Dyno numbers are absolutely relative. Not just relative to the specific conditions, relative to everywhere and anything that opens up the possibility of variance. This includes but is not limited to conditions such as density, humidity, altitude, pressure etc.., how the air is exchanged in the dyno cell, how fans cool the motor or feed the intake, the specific engine temp the engine is tested at (as there are big differences in spark timing alone on a cold motor vs hot), not to mention other variables as belt and primary chain tension, engine oil, tire pressure, the specific fuel in the tank, all of which will make a difference. That is not even taking the specific tune into consideration which is HUGE. Understanding these variables it is very easy note there can be 10% or more difference between one test to the next, this could even be on the same dyno different days. The key is to keeping everything consistent with your testing.

 

I would like to see a chart where a HPI tb(vs a stock tb) hurt torque at all and did not boost the hp by 4 -10. Not saying it does not exist, but I think it would be a rare chart.

 

We have tested many different throttle bodies over the years with many combinations, especially our 107 builds. My personal bike has had no less than half a dozen different TB's on it at different times. On throttle by wire touring models which have a stock 50mm throttle body there are not typically gains with increasing the TB size with most typical builds unless you are in the 120Hp range, on the other hand the cable bikes including the Softail & Dyna models use a 46mm TB which we generally replace it if our objectives are much over 100Hp. In the end swapping the throttle body will only add Hp/Tq is if it does not flow correctly for what a given combination requires. It all comes down to testing and knowing what works for a given setup.

 

My point was "lose torque on the bottom end" compared to a 50mm TB .... please don't confuse this with peak torque. My FM107" makes 100 ft-lbs at 2600 with the FM's polish and A/C port match on the stock 50mm. Alot of the charts posted with 107" kits and a 58mm (at least those I have seen) don't make 100 ft-lbs. until closer to 3,000. For my riding style, I want my torque as early as possible.

 

For sure most of my time has been spent looking at Dynas(ride a Fat Bob), so I can see that the 50mm stock tb on the baggers is a huge bonus compared to the 46mm I have. If I had the 50mm, I would not upgrade to a bigger/better tb like HPI either but if Carbo wants to chase a few more ponies, I still think he would pick up several with a HPI. Is it worth it? - not to me but if you got the $$, why not?

I do have a 55mm HPI waiting for me to get to work on my build!

 

definitely an awesome component, the HPI stuff is top notch. We use them quite a bit, we have the HPI 62mm unit on our 155Hp Dyna

 

Thanks for the explanation Jaime. I have to say I'm very happy with the way the bike runs, especially in the lower end. No complaints here!!!!! Already planning on another FM build for the new '14 Road King.

 

Read all the post from Page 1.

Sounds like a Solid kit and sound like it works well.
Glad to hear everybody that is happy.

 

I am considering this kit for my 14 SG.

 

In doing this 107 build. Did anybody check the Deck Height ?

Or did you just put the kit together ?