[Sean Roe]

Originally Posted by cyaford

Should we start a new thread with questions other than related to the group buy? That being said, I'll ask a question here:

I bought my Viper 3 years ago and I'm the 3rd owner. I have no idea if the previous owner(s) had the pcm reprogrammed. I was surprised when I dyno'd my car, as it put down 449rwhp/470rwtq. The mods are smooth tubes, hi-flo cats, and exhaust. I expected about 420-430rwhp. Do you think it's possible to gain 20rwhp+/- with the SCT programmer over what I put down? I know every dyno is different, so maybe the local dyno reads higher. The numbers were corrected and from a DynoJet. I'd just hate to buy the programmer and not gain or even lose power.

Another question. If the car battery dies, will that affect the tune stored on the pcm when replacing the battery?

Thanks!

That's just about where it should be, depending on what "exhaust" mods it has past high flow cats. On a '97 that probably started at about 405-410 RWHP stock, you can gain 15-17 RWHP for the cats and 17-20 RWHP for the smooth tubes and filters. Add a cat-back as the "exhaust" mod and you're right on target.
What you didn't do was increase the fuel at lower RPM, which gains throttle response / torque (and HP of course) and add ignition advance in the midrange (more torque again). Those would be the biggest areas of gain, though the upper RPM will benefit from the timing and fuel changes also.

If the battery dies or is disconnected, the program will not be lost.