I recently found a nice programm, by some reasons as an older version only, which is quite interesting to play around with. It's called Engine Analyzer Pro V3.3 and as one of the first results it came up with the below shown spark advance curve (WOT), which is quite different to the OEM one (going up well over 40°)

http://img16.imageshack.us/img16/6639/sparkadvance.th.jpg

What do you think of it? Any similar experiments out there with sharable results?

Hubert

Hubert, could you tell us more about the program.
In addition to mapping the spark advance, does it offer recommendations?

Joe

It came up with this just from blueprint data? Cool. Try using that map and report the results!

sign216 wrote on 06/04/12 at 08:35:09:

... does it offer recommendations?...

Not really. But you can switch the head from Hemi to Hemi Dual Plugged for instance and see how the thermal efficiency goes up, what that means for the achieveable torque and how much the spark advance could be reduced in this case. Things like that. It gives a nice overview how things work inside an engine I'd say.
The shown curve corresponds well with where my engine is pinging on hot days, by the way.
hubert

No one tried it yet?

The graph is a little deceptive as it looks like it has a big dip in it but in reality it is only 2 degrees

Does the program not do anything below 3000?

It goes below 3000, and above 8000 as well.
Shown below is the output based on standard V11 cams:

http://img651.imageshack.us/img651/7223/v11standard.th.jpg

Next pic is the same virtual engine but a different camshaft:

http://img528.imageshack.us/img528/7216/vergleichseriehwcam.th.jpg

It shows volumetric efficiencies

http://img706.imageshack.us/img706/3118/volefficency.th.jpg

corresponding 'knock numbers'

http://img854.imageshack.us/img854/926/knockindex.th.jpg

and, as mentioned before, resulting (estimated) advance curves

http://img715.imageshack.us/img715/5576/spadvance2.th.jpg

instead of making your own you could go (and I probably would next time) for a Norris 620x3 (sold by MegaCycle Cams) as well:

http://img24.imageshack.us/img24/5035/norrisx3vshwcam.th.jpg

Regardless what absolute numbers this proggy delivers the tendencies it comes up with are quite real. The very good torque but weak high end power is exactly what I noticed. And the V11 standard curves also represent very well the numbers found in any other publication.
Another fine thing is to switch from 'full exhaust' to 'open pipes', btw.

Hubert