Air fuel mixture (where to test)?

[mrviper99]

Where is the most accurate and correct place and way to check air fuel mixture? Had it tested at dyno, however he just had a tail pipe unit. Wouldn't it be better to take the reading at the O2 senser in the headers before the cats. Thanks Jeff

 

[Tom Welch]

The best method is with a unit that threads into an O2 **** in your exhaust system. It doesn't really matter if it is installed in a forward or rear ****. What I typically do is make a pull and switch the a/f reader to the opposite side of the car so that I can get a reading from both banks of cylinders. I have seen Vipers that run leaner on one bank than the other. This is a good method to insure that forced air induction and or additional fuel is being distributed correctly.

Tom
Http://btrviper.com

 

[LTHL VPR]

I would highly recommend that you weld in an additional **** to your exhaust system, and use it for measuring 02 using a high quality A/F analyzer/monitor.

We do not recommend that you remove your O2 sensors and replace with the A/F monitor O2. Depending on the bank you use (primary/secondary) it can cause your computer to make adjustments that will not represent real world driving conditions. You can even trigger a code. With over 50 Vipers in our database and over 500 runs, we know a fair amount about the computer on the Viper, how it reacts in almost all conditions, and what can cause inconsistent results.

Call if you have any questions.
-Wayne