[lawnman]

If I take my cats off, does the fuel mixture richen up right away or does the check engine light have to come on first before it richens?

Secondly, when I do take the cats off, can I buy a VEC1 to correct the problem or do I need to buys the SIM eliminators? Will this take care of the smell also?

Thanks for all the help!!!

 

[SUN RA KAT]

You'll probably need the SIM eliminators, but the VEC1 will help with fine tuning your Viper afterwards. The VEC2 can give you a lot more fine tuning and HP, but I hear it will be around $1000 and also requires dyno figures to get it tuned specific to your Viper. The VEC2 comes with the Roe Supercharger, which is the best thing to happen to my Viper. If you're not in to spending a whole bunch of money on your Viper (yet), the VEC1 is a great mod because it does what is claimed for it and you can tune it yourself while driving it on the street rather than having to go to a dyno. One other thing about the VEC1 is that if/when you go to the VEC2, either alone or ideally as part of the Roe Supercharger System, the VEC1 will transfer to whatever vehicle you have for your daily driver. I have my VEC1 in my heavily modded Ram pick up and it gave me better gas mileage without loss of power (I was running way too rich before the VEC1).

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[McGuireV10]

You'll get more out of setting up a VEC1 on the dyno than you can setting it by feel.

It won't take long to throw a Check Engine with your cats off -- as Kenny notes, you have to buy cat sims. The sims won't take care of the smell, they just trick the engine computer into thinking the rear O2 sensors are running at a higher temperature (lower resistance) than they actually are.