making one that fits the fcr carbs that we use on the 400ex. I have read many reviews and see countless dyno runs on fourstroke dirtbike using this product and like the results I have seen:)

[ridered86]

thats like saying that if you get a throttle body spacer for your truck your going to feel the rear wheel HP. its just a bunch of hyped up B.S. in my opinion.

now if you want real HP you can feel than you might want to replace your out of date, worn out muffler bearings:blah:

[MOFO]

Originally posted by Mickey Dunlap
I keep the choke in my 500ex for the same reason as this company except I do it because it causes a higher velocity at the needle jet which pulls the gas out of the carb harder and mixes it into smaller particals which burns quicker and makes more power. Taking the choke out only gains you about 5 CFM @ 15 inches of water and is only for top end. Your torque is what moves your atv from point A to B quickly not topend performance. Same thing happens when you put a big cam in with out the right compression piston, low torque topend power only and slower ETs.


Interesting point.

[Steve-o 400EX]

First off, it really doesnt matter b/c they dont make it for our quads yet. I can see good points from both sides though. I can see how it can work but from guy400's illustration, i can see how it might not work. The only way to find out for sure is when they make it for the 400, someone gets one and see's if it makes a difference.;)

[PHIL_B54]

Originally posted by Mickey Dunlap
I keep the choke in my 500ex .... Taking the choke out only gains you about 5 CFM @ 15 inches of water and is only for top end...

the guy i got my cam from said the choke stabilizes the air as it passes thru the carb, and that he has much better results leaving it in, specially for what little flow you would gain- granted that the cam i have favors mid more than top

so i would agree that the 400ex already has one of these installed in them..the choke

[MOFO]

Originally posted by Steve-o 400EX
First off, it really doesnt matter b/c they dont make it for our quads yet. I can see good points from both sides though. I can see how it can work but from guy400's illustration, i can see how it might not work. The only way to find out for sure is when they make it for the 400, someone gets one and see's if it makes a difference.;)



if you read this thread a little closer, you will find that the STOCK choke that comes on the 400EX acts the same as this.

Makes me feel better about leaving my choke in... :D

[MOFO]

Originally posted by PHIL_B54
the guy i got my cam from said the choke stabilizes the air as it passes thru the carb, and that he has much better results leaving it in, specially for what little flow you would gain- granted that the cam i have favors mid more than top




I think this information needs to get out... alot of people have/or are ripping their chokes out thinking they will get more performance out of it.

Originally posted by MOFO
if you read this thread a little closer, you will find that the STOCK choke that comes on the 400EX acts the same as this.

Makes me feel better about leaving my choke in... :D


You just don't know how to start your quad withouth the choke,, don't lie.....:o You know nothing about performance....:eek:

[MOFO]

Originally posted by Rico
You just don't know how to start your quad withouth the choke,, don't lie.....:o You know nothing about performance....:eek:

http://www.ricoracing.netfirms.com/Smilies/boid.gif

[member]

even if it did help that thing is a friggen rip off.. 100 bucks for 2 oz. of metal??they are screwed up.. that thing is so simple anyone could make it themselves for 10 bucks...

[Steve-o 400EX]

True that.

And as for MOFO, I took my choke out and did notice a agin by doing so. It wasnt huge but it made my quad a bit more responsive. I did read all the posts about how the chake acts as this, but that wont make me put mine back in. It starts cold and it will bearly turn over twice. :macho :muscle:

[ewalker302]

There's a sucker born every minute.

:bandit:

[chucked]

it CAN help, Ever put a carb on a flow bench?? I put on on it and I could actually get more cfms by sticking a pen at certain points, it was only a few but it did make a difference, Im gonna put my 400ex carb on it and see how much removing the choke helps.

[Dunlap]

I could sell you a new kind of spark plug and tell you it will make more power and you would see a difference. But in reality it may have been running rich before and it cleaned it up a bit. It has to do with the power of suggestion and different ways the motor was tuned in the first place. That is why you get so many different people saying so many different things.

[chucked]

Originally posted by Mickey Dunlap
I could sell you a new kind of spark plug and tell you it will make more power and you would see a difference. But in reality it may have been running rich before and it cleaned it up a bit. It has to do with the power of suggestion and different ways the motor was tuned in the first place. That is why you get so many different people saying so many different things.
im gonna settle the dispute, just give me a few more weeks, Ill do some dyno runs on my 400 with and without the choke and see what happens.

[cals400ex]

Originally posted by chucked
im gonna settle the dispute, just give me a few more weeks, Ill do some dyno runs on my 400 with and without the choke and see what happens.

i am interested to see that. i had mine out but i put it back in because i didn't notice anything. i know many people disagree, but mine starts better with the choke too so i put it back on.

I have the choke in and a 42 pilot jet. I love the way my quad starts on cold days. I hope he gets those results soon on the airflow with and without a choke.
I would also like to know what advantages there are with the 39mm fcr carb over the stock one. I just completed my 440 kit and need to take the next step in the never ending search for improved performance on a 400ex.;)

[chucked]

If all goes as planned I will be done it all in about 2 weeks.