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View Full Version : HELP Tuning with no wb? 4.8 with big cam!



T&A Custom Rides
January 26th, 2012, 04:57 AM
Made the mistake of putting my cam in before I got a wideband. Truck wont idle and is almost undrivable. Super rich. I need some advice on how to get it tuned without a wb for now. Kinda new to tuning, any help would be appreciated.
Engine is:
Stock 4.8, Longtubes, CAI, 236/236 .617 .608 112+4 cam

Taz
January 26th, 2012, 06:34 AM
Hello T&A,

If the engine is still in the OEM truck, that's a lot of cam for a little 4.8 L in a heavy vehicle. What year is the truck ? LS1-B PCM or E38 ?

You can't do much tuning (that is accurate) without a WBO. As a start, increase the idle RPM by 250 or so, and try increasing the idle airflow in small increments until you see an effect.

Once your WBO arrives you can begin tuning with a measured input.


Regards,
Taz

T&A Custom Rides
January 26th, 2012, 07:30 AM
Yeah its in a 4700lbs truck lol. I'm going 11:1 with ported heads later this is just the first step. Its a ls1-b.

Taz
January 26th, 2012, 12:33 PM
A WBO should have been your first step. As you have discovered, once you start replacing "hard parts" the stock calibration may not be able to compensate - and driving, or even idling, becomes a problem.

Read the CALC VET tutorial and the AutoVE / AutoMAF combination tutorial. Once your WBO arrives either of these tuning techniques should get you rolling again.


Regards,
Taz

minytrker
January 26th, 2012, 09:40 PM
No offense but I think that will be a pretty poor choice for a cam in a 4.8. You really need a WB but there are several things you can try and see if that helps while your waiting on the wb. Did you make any changes to the VE or airflow tables for the cam?