Hey everyone going to be starting a new project here which was inspired by this snappy little death on 4 wheels machine:YouTube - SKi-Doo Motor Acceleration!

Anyway I have a powerplant lined up (2003 ProX VES 700 twin, 2 stroke, in the 120hp range, and about 140ish piped and a few other things which i'll be doing) and I have a couple different scrammy's on the list to check out, going to be probably picking up a lates 90's 400.

Anyway I have a few questions and i'm hoping you guys and gals can lend a hand here.

First is the suspension, seeing in how my main objectived for my project are dunes, mud drags, high speed field runs I'm curious about shock/strut upgrades and possibly going with a longer swing arm and possibly wider track width, the must are better shocks for sure. I've done some gogglin but haven't anything other than a few references that turned into dead ends, hoping for some help here.

Next is with the 4wd. What i'm curious about is the front to rear bias in the gearing (for future tire selections, planning on paddles and some good trail mudders), how far off is the gearing front the back? Also I want to look into making this 4wd all the time (yes i know its not the most pratical, but if i get one of those "watch this" moments and engage 4wd while tires are spinning i want to avoid carnage), any ideas on this, as i'm not the most knowledgable when it comes down to the workings of the polaris 4wd on demand system, but thats because i've never had one apart.


Lastly are the pipes for the sled powerplant. The motor i've arranged to pickup is coming with everything but the exhaust. Now building exhaust is no biggie, as i've built lots (i do comp mud drags & bogs with a early 80's ford 1 ton and have built the last couple pairs of zoomies for it), but I'm unsure of the 2 stroke. Does anyone know if i can run straight pipe and a regular style mufflers, or do two strokes require someting special in order to operate properly, and if so what exactly do they need?

And for those wondering the motor swap is fairly easy, with the biggest thing is getting the clutches lined up straight, building motor mounts and fabbing the exaust. thanks for any help.

 

Sounds good man!

 

two strokes have to have two stroke exhaust or they will never run right, that is how you change where you want your power, they have pipes for low end power or top speed power, it all comes down to how your air flows is how your motor will run

 

welcome to the forum. w/ good clutching and proper pipes as mentioned it should fly for sure.

 

I can only tell you about the AWD, you cant make a Polaris full time 4wd,because its a AWD. when its 4wd engages its all 4 wheels ,it would be unsteerable like having full time diff lock, because it has no front limed slip diff where only one front wheel gets power at a time.

The front Hilliary (front diff) or two Hilliary's (front hubs) are electro magnetically engaged and disengaged if the rear wheels slip about 1/8th of a turn and automatically disengage onces rear traction returns. This all happens so fast and smooth you do not even notices it.

All you have to do is leave it in AWD and you will never have the sudden awd engagement,plus the Scrambler uses the tougher two hub Hilliary that does not have the exploding roller cage issue of the new single front diff Hillary has.

 

Two stroke snowmobile motors need specific two stroke exhaust. If you have to tweak on it a little to make it fit you might lose some hp, but you are going to have plenty of horsepwer to play with. I personally would start with a aftermarket exhaust and try fitting it. The size, shape, and length of the exhaust greatly effects performance on the snowmobiles. SLP (Starting Line Products) is a good pipe manufacturer maybe check them out. www.startinglineproducts.com

 

I seen that 700 Scrambler before,heres a Video that shows the motor and pipe, looks like he had to do some pipe welding and remove the gas tank. YouTube - SKi-Doo Motor OVERVIEW

He is using a Polaris XC700 twin 2 stroke, I had that snowmobile, its 120hp stock, that must be on of the quickest ATVs out there .LOL

My XC sled would drink its 11 gal tank fast enough,I wonder how fast he goes through the 3 or 4 gal tank he made on the back?

 

So on the awd, it engages down at the wheels and not back at the tranny or diff correct (thats what i'm getting from this)? if thats the case then its better than i thought, also the lack of turning when fully locked up is of no concern to me and is something i'm very used to in my mud racing i do.

So it seems i'll have to use a pipe of some sorts, now before i go and get a hold of slp (had them in the back of my mind when starting this project), does anyone know if the pipe has to be close to the motor, or can i have back towards the rear of the quad, like how they are setup from the factory? I'd like to have it as far back as possible to avoid having to much heat down low and right by all the fluids, also i'd like to keep the area free for other things.

A larger fuel tank is a must as i do plan on taking longer trips with it, and i have a little trick up my sleeve to do this and keep everything out of sight, plus its another reason why i would like to try and keep the pipe out back.

Now onto some suspension upgrades and what you guys and gals think of the following. because of the 120+hp this thing will be pushing as i said above i want to keep it stable and on the ground, so after some searching i found someone who makes both wider a-arms (+3 per side) and a longer swing arm (up to +8). I figure i will go with the +8 swing arm, then for the front I figure I will build my own a-arms, as the a-arms on the scrammy's are really simple, probably go with a +3, but i think i will go with a +4 wider a-arm per side (basically remove the tubes from between the bushing tubethat mounts to the frame or whatever its called and the lower balljoint, then build it 4" longer with some extra bracing while keeping the angles right, then up top stretch the upper shock mount out 4" to keep the shock angles correct., then for the axles remove the center shaft-say 2" in from each joint-then sleeve it with some high strength tubing with an id that fits tightly over the factory shaft, ensureing the sleeve makes contact with the yokes on the joint, then weld it all up.

Anyway see any issues with this? It should make it pretty fun to ride, and should be wicked stable, may be a bit of a bugger in tight spots, but thats something i can live with, and it'll be mostly a dune runner/mudder/high speed vs. the tight trails.

For front shocks bout the only ones i came across were the works' units and the cost is good and they are a longer travel, so unless someone knows of another brand thats better i'm gonna go with those, then for a rear shock, anyone have any recomendations, something better than factory but won't break the bank (i'd like to keep it to 300-350 bucks, i'm trying to keep the whole project under 4500 bucks and so far so good, just the rear shock is the only thing that may toss this over that)?

Thanks for all the help so far, just a few weeks away from getting started on this.

 

i would imagine geting a 800 twin sportsman,would give you more room

 

The Scrambler will have its Front AWD engagement at each front hubs, heres a link of its internal workings ATV Time :: View topic - Polaris Demand Drive Hub Q&A Picture Guide to Service I would leave that set up alone,you will always have AWD but free wheeling when just putting around with easy steering even with AWD button is "ON". No suprise sudden high wheel spin speed engagement , same as the guy's XC700 on the Video.

The Scrambler McPherson struts not shocks on the front, most people use wheel spacers to widen its front stance but its only adds a 1/2" on each side at most. Its only suspension upgrade available is stiffer Heavy duty springs.

The bottom of the strut houses the wheel bearing and AWD Parts ,if you change its angle you change the 6 O'Clock /12 O'Clock angle of the wheel.