YES,it fit the direct hit spark amplifier,you must specs the year and model when ordering and they will sent you the one that fit with the right wire,you'll see quicker acceleration,quicker throttle response,more torque and hp,better fuel economy,easier starting,cleaner emissions.

http://www.directhits.com
or you can order it from www.lo-ko.com

do you known fitch fuel catalyst?
i use their products and it give amazing torque gains and hp.
just drop it in the gas tank.
ckeck this out,
www.fitchfuelcatalyst.com

 

Walexa...HPD called me this week. It turned out that the HotSeat Billet Head was defective. I bought it off of "Scramblered" (remember him?) along with a few other "not-fitting" pieces. Last time I buy stuff used! The head was leaking coolant inside and the squish was all out of wack. Also the carb was sitting too tightly on the rubber block and it was causing it to foam up the fuel. I sure hope Mike (at HPD) gets her to work right...

 

Thanks for the reply; Highoutput. There was a review in one of the atv magazines about the Fitch catalyst. They saw no gains.

Polaris400sport;
We have no rev limiter. Our clutching and timing keeps the motor within safe rpm's. A 400EX has valves that can float at high rpm's. (Not a good thing!)

 

Macgiver, I'll cut your drive in half, come to Minnesota, and we'll go for a ride.

KT HPDHPDHPDHPDHPDHPDHPDHPDHPDHPDHPDHPD....you are getting sleepy....want speed call HPD 763-389-3336

 

have any of you guys ever tried HPDs aftermarket chassi ( i think it was hpd) if you have or have heard about it can you tell me about it. im interested in possably trying to build a polaris quad into a motocrosser. Thanks

 

Mudman, the HPD chassis kicks butt. The only drawback is the Est. $12000 price. It's a full race, harescramble, MX racer that screams. I've been trying to talk them into selling me a rolling chassis ( w/o motor) but they have their rules. The next best thing is to purchase their motor mods, lighten, widen, and stretch your quad. All depends what you're looking for.

KT

 

Does HPD have a website with a little bit of info on it? are the dimensions of it comparable to an r chassis? thanks again

 

Any machine will rev faster if any of the rotating mass is reduced. Especially in the area of wheels, tires axel sprocket etc.

If you put a jack under your rearend, and goose teh throtle with and without the wheels you'll see a big diference.

You probably have a steel sprocket that can be removed. If you have a sproket guard that rotates, yank it and replace it with a fixed skid plate. If teh wheels are steel or the tires are oversized, go with aluminum and smaller tires.

These are things you can do on your own, items around the engine require a more specialized touch, but they work too.

When racing we'd try to lighten everything that rotated. Sometimes we'd go to far and something would come apart. Be Careful.

Good luck

 

Xplor,

I really hope they get it all figured out. The engine on my xplorer hasn't given any problems, but it still worries me when anyone with the polaris 400 has major problems, whether modified or not. Good luck, and keep us posted. Might just reply to your original thread to complete it once all is fixed.

 

Racer X --

Good post. Rotating mass is seldom mentioned. Lots of small stuff that all adds up.

Another thing seldom mentioned is the cluthing system. Since it is the major load on the engine, there are things you can do to get the system to rev out quicker and sooner. If you are not at 6,500 or so at about 25 ft. out on launch, you are not getting it done. You do need to make sure the engine is up to snuff. Note that some of the larger carbs actually inhibit it getting to rev out sooner. The more atomized the fuel is entering the engine, the better cumbustion efficiency and thus throttle response is improved.

Some of the clutching techniques can also help this tremendously even though it is seldom mentioned. I've always wanted to pull the heaviest flyweight I could until it starts to affect the engine rpm, by pulling it down on launch. The next goal is to shiftout and get into high range as fast as you can. By super tuning the clutching system to eliminate inefficiency is about the best you can do on your pvt equipped quad. Weight specific clutch tuning is an absolute must if you want to get from point A to B quicker than the next guy.

The clutching components that are put out today by virtually all of the aftermarket speed merchants are general middle-of-the-road setups that will work fairly well for most. That is, unless you might weight 240 or maybe 150 lbs. Then the systems are out of whack for your body weight and will need further tuning to get it back in line.

I've seen clutching setups actually slow down the acceleration on certain setups, even though they feel like it launches harder, it may not rev out quicker.