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[IRNEngineer]

Here are the results of my Dyno test from a couple days ago. Weather has prevented any riding since the test, so I can't comment on the actual physical impact of the tuning. Based on the chart, what do you think? How does this chart compare to the results you all have seen?

2016 FLHXSE with V&H Power Duals + 4" Rinehart = 94hp and 112 ft-lbs torque.

[IRNEngineer]

Forgot to add - SE Pro Tuner.

[East Coast]

Your right in the ballpark of where it should be. 

[IRNEngineer]

Thanks,  East Coast. Good to know. The technician came with good recommendations, but I value the expertise of the CVO members here.

[Royalroadie]

I have the same exhaust with a TTS 94hp 116tq.  Your right where you should be.

[Mr D]

Here are the results of my Dyno test from a couple days ago. Weather has prevented any riding since the test, so I can't comment on the actual physical impact of the tuning. Based on the chart, what do you think? How does this chart compare to the results you all have seen?

2016 FLHXSE with V&H Power Duals + 4" Rinehart = 94hp and 112 ft-lbs torque.

Instead of a STD can you post a SAE graph ?

[IRNEngineer]

MR D - The attached STD graph was all I was given by the technician. I don't have an SAE graph to post.

[Para Bellum]

MR D - The attached STD graph was all I was given by the technician. I don't have an SAE graph to post.

Both STD (standard) and SAE (Society of Automotive Engineers) are correction factors (see more on this below). On this forum, the "normal" way of reporting HP and TQ is in SAE form, which is why people ask.  Any comparisons have to be done using the same correction factor, or the comparison isn't valid.  While I haven't done the math myself to determine how much higher STD is than SAE, reliable sources put it at 2.6% higher.  So, the SAE HP value would be 94.23/1.026 = 91.84, and torque is 112.28/1.026 = 109.43

A lot of techs only give you the graph/numbers in STD (standard) instead of SAE (Society of Automotive Engineers) format because the STD numbers are higher.  This makes the tech (the tuning and/or the build he did) look better.  You can get the SAE numbers from the tech just by asking for a printout in SAE form. 

All engines make more power at cooler temperatures and higher air (aka barometric) pressure.  So the engine's output changes as the air temp, air pressure, and humidity change.  To make the dyno's numbers more accurately show how the engine is performing, the dyno has software that takes the actual output under the actual conditions (known as "uncorrected"), and calculates what the engine would make at a constant temp, press, and humidity.

The reason STD gives better numbers than SAE is that STD uses a higher barometric pressure (29.92 inches of Hg vs 29.234) and a cooler temperature (60*F vs 77*F).

Now, on your dyno graph, the CF (correction factor) is shown as CF STD 1.04...meaning that the dyno software took the actual output at that day's conditions and multiplied it by 1.04 (a 4% increase) to adjust it to Standard Conditions.  The uncorrected values are HP 90.6 and TQ 107.96

One more thing:  Even with correction factors, different dynos will show different numbers for the same bike, so it's hard to make comparisons.  That said, although the shape of the Air:Fuel Ratio (AFR) curves are good, they are on the lean side for a dyno run.  You might pick up some power if the tune was made richer.

[IRNEngineer]

PARA - thanks for the detailed response.  Very helpful. I'm guessing tuning and riding in Missouri @ 90+F and high humidity doesn't produce the best power. I came off a stock 96, so the 110 feels great. My main concern was just to know if the tune looked alright.  I've read several comments warning about bad dynos, but this shop has a good reputation. Thanks again.

[Mr D]

A lot of techs only give you the graph/numbers in STD (standard) instead of SAE (Society of Automotive Engineers) format because the STD numbers are higher.  This makes the tech (the tuning and/or the build he did) look better.

Very good explanation 

SAE should allow for more accurately presented data. Keeps the level of play more fair