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oztracktuning
March 16th, 2006, 11:59 PM
What AFRs pre-cats are people aiming for when tuning Turbos LS1s?
What is a recommended curve for rpm and map ??

turboberserker
March 17th, 2006, 03:42 AM
11.5 AFR under boost is what most guys aim for. I don't know many turbo guys who still run cats, and definitely don't know anyone running the wbo2 in front of the cats -- the pressure up there would kill the sensor in a hurry I'd think.

kbracing96
March 17th, 2006, 09:18 AM
I shoot for around 11.5-11.8 with about 17-18* of timing on my 4.8. I'm geting a meth kit next week, so I will see if I can run a little more timing and some more boost as well.

I run my wideband in the rear of my truck, right after the turbo. Worked fine when I had the cats on there, and read the same, when I took them off other then the ajusting I had to do for the increase in flow. But the cats didn't apear to make any diffreace in the reading of the WB.

caver
April 20th, 2006, 05:08 AM
The std sensors live just after the turbo on factory cars and they last just fine.her than
I personally run turbo cars between 12.5 and 12:1 I find that running richer than that loses power. Running like that with a little less advance is the same or better power wise than richer with more timing.
The richer mixtures also leaves lots of unburnt fuel pumping out of the exhaust

DJ's99SS
April 27th, 2006, 02:05 PM
Would this be the same for us SC guys? I realize the tuning would be slightly diff from a Turbo set up but are most FI set ups looking for that same general number...?

caver
April 27th, 2006, 02:44 PM
I use the same afr for turbo and sc. in vacuum same as na.