BLMs say rich, but WBO2 and NBO2 and surging all say lean - what gives?

**SkinnyG** · 07-16-2018

8063 ECU, $4D

350, ported 882 heads, 256/262 cam, Holley TBI, GM Injector pod, 18psi, headers, all in a Pontiac Firefly (CDN market Chevy Sprint)

EGR deleted and disabled

TCC disabled (TH350)

AIR disabled

DFCO currectly disabled

Can anyone see anything in my settings that I'm missing?

**dave w** · 07-17-2018

I do not have experience tuning $4D using a WBO2.

I've tuned several $OD, $OE, $31, & $E6 vehicles using a WBO2. It's not uncommon to see WBO2 averages and BLM average contradict each other. I favor the WBO2 data vs. the BLM data.

I like that $OD, $OE, $31, & $E6 vehicles have near idle and off idle tables, it's like getting the best of both worlds, near idle table for a smooth idle and off idle tables for good drivability and performance.

It might be a good plan to upgrade from $4D to one of the following; $OD, or $OE, or $31, or $E6?

dave w

**SkinnyG** · 07-18-2018

Would the quick-and-dirty-button just be map it according to the WBO2, and tighten the BLM range so it doesn't pull too much fuel out?

I had a thought that maybe high IAT might want to take fuel out, but still - wouldn't still try to hit 14.7? Intake air is a tick warm, 45°C recently. Open filter because there is no room under the hood of this car.

**dave w** · 07-18-2018

Maybe Open Loop Only, "tuned" by WBO2 would be the quick-and-dirty-button?

Usually setting minimum temperature for closed loop to 151 Celsius will keep the ECM in open loop.

dave w