I'm gonna try to make this as brief as possible. It won't work. But, I'll try. Do me a favor, if you're NOT interested in performance mods, stay out of this thread. I'm not trying to generate more MPG here, I'm trying to make faster autocross runs. But, I hate loud cars. Both because I have significant tinnitus already, and because I don't like to attract attention to myself or disturb other people when I'm driving. So, the goal is good flow with more power and torque... but, minimal increase in volume.
I ordered the SuperCircuit header for my Mirage. It's on the way from Malaysia. I'm cheap, I'm not going to dyno this thing. But, I do plan to take some measurements. I'll get 3rd gear pull power and torque numbers from the Torque app, and 0-30/0-60 times from the same app. I can read throttle position, so I may even play with something like hand-timing 20-50 at 50% throttle in 3rd or something like that. If I can come up with something repeatable that's not "full-throttle acceleration", I'll include it. The numbers won't be gospel, but they WILL quantify improvements. And if I remember, I'll even do some exhaust sound videos... maybe take some dB measurements (my autocross club has a sound meter).
I'll take baseline readings before I start, readings with just the header, and whenever I get the exhaust done, I'll get readings with the full system.
So, stay tuned. I'll try to provide as much data as I can as things progress!
As it stands, the drivetrain is completely stock. I've done LOTS of suspension work, and I've changed the engine oil. No mods to the intake or exhaust at all.