Engine management (the need for a fuel controller or not) is primarily based on the load you create through the CVT (clutches, transmission). If you don't add load (to use the new found power) you won't use the power and won't need to add a controller.
Stock Polaris clutching does not load the mid-range very much and zips through the rpm to peak very quickly and just sits there. Some like this and call it snappy and it backshifts very well.
It's also the way a CVT is supposed to work. Peak rpm all the time but,, since sledding began, many have used loading the clutches to add to acceleration. We all know this and try to make the motor pull more. That`s when fuel injection needs some adjustment if the stock map is close.
When you talk of adding a controller to the Pro you have to separate 2013's from the previous years because Poo refined the EPA approved fuel management to IMO beyond the edge of leaness. It's the added snap many say the 13 shows. If you load a 2013 stock in the mid shift you need to add fuel or risk lean issues at less than full throttle.
At full throttle the fuel ratio is still safe enough for the long lake and tree-free hill pulls that Poo has to safeguard against. They also add to the warranty required safety margin with timing retard and added fuel at higher coolant temps.
This is why some pipe builders say you don`t need a controller. They test and tune at full throttle (SLP is different and tests for mountain use. Reason you see a lot of SLP stuff on SW. It works as a package. They also add the disclaimer that you need the "package" or risk some engine management issues.).
IMO if the pipe builder recommends no controller on a '13 Pro, they have not tested in the mountains where you are always into and out of the throttle. If your looking for a package to use in the mountains, stick with a package that is refined in the mountains.
Some pipe builders have a pipe for high altitude and one for low altitude. This tells you they care about both markets because the needs are different. But, do they primarily test at low elevation or high?
These are all important things to know when you pick your pipe builder.
So what is the point of the pipe? IMO, with todays engine packages, it is mostly bling. Or, a step towards a bigger package later. Or, a "quest" lol, to shorten track speed build up time which can be felt in your arse IF you get the clutching right and the engine management right.
We ride sleds not bikes. You only get about 50% of the added power to the track (where it finally gets to move the sled and you forward) if you get the clutching right.
Say the pipe you put on your Pro adds 5 ponies on top. You are putting about 70 ponies to the track stock (just a estimate). Now you have 72.5 if you get 100% use of it. That's a very small PERCENTAGE of gain. Will it blow the side panels off your buddy's identical stocker? Not likely.
Most of the better pipes add more to the mid than top (because the manufacturer has already done a darn good job on the stock pipe) and more important add torque. Torque moves you and more importantly, the track. If you harness that torque and midrange with your clutching you will feel the added power and it will make you grin and life will be easier on the side of a slope if that is where you live on the mountains.
An example. Say your trying to turn under a tree to go up over the next. The stock set-up may pull your track speed up to 35mph in 2 sec. during the clutching phase of your shift ( 0 to 30 mph maybe, depending on your gearing). Now harness the added 10% midrange torque that the pipe gave you and that track speed jump may get to 40mph in less than 2 sec.
That's a huge gain in that particular example. That is what the arse feels. That may be enough to make the maneuver and leave your buddy on the stocker stuck lol.
That's why I added a head (more torque yet) and pipe. Not a lot of gain overall and it won't really show on a long pull and you could get the same (to a point) by refining clutches on a stocker.
I don't care about a couple of sled lengths but 5 mph of added instant track speed is fun to feel and has saved me a couple of times when I geeked. Will it get me up and over something that a stocker won't. Not likely.
Hope that makes it easier for you to decide lol.
