3 to 8 maybey 10 but not likely
cat back? 12hp/12ft-lbs.
depends on rpm, intake and exhaust, manufacturer,type of fuel etc..
I would say it all depends on your intake and exhaust system. I run mine with stock headers, nismo duel rai and 60mm invidia n1 exhaust...runs great with stock headers.. remember, just because it is aftermarket does not mean better...
maybe 15 horse or so if your lucky.
Headers are aftermarket replacements for the exaust manifolds. They are the parts bolted directly to the heads on the sides of the motor. They channel the exaust from each cylinder down to the exaust pipes.
Little if any
The price for a new exhaust system for a 1995 Pontiac Sunfire is between $110 and $253, depending on the brand chosen. The MagnaFlow is one of the more expensive brands.
eight hp
keep in mind flowmaster mufflers are chambered. so they wont flow nearly as good as say a magnaflow would. so you will get more HP with a magnaflow than a flowmaster unless you put a flowmaster outlaw series on. its pretty much just a street legal way of straight piping your truck it will flow way good but it will be loud cause there is no ceramic glass packing like magnafow has.
you wont gain any horsepower, you will just gain more noise
15 to 20 horse.
Yes It does how much h.p. is gained depends on the type of system you get.
200 horsepower ( 215 horsepower with dual exhaust )
It depends on your vehicle and the type of exhaust you buy.
cat back? 12hp/12ft-lbs.
Not enough to even notice.
According to the 1999 Ford Crown Victoria Owner Guide : With single exhaust ( 200 horsepower ) With dual exhaust ( 215 horsepower )