O2 Sims?

**markzman97** · 11-02-2006, 05:43 PM

Where can I get o2 sims for 4gen LS1? Thanks!

**2001NBMZ28** · 11-02-2006, 05:49 PM

Sponsors, like thunderracing.com sell them. Or just have the rear 02 codes turned off.

**mrr23** · 11-03-2006, 05:56 PM

http://www.ls1.com/forums/sponsor.php

**Redphoenix1998** · 11-03-2006, 08:34 PM

yeah, check the sponsors for sure

**RDS** · 11-06-2006, 10:24 PM

Im looking for a set myself and I called thunderracing.com today and they told me that they no longer sold them for the ls1. I noticed jegs do not have these on their website either. Any other places have these?

**Steve Crowe** · 11-07-2006, 07:09 AM

O2 sims have come and gone on many websites, mainly because I don't think anyone's come up with one that really works for any length of time. If you read through the actual Helm's manual about how the system works you'd see that it isn't that easy to fool - just a couple of resistors will extend the time before a code is set but not forever.

My company is seriously considering producing one that can truly fool the PCM and considering I'm not seeing any out there for sale anymore I best move that project up in priority.

Will update everyone when we get something together, Ithink we figured it would take 3 - 4 weeks of development time until we could start production.

http://www.iecoklahoma.com

**89LX** · 11-07-2006, 02:58 PM

I just ordered from www.speedinc.com approx $75 for both. They are already going up in price as the Feds seek out the venders.

**2001NBMZ28** · 11-07-2006, 03:54 PM

Yeah, they're getting scarce all of a sudden...

**Steve Crowe** · 11-07-2006, 04:04 PM

In theory the Feds shouldn't be able to bother the vendors if they're labeled as for sale for "Off Road Use Only"

I mean, they still sell the off-road pipes that are specifically made to bypass cats.

**89LX** · 11-08-2006, 05:03 AM

I got mine on the way and will put them to good use. Oh….Drinking alcohol is supposed to be an “off-road use” item as well but some still abuse its sell.

**Steve Crowe** · 11-11-2006, 09:02 AM

I looked at the sims on that website, by their size they're the commonly made variety with a few resistors that simulate a 0.450V signal and a draw on the heater supply for the PCM to see. Unfortunately, while this method will fool the PCM for a while, it will eventualy throw a code because the 0.450V NEVER varies any significant amount.

The way the system works, at least on the '97 - '02 W-body vehicles, involves the PCM occasionally forcing the mixture rich for a moment and looking to see if the 2nd O2 sensor varies a bit from the target 0.450V. If it's responding too slowly it assume the cat is worn out; if it's not responding at all it assumes there's something wrong in the sensor circuit.

The design we intend to produce in future will fool the PCM all of the time as it will track the B1S1 signal and reflect it in less intensity in the B1S2 sim voltage. It proved to be a challenging design as even the tiniest load (such as from a 10 Megohm/V digital voltmeter) on the B1S1 O2 sensor slightly reduces its output voltage causing the PCM to think the car is runing a little lean.

http://www.iecoklahoma.com