Timing Curve Guidelines

[1997bagger]

Reading until my eyes crossed, I understand that dyno's are the only way to set timing by HP readings. Is there a rule of thumb for timing basics? engine builds determine too many variations of timing adjustments and I'm aware of that.
I get a impression that tuners don't give out the art of this subject and fully understand but if someone just happens to leak some knowledge in a mumble, I'm listening 

[whittlebeast]

If you have the ability to to data log your SERT, It is fairly easy to compare the rate of acceleration using the free MegaLogViewer software.  Just use 2ed gear and the same section of real flat road on every test.  You look at the RPM/sec field.  It there is no improvment by going up in timing then you are close.  Always remember to have the spark retard field ploted.  If any spark retard sets in, you are too abvanced or too lean.

You really cant do this very well on a dyno as you can't duplicate the engine cooling and intake air temps.  In a Harley bagger this is huge.  I am seeing HUGE IATs on a warm day when using most all of the common air cleaners.

Have fun tuning

AW

[Steve Cole]

You need to understand a few basic things when looking at the timing. More is not always better which most believe. The simple truth is that there is some trial and error in finding the best timing curve you can. What you have for equipment plays a major role in what you can and cannot do. If I assume from your name you have a 1997 it could be EFI or a Carb. In either case your going to need something that will allow you to be able to change the timing to figure out what your combination needs.

[1997bagger]

Thanks Steve, appreciate opening up your experiance with this topic. Whittlebeast, I always read your posts and at ahh sometimes with your advanced knowledge of EFI but I use the simplicity of the PC3, your Sert language is a little foreign to me but I take it in and will someday have value. I understand spark retard is the knock sensor but I don't have one.

I have 97 EFI 89" 10.2-1, PC3 and WEGO3 afr system with O2 sensor, The problem is I have most timing cells at -10 and two AFR cells (individual cyl tuning) need more fuel but are maxed out. I have slight detonation in the maxed out area in 5th gear due to AFR is at 14.0 instead of 13.2 but later in the TP and WOT is a fine line from being flat power to a rattle and AFR is good, I inherited the Stage 2 flash and have read that it complicates timing settings.

I'm aware of a higher pressure fuel regulator to solve the maxed cells but I will have to retune all over again but changing timing correctly is vague to me, that is way I looked for professional help.

Would purchasing a SERT and converting my WEGO3 (PC3 table) readings to VE's be a better system for the future? I've read the Sert has the ability to allow more fuel than a PC3 and I won't need to mess with my fuel system and I can learn Whittlebeast language 

Once again, I appreciate 2 tuning veterans taking time to show guidance because tuning is very complicated.