I have a little too much time on my hands today, heh. I was going through a data log where I did a WOT run. It "appears" the car goes really lean after 5000 rpm. Can I really depend on the O2 to be that accurate? I know you need a wideband to get an accurate AFR (It's on the shopping list). The car will pull to 6k hard with no hiccups.

 

i use a conversion chart to get a rough idea... seems to be fairly accurate as well, so long as the O2 temp is held fairly constant. it's easier to have TP do the math on the fly, but this may help.

 

I am uncertain if MAF calc PE same as SD? But my time on dyno I found that my underlying (BLM) tune without use of WB came to be 12.0/1 on dyno commanded to 12.5/1 for PE. So I was pleased with that. That being said if your underlying tune and fueling is up to snuff you will be OK at WOT. So I presume my BLM was on rich side (removing) fuel so it used that BLM (123?) to do calc placing me rich on their WB.

 

while trusting a NBO2 to be accurate enough to fine tune WOT AFR may be rather questionable, it seems pretty clear cut that you're going lean in this one.

 

Thanks for the replies guys. I don't know if it's in the tune, or my fuel pump can't feed the engine fast enough at those rpms. I just threw a Walbro GSS340M 255L/Hr Fuel Pump in since the rear was out of the car. I'll datalog it and determine if it's still going lean.