OK, Hopefully you have read the Article on why clutching RPM changes do NOT really tell you if your latest and greatest addition gave any REAL performance gain.. If, you have not read it, please, take the 5 minutes to do so because it will allow this article to make more sense.

OK, here we go… So, we know that you can NOT rely on your clutching to tell you whether you added performance with your new addition. So, how does one determine if the hard earned money you spent was worthwhile? SIMPLE.. you determine this by testing it in the REAL WORLD.. ON THE SNOW.. where it really counts.. Not on a dyno but on the snow!

Let’s back up a bit with a bit of “common sense” reasoning and theory.

1)ANY internal combustion engine MUST be loaded in order to produce max power. Free-wheeling or unloaded engines simply do not produce. Remove the belt from your engine, rev the engine, and your ears will tell you that there is no real power being produced without the load applied to the crankshaft.  ALL dyno tests are done using a “LOAD” to load the engine. Otherwise, the max torque outputted could not be measured.

OK.. Same applies in the real world (on the snow). You must place a load on the engine to make the engine produce. The heavier the load, the more internal heat is produced and that heat is converted to power via the engine.

Example: Take 2 new trucks.. 1 gas truck at 400HP and 1 diesel at 400HP, get on I-70 in Nebraska and line them up.. What happens? Well.. they run very even.

OK, same 2 trucks, now put 8,000 lbs of trailer behind each. Same I-70 in Nebraska.. Line them up.. What happens now? Well.. The diesel runs much faster than the gasoline truck. How can this be? We just ran them without the 8,000 lb load and they were equal.  Answer: LOAD.. Once loaded, the truck that can MAINTAIN power performs better than the one that is struggling to maintain the power.

NOW, take it one step further, same 2 trucks, same 8,000lb load but now take them to 8000ft elevation on a 5% uphill windy grade that goes on for 10 miles. Line them up.. What happens?? Well, the diesel truck is at the top eating lunch before the gasoline truck crests the top with an overheated transmission and near over-heated engine. Again… LOAD changes everything!

So, 3 different scenarios with NOTHING changing but the load applied to the engine/vehicle and you have 3 VERY different outcomes in terms of “how bad” one outperforms the other. NOTE: the HP/TORQUE of either engine never changed.  Just the manner in which it was tasked changed.

Next time you hear about the amount of "lengths" one gained with ANY product. PLEASE ask them how it did under a heavy load.

SAME applies with snowmobile performance. UNTIL you place the sled in a heavy load situation, you will not always be able to determine if the performance is better or worse than the stocker.

EXAMPLE:  2 identical snowmobiles other than one has some power enhancement modifications (ie. pipe, head, pistons etc.) Line ‘em up on a road. What happens?? The mod one may or may not run faster in a short distance. It all depends on how the sled is clutched and if the current clutching calibration allows the sled to benefit from the added power. In other words, it may be hard to determine if there is a power difference between the 2 sleds.

OK, take them to a meadow with 2 ft of powder.. Line ‘em up. What happens?? Probably about the same as what happened on the road comparison with the mod sled probably running a tad faster. Still, it MAY be difficult to differentiate between the 2 in terms of power.

OK, take them to them to a BIG hill with 3ft of fresh powder and about 1000 ft of hill to pull. THIS is where you will see whether you actually added some power or not! These sleds have the same tracks and chassis. They are identical in every way except for the engine changes. No need to line ‘em up.. Just try and get to the top of the hill that is in front of you.

NOW, you can see the results of the engine modifications.

IF there is truly power added, there will be a NOTICEABLE difference in how high up the hill one sled is able to achieve vs. the other. Absolutely, NO QUESTION, providing both are running at proper RPM and all clutching is healthy, the sled with the more power WILL be higher on the hill… EVERYTIME! 

The higher powered sled will always be able to out climb the lower powered sled. While it may not be able to out “race” it on the flats or in the meadows, once the LOAD is placed on the engine, the added power will be revealed.

OK, we also hear about the “midrange” power enhancement that may accompany a performance product. Midrange power is always welcome and can make your sled more enjoyable to ride due to more “snappy” throttle response. Again, great stuff and welcome, for sure. BUT… midrange power is power that is achieved at BELOW peak operating rpm. So, if your peak power operating RPM is 8200, midrange power would be in that 6500-7500 RPM range. You know.. the “crusin’” RPM. So, if your riding style favors a lot of “crusin” then this type of power enhancement would be a great thing to have. BUT.. Please do not mistake ANY gain in midrange RPM power to translate to PEAK RPM power gains. These are VERY different. Gains realized at midrange RPM are not necessarily realized at PEAK RPM.

Ask yourself, when you are racing across the field or climbing that big chute, are you running at PEAK RPM or MIDRANGE RPM?  Last time I checked the tach, I was not climbing ANYTHING in the midrange RPM. If I was, then the climb did not require much power.

So, not to worry, most products that give your some good PEAK RPM power gains also give you midrange RPM gains as well. The reverse is not always true. You can have products that boost midrange RPM yet give little to no power at the PEAK RPM.

So, be sure that you know what RPM the product you are considering dropping your hard earned $$ on benefits the RPM range that favors your riding style


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