David94TA

I know the way to tune for WOT is put it on the dyno and do a 4th gear pull. But can you get an idea of where your tune is by doing a 3rd gear pull on the street or strip? Or is it totally different?

Injuneer

They do chassis dyno pulls in the tranny's 1:1 gear. Engine dyno pulls are done with no tranny at all. The engine dyno controls acceleration at a fixed RPM/second. For my engine, they use 300 RPM/second on the engine dyno.

What device are you using to evaluate the tune on the street? Are you data logging? Or is this just SOTP? Do it in the highest numerical gear that wont endanger you with excessive speed.

David94TA

I use an Innovate LM2 wideband O2 sensor. The unit has additional channels so I have it set up to log throttle position and PSI (use a separate 2 bar MAP sensor) in addition to rpm and A/F.
I also use the datalogging feature of LT1 Edit. I guess my question is will a third gear pull give me fairly accurate information as doing a 4th gear pull since everything is happening so much faster? Just thought I would try to get it close before going to the dyno.

Injuneer

Should be OK. Bottom line is you will be seeing that gear while racing, so it's a measure of how well the engine will perform.

Is the wide-band sensor in one bank, or both combined? If only one side, can you switch it to check both banks?

David94TA

Both combined. Have the sensor located downstream past the Y pipe.

Thanks