Joe,
I had the Stage II ECM download since 2002 when I went 95" inch. I went with this download for the timing changes appropriate for HD 95" / 203 cam builds. As a result, I've never experienced pinging under any load or condition when I ran the TW21G, the TW26G or in my present build. I had considered a HD ECM reflash back to the Stage I download, but after researching the differences between the HD Stage I, II ECM downloads I came to the conclusion to stay with the Stage II for the timing changes.
Some additional info I found on Stage II ECM downloads.
Mike at Team Latus: Response to question; Is an ECM download required even though a Power Commander is installed?
Chris, perhaps in an effort to give you the best possible and most correct product we may have been overly enthusiastic with respect to the cartridge re-calibration. It is our policy to STRONGLY recommend a calibration, in modified bikes utilizing Power Commanders, which brings the ECM as close as possible to the performance combination installed. The reasons for this are;
The values in the PC mapping will not be as large or as likely to hit limits. Very large values or transitions (between cells) can lead to drivability issues. As a “piggy back” device, it starts with the ECM values which it must then modify to be correct for the bike combination. The less appropriate the base ECM, the larger these modifiers must be.
Should the PC fail (rare these days), the bike would be in a rideable condition vs. putting it on a trailer. The risk being a very lean or other condition which could lead to motor damage or failure, when the PC is not actively modifying the base ECM. We wish our customers to be aware of this risk and the additional $150.00 expense is good insurance for this protection.
From a strictly technical standpoint, we feel this is the correct approach and results in a better overall tune. The base ECM offsets, tuning constants, spark tables, VE tables, warmup enrichment and other tables will be more effective with a base cal. that is closer to the combination to be tuned. There are a lot of tables in the base ECM which the PC does not address.
We recognize that Dynojet and others advise that the re-calibration is not required and that the PC is capable of tuning from a stock calibration. This is true and we would (and do) tune PC equipped bikes with stock or stg1 cals., so long as customers are advised of the above recommendation and are therefore making an informed decision. It would be remiss of us NOT to inform customers of this risk as they often rely upon us to be “the experts” and to give them what information we have that may affect their motorcycle. We stand by our reputation in this field, will continue to have these discussions with our customers thus allowing our customers to be the most informed and knowledgeable about their bikes and related decisions. This letter will be given to our staff so that, in the future, our customer conversations will be consistent. Your letter will be cc’d to our service manager, Fred King.
Regards, Mike
From GROCK of VTwin Forum
Timing is also changed from stock when doing the download. Depending on cams it can be very gentle to a little more aggressive for some of the HP maps. But none of them are really aggressive. If you are thinking of getting the flash to get the REV limiter up, then you will benefit slightly from timing change also. Although I am never a big fan of the $150 for the dealer flash, especially for the change into a mild 26 cam, going to a 95" gets a little better throttle response and high end running with the flash. You also get slightly different parameters for idle, starting, etc., as the ECU is now adjusted for a 95" and adjusts tables accordingly.
Miscellaneous forum info regarding HD ECM do
