I just installed my WBC. My A/F is smooth @ 11.2 during WOT in all gears but during the 1-2, 2-3 shifts it spikes to 15.0 or so. What causes it to lean out during the shift? is this normal or something I should be concerned with?
I have a 4#,Dyno tuned pred, Densos, Borla, Filter and a 2,600 stall if it helps?

 

11.2 at WOT is pretty fat IMO. If your willing to go leaner you could see some more power.

Rich

 

I completley agree!! I'm still running consistant 12.6s @ 108+ on a FATTY tune and a 4,960# raceweight! But my main concern now is why my A/F is spiking during all the shifts?

 

I'm not a tuner, however when the vehicle is at idle it generally runs real lean and then as the engine comes under load it richens up. Now I'm guessing during the shift the engine is under less load and therefore it leans out.

Also, looking at my a/F graph, the lower the RPM's Drop (during a shift) the leaner my tune is... Until it hits about 4200RPM's then it richens up.

Does this help? If not, Disregard.

 

Anyone else?

 

Mt MPH is down for 437 RWHP. I run 108 (and change) MPH and this was what originally interested me in this thread, but I guess it has turned into an A/F thread.

 

um... this is a A/F question Blown347Hatch

Rich

 

My WBC reads 11.5 on my non spray tune in 1st,2nd,3rd. 11.2 on spray in 1st and 2nd then it drops to a 10.0 in third

 

How hard was the install? I've thinking about getting a WBC. Im not sure why your A/F would spike so lean during shifts???

 

My truck does close to the same thing. I think mine spikes right before the shift. What year is your truck? Are you using a predator?

I haven't ever found out why it does it. I am no where near the hp where MAF or Fuel systems need to be upgraded. I have also been told that the A/F data in 1st and 2nd are really not that important, 3rd gear is the only gear we need to worry about.

Mike

 

It's an 03 with a dyno tuned Predator.

 

If I can install it anyone can. The only thing I paid to get done was having the 02 bung welded in the driver side pipe above the upper cat.
There is a rubber gromet under the driver side carpet about 4" in from the door sill. Thats where I ran the main harness that plugs into the 02.
The instruction that come with are pretty good. Just use comom sense and read them well and it's cake!

 

Mine is an 03 with a mail order tuned predator. This might have something to do with it. Here is a graph I did last year after exporting the data from the WBC.


This is a tune from RWTD. I had a tune from Sal and it did close to the same thing. I was on the street when I got the data so I counldn't get into 3rd. Both tuners say they only need the data from a 3rd gear pull unless 1st and 2nd are really messed up.

 

That's different then mine? Mine spikes for a split second just during the shift but it spikes anywhere from 14.0 to 16.0!!!!!

PLEASE SOMEBODY HELP

 

I'm old school.... What do your plugs look like?

Also.. and I have no idea about this.... is your readings by chance not "smoothed" as much as some of these others? Sometimes on a data logging devise there are spikes all over the place and the software has smoothing features to show a more general curve. I donno... just a thought.

Rich