Originally Posted by Harleypingman

Mark, viewers of dyno sheets can decide for themselves what to make of them. For some, a dynos sheet on a particular cam, SE kit, indy's headwork, etc. is THE holy grail of comparison to other cams, kits, etc.

For others, a dyno sheet is a way to confirm that the engine has been correctly assembled. Since many of the builds are repeat builds (i.e. others have assembled identical or highly simlilar builds) the WOT sheet will validate that the engine has been assembled and tuned correctly. If there is a gross deviation (e.g. the engine puts out significantly less power), that probably indicates a problem such as sumping, misaligned cams, etc. If the dyno sheet shows numbers significantly higher than virtually identical builds (say, 10% higher) from a particular tuner, the numbers may be the result of a dyno that simply reads higher hp and torque (i.e. the tuner isn't manipulating the dyno to generate higher numbers) or the tuner may be manipulating the dyno to produce higher numbers to attrace business for himself or the shop that uses him to tune their builds. In either case, looking at dyno sheets from other tuners for the same or nearly identical builds tends to identify the happy dyno.

As for your repeated question about posting dyno sheets by those who say the numbers don't mean anything, that's more an expression about the specific numbers resulting from a properly assembled engine and sharing with others that information for general comparative purposes.

Taking PhilM's 124 build as an example, Ed could have continued to advance timing and adding fuel in the WOT runs to the point of pinging in each rpm segment from 2K to 6500 rpm and backed off 3 degrees of timing when pingning was detected and had a maximum power tune. However, in July and August when it's much hotter in Dallas, that max power tune would probably ping like crazy because the air would be less dense (less oxygen), and Phil would need to take out some timing to eliminate the tune. As Ed explained, they didn't do a max power tune.

As for folks being "giddy" about PhilM's peak dyno numbers, I wouldn't characterize the comments that way. In any event, there is no denying that PhilM's build is not what we usually see on HDF from one of our own. And I don't see many 130 hp/150 tq Road Glides around. So yes, I'm impressed to see someone take a twin cam motor and produce that kind of power in a streetable touring bike that can deliver 40+ mpg.

You're having a 117" engine built for you. I hope you will do as Phil did and post pictures of how the engine was assembled, what components you used, and how the bike behaves after the engine is installed and you've gotten some miles on it.

Carl

Originally Posted by jag1886

Dyno's do seem to very one to another, here in Boise there are 2 dyno's in town, maybe 3 but anyway the local Indy says that the local Harley shops dyno reads high, he dyno's bikes that have come from the dealer and they read no ware as high as the dealers readings.
I don't know which one is right but they do vary.

Originally Posted by hog-doc

Originally Posted by Biggzed

Mark -

Plain and simple. A dyno sheet showing "uncorrected" or "actual" hp and tq numbers is always going to be questioned on forums. It's simply reality. I believe this is where this entire pissing match with Phil's thread started and why you created this thread. Without showing SAE correction, as Ed pointed out, there will continue to be questions.

Zach

Originally Posted by Mark MPDC

So what most of you are saying is that the numbers some people post on here about their builds can be false numbers no matter who the build is done by is that correct?