2010 Roadster Dyno/Tune ECU Issue

[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

 

[Power-Tripp]

Alex,
As per the email I sent, this looks like detonation in 5th gear.

Looking at the dyno charts, it seems to start just below peak torque rpm and continue to over 6000 rpm - in varying amounts.

Lambda/AFR sensors read residual oxygen in the exhaust. When detonation occurs, residual O2 changes, and the sensor sees this as a change in mixture ratio - it isn't.

This is one of the limitations of Lambda/AFR/O2 sensors and meters that the dyno operator should be aware of.

Pull a few degrees of ignition advance from 3500 rpm and higher, and add some fuel to cylinder #3. Do this at all points (rpm and TPS) where this problem occurs.

 

[Bratman]

Thanks Wayne, really appreciate your help. This makes total sense. After the changes, both timing and fuel, I plan to run it on the dyno next week. I should be able to do this and post confirmation by Firday, Aug. 20.

The strange thing is that the detonation is essentially under stock conditions, i.e. stock tune for TORS and just the K&N underseat replacement filter. I can't understand why Triumph would set it up on the verge of detonation (?). Maybe bad gas, but I dynod twice with different gas and even different dynos, with similar results 4th vs 5th.

Thanks again for all your help.

Alex

 

[Power-Tripp]

Always happy to help an enthusiast. Post up the results - especially if I am wrong.

FWIW, Triumph's Arrow maps for the 1050 Speed Triple will ping from 2800-4800 rpm above 50% TPS when running 93 PON fuel (98 RON)... even though Triumph recommends 89 octane PON. 3-4 degrees less advance usually fixes this.

WHY would these maps be like this?

I can't answer that.

 

[Bratman]

Thanks, that explains why my 09 Speed Triple pings... Thought I was safe on premium fuel (93 US/CDN), with the Arrows 3-1 low pipe and K&N replacement filter with the corresponding Triumph tune, but I recently heard some pinging in the range you mentioned, which is why I'm looking for a better tune/map.

Other than pulling advance, do you think I should richen it up across the board, or in certain areas? I was thinking of adding 5% actoss the board at all TPS. Should I turn off the O2 sensor while I'm at it?

Lastly, I have a 17 tooth front (instead of stock 18) with stock rear - any idea what the speedo corrections should be? Thanks again.

Alex

 

[Power-Tripp]

I have some really good late model S3 maps, however, they are in TuneEdit format, not TuneECU's hex format.