Just got back from the dealer tuner and I'm not sure how to feel.
The original tune on my newly rebuilt motor last fall made 116.55 HP and 122.60 TQ peaking around 4K rpm. The new tune on a 1K motor made 124.43 HP and 123.75 TQ.
While the latest HP/TQ curves are not horrible, the power has definitely moved towards the right. The tuner thinks he could probably bring the HP/TQ up in 2.6K to 4K rpm range however feels that the dyno time required probably doesn't merit spending the additional money (felt it would only produce a better chart and wouldn't really be noticeable in the seat).
With the new tune, I can't really notice anything different in my butt dyno between 2 and 4K but can feel the difference above 4K (keeps pulling towards red line instead of dropping off).
I've also noticed three hesitant/flat spots between 1500 and 2100 rpm and the idle is a little rough once it's warmed up (Tach bounces about 100 rpm - seems like its misfiring at idle). EITMS is off and I'm 95% sure that there aren't any intake leaks (I did a cursory check with propane).
The duty cycle of the 4.3 injectors installed during my original tune were maxed out so larger injectors were definitely in order. However, I am now considering re-installing my old 50mm throttle body with my new 5.3 injectors.
The tuner also still had to increase the cubes to 140 and reduce the injector size from 5.3 to 5.17 in the SESPT to not be maxed out in the VE table cells (Still have a few cells at 127). The tuner said that he was essentially doing this to fool the system into adding more fuel. The only data capture that I was able to look at maxed out at 4500 rpm, 50% throttle and the injectors at this point were at 12.45ms.
In my original tune, the tuner had to set the cube to 145 and decrease the injectors from 4.35 to 4.3.
I also had to replace the lifters as one of the S&S with limiters wasn't staying pumped up and would start banging at idle and go quite if you increased the rpm. Went with Fueling HP+ lifters this time. The dealer replaced the S&S under warranty since they built the motor 6 months ago and it hasn't been ridden much since.
The tuner told me to ride it some more, note the throttle position and rpms where the hesitant/flat spots are and then bring it back and he'd re-tune those areas and address the rough idle.
Original Tune Build:- T-MAN CVO Street Performer Kit - Includes:
- CVO Street Performer Heads (2.130 intake and 1.630 exhaust valves)
- T-Man 555 Cams (same grind as T-MAN 625 but lower lift
- Forged Wisco 10.5:1 Pistons
- Cometic .040 Head Gaskets
- Final Static Compression Ratio set to 10.7:1
- Darkhorse Crank with Timken
- SE Ventilator Air Cleaner
- Stock 50 MM Throttle Body
- Stock 4.35 injectors
- Fullsac C X-Pipe with 2" cores (No Packing)
-009SAM002-01 SEPST Base Map
New Tune Changes- SE 58MM Throttle Body
- SE 5.3 Injectors
- Fullsac D X-Pipe with 2" cores (With packing and Fullsac screens)
- 009CAF002-01 SEPST Base Map
I'd like to smooth out the low rpm hesitant/flat spots that I've found and fix the rough idle. I'd also like to have the TQ that I lost between 2600 and 4000 back while not loosing what I gained on the high-end.
So what are the thoughts of the tuning experts here?
1. Is it possible that I could re-gain some of the lost TQ/HP in the 2.6 to 4K range with additional tuning in this area?
2. Any hints or suggestions regarding my rough idle? I'm willing to make some map changes and reload to try them.
3. What are your opinions on re-installing the 50mm TB but with 5.3 injectors? If I do this, can I just up the injector size in my original tune that had the 50mm TB and 4.35 injectors and run the bike with that or would it need to go back to the dyno?
4. I've also noticed that there is sometimes a significant difference in the values between the front and rear VE tables. Shouldn't these be close on a new build? I'd think that both cylinders would fill about the same at a given rpm and MAP (they're mechanically the same). Can anyone explain what the general cause for these difference are?
I've attached a pic of my dyno chart from WinPEP with both tunes overlaid and pics of new tune VE and AFR tables.