Maybe this is in the wrong section but I figured it might help a lot of people in the engine section see the importance of this tuning tool.

This was shot on the chassis dyno last year. The red LED that is on is my fan and the one that comes on during the run is when my meth starts to spray. As you can see & hear we are slowly accelerating in 1st and 2nd gear until we reach 3rd. The wide band is showing as very lean but the vac/boost gauge is still showing a vac situation. I've since corrected this situation. What is happening is the bonnet is seeing a slight amount of boost and it is confusing the powervalve (not opening) and not allowing it to richen the part throttle. I corrected this by boost referencing the powervalve (PV). This entailed drilling the main body of the carb and installing a nipple so I could pressurize the hollow area behind the PV. I also had to mod the PV so a spring would keep it closed rather than vacuum. Now when the bonnet sees boost it pressurizes the area behind the PV and opens the circuit. This is called a BRPV = Boost Referenced Powervalve.

The car drove fine and there was only a little surge at part throttle. Nothing to indicate how lean it really was.

We hit the throttle at 2500rpm and the run ends around 4500rpm. Under boost it is still a little rich at high 10s/low11s. Ideally you would want it around 11.5:1 for a boosted application.

Oil pressure looked good as well as the engine temp. The engine picked up 10*f for the run
259rwhp/345rwtq

http://www.youtube.com/watch?v=KjBHib4I3Vw

what brand is the a/f reader?

Surge is still lean issues. You need a A/F meter that responds really QUICKLY with clear status like a gauge for very short transitions.

I use 20 LED in a arc made by autometer for gauge and my DIY WB kit by JAWS.

Cheers, Wizard

That one is an AEM. Innovative is popular because it records and has some other functions as well.

Maybe I was unclear...the surge was before I did the BRPV. Now it is fine.