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[HD Street Performance]

There are many that will bolt in but what is almost excessive (compression) for the stock cam is paltry for most of the entry level players. The heads can support up to ~115hp without any port work if the compression is raised.
Want 120+ then get a 250° + 600 lift cam and rock and roll at 10.5/1 with a new TB.
Why dabble with a short cam and head work that will support in excess of what the motor can use?
The stock heads flow close to 300cfm right out of the box

[BostonboyDH]

  Here is mine, Hillside heads & blended throttle body, X pipe with V&H mufflers  I'm waiting on a D&D now the current exhaust is holding it back some!       David

[HD Street Performance]

I am sure based on the shape of the curves this is a good runner but if you are looking to compare numbers to other similar builds the defacto standard on these forums are results from a Dynojet 250I dyno with the latest Winpep 7 software displayed with "forced scaling" so that torque and horsepower cross at 5,250 rpm and an SAE correction factor applied. That does not appear to be the case here.

Once again not discrediting the builder or tuner just saying to compare with the majority of builds that are posted on these websites the data needs to be in a consistent format. The builder doesn't need to get his tail in a knot either about it, I know and have seen what this combination does when fully developed and sampled as I mentioned. That said comparing results on various dynos even with all the factors being equal is not an exact science but closer to the same.

[porthole]

displayed with "forced scaling" so that torque and horsepower cross at 5,250 rpm and an SAE correction factor applied.

Can you expound a little on this?

[BostonboyDH]

 I am aware that this is done on a Dynostar dyno and the others have been on the Dynojet 250I, and the TQ & HP cross at 5200 on the 250I charts. The tuner also has a 250I set up as a mobil dyno. The Dynostar is in his newly constructed tuning room at his shop. As to why the Dynostar chart  HP & TQ crosses at 4500 rpm I don't know? I do however profess to not being nearly as knowalegable as most on this forum, however I have spent many hours reading the posts regarding performance mods on the 110 motor in this and only this forum, as well as phone conversations with many builders! While my bike was being tuned the tuner said he was seeing reversion possibly from the exhaust system, I sent Scott at Hillside a copy of the dyno chart, then spoke with him on the phone and he recommended that the performance was suffering do to the exhaust system, so the D&D is on the way! My previous tune was done by the same tuner on his mobil 250I, 89.50 HP  107.82 TQ,

[Para Bellum]

Can you expound a little on this?

As to why the Dynostar chart  HP & TQ crosses at 4500 rpm I don't know?

What DeweysHeads is referring to in "forced scaling" is simply that HP & TQ numbers are at the same height on the graph.  This one is not; for example, 100 HP on the left side is NOT the same height as 100 TQ on the right.  If we look at most (all?) of the DynoJet dyno graphs on this site, you'll see equal numbers for HP & TQ at the same height--and the HP & TQ lines will cross at 5250 RPM.  This scaling has become the typical way to do it.

The SAE correction factor accounts for temperature, humidity, and barometric pressure, all of which affect the engine performance.  Using SAE c.f. makes it more accurate when comparing dyno results from dynos in different places and at different times.