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I recently had a dyno tune on a 06 FLHTCUSE using the Screaming Eagle Race Tuner. I have noticed that the tuner started with the base map for the 05 SEEG 103 CVO (127HX022-B0.MT6). That bike has a different injector size. The new injectors are 3.91 gm/sec vs 4.35 gm/sec from last year. In the ECM tuning constant table of the SERT there is a location to change the injector size. That constant was not changed to match the 06 injector of 3.91 gm/sec. Will that have an effect on the performanance or caused a lean condition or has he tuned around it?

:dunno:
 

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Since the ECM thinks it has the larger injector,,computed pulse widths to hit the target a/f ratios in the map will be based on that injector size....so he would have hopefully tuned elsewhere to add more fuel...Incresed VE's and lowered a/f's. Were it a closed loop system with a Wide Band 02...it would compensate by itself. You need the A/F sheet from the dyno to see where it's at.
Now I havent compared the 06 map to the 127 map for the 05 cause I dont have 4.50 version of the SERT. ASK him "why" would be the first thing to do.
We may all learn something....
 

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SYCLONE said:
Since the ECM thinks it has the larger injector,,computed pulse widths to hit the target a/f ratios in the map will be based on that injector size....so he would have hopefully tuned elsewhere to add more fuel...Incresed VE's and lowered a/f's. Were it a closed loop system with a Wide Band 02...it would compensate by itself. You need the A/F sheet from the dyno to see where it's at.
Now I havent compared the 06 map to the 127 map for the 05 cause I dont have 4.50 version of the SERT. ASK him "why" would be the first thing to do.
We may all learn something....
I agree, ask the tuner why he did that because that is not the intuitive way to tune that motor.

and my question is.....

Are the '06 injectors only different to the '05's when held wide open?

If both were side by side and we could measure output at 2mS, 3mS and 20mS and so forth.... I would suspect there may be little or no difference until measured for full output.

Just guessing though, would like to hear definitively from someone on this.

If this is the case, then the VE tables would have to be adjusted as Syclone said. Especially at 100% throttle.

By the way, I just took a peek at the 127HX022 map, pretty normal looking until you look at what they did in the spark tables. sheeeeesh! weird.

I would like to know how they derive their spark tables for these maps.
 

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The timing tables for the CVO 103's are odd because of the Hemi shaped combustion chambers with like no squish at all.
 
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