How do the superchips perform on these older trucks? Do they give the same power increases as they do on the new trucks?

Also im gonna replace my muffler should I go with a Flowmaster Delta Flow 50 or a Magnaflow? I want as much lowend as i can thats why im leaning towards the magnaflow

 

I think if you are not changing your overall exhaust diam your low-end should be good. So muffler choice doesn't really matter imo.

chip; someone here (pre-97 land) had done a chip recently and didn't get the desired performance he was hoping for. If you haven't done pulleys yet I'd do those before the chip. Everyone raves about the pullies.