2kta--89formula

iTrader: (2)

I am going to be installing some gutted cats on my car and I have O2 sims on the way but it might be a couple days before they arrive. Will it hurt anything to drive around without the sims? I realize that the engine light will come on, but will it affect drivability <timing, fuel, etc...>?

hpjunky98

iTrader: (3)

no i think the ses will just be on..never heard of anything else happening...

soundengineer

iTrader: (16)

No issues...but you will most definately have an SES light....
It is safe to drive without your rear 02's...I drove mine for 3 weeks like that because of a shipping mistake

OnE Ls1 2 HaTe

i had my cats gutted and never got o2's sims. u might run a little rich....

blcblurry

wont it cause your car to run too rich and possibly burn a whole in the top of your pistons?

psykoTA

iTrader: (4)

No, the rear O2's monitor the cats, thats all. They do not affect the fuel or timing. They just tell the comp if the cats are working or not.

soundengineer

iTrader: (16)

actually...thats kind of a myth...especially with a computer controlled car....

old school carburated cars...yes...you usually run a little rich.... even the first few computer controlled cars you run a little rich....
but with an ls1...you dont run rich....you run stoich..14.7 its always looking at your first pcm....all the time...and WOT is determined by your tables in your pcm...which is around 12-13ish

i

psykoTA

iTrader: (4)

I think people confuse rich for running dirtier. Without cats, your emissions will be higher, i.e. more HC in the exhaust, and HC are unburnt fuel. So you are not necesarrily running rich as now that you have no cats, there is nothing to burn up the extra unburnt fuel.

Now adding LT's tends to make the cars go slightly richer I believe.