R3R Dyno Results in 4th vs. 5th

[Bratman]

I have a Roadster with TORS and underseat K&N and just got TuneECU and some dyno tuning; 131 hp/148 ft lb torque. TuneECU with 100% open secondaries everywhere, air fuel richer bottom and top and a bit richer through the middle, timing +2 degrees, 6700 rev limiter, speed limiter raised to 299 km (max). This is based on the 20355 TORS tune.

Interesting issue; when we dyno in 4th gear the air fuel line is pretty much flat at 13 right to the limiter, however, when we try it in 5th it spikes to 15 @ 5.5 - 6k rpm, then back to 13 by 6.2k rpm.

Can't figure out why 4th gear has flat air fuel but 5th gear spikes. Making changes in Tune ECU to correct for the spike seem to only affect the 4th gear air fuel but do not seem to affect the spike in 5th (?). Thought it might be misreading, but we tried a bunch of times with same results. The hp & torque were very consistent though regardless of the air fuel spike and 4th vs 5th gear.

Your help or any thoughts would be appreciated. Thanks in advance.

Cheers,

Alex

 

[fat frank]

As to your +2 degree in timing, did you do any pulls before changing the timing to see the results? I've got some advance in mine also and just curious. It was loaded in my tune so I didn't get to see if there was an improvement. On my Bonnie with 80+ RWHP, she liked 1 degree retarded.
Any gurus out here that have proven the advance is the way to go. I mean really spent some time on the dyno changing the ign timing.
Thanks in advance

 

[KingOfFleece]

Ask wayne at power-Tripp. If I remember correct he had a post about the 4/5 gear mixture.

 

[fat frank]

Just got off of the dyno and saw the same spike. And like you say, the hp and dtorque where the same.