Of course this could lead to another one of my favorite corrals: horsepower vs torque. Which is more important?
horsepower is a function of torque. tq x rpm/5,252
some modifications have proven to either hurt performance or gain nothing over the previous set up (be it stock or another aftermarket peice). most pollution controlled cars have within their factory tune, catalytic convertors and the smaller environmentally friendly pipes for the exhaust and air intake. with that said, with some modifications its gonna throw the tune off, and viola a seemingly large loss of power. although the parameters within the tune are usually somewhat broad allowing yous ome room for particular mods. with that said some ppl pick the corrrect exhaust setups as to not throw that tune off much and u will feel some difference. although i've never been fond of ppl following the butt-ometer as ur average joe wouldn't actually even feel the difference in a 10hp gain (then again if i went with buttometer id have lost money at my shop
) most of what people feel after new modificiations is somewhat of a placebo effect. its not that their car isn't actually running better, but typically the improvement is not nearly as much as they "predict" with the aforemented self dyno.
i've run a little over 1400 cars on various dynos at the different shops i've worked and owned, and tuned all but around 20 of them. I'm not an expert by any stretch of the imagination, but i am a realist and have seen it first hand, alotta major mods such as a full exhaust or larger air intakes, tb's intake plenums etc should be tuned. but soem of it is actually unnecessary for ppl looking to do only a few mods here and there, say for the purpose of having a better sounding car and some more mpg. with that, snag a set of 24 or 30 lb injectors (new prefered), get a cai, do some exhaust worka nd have someone DYNO tune it (not that mail order **** which i will admit some aren't too bad) u'd be suprised what this 4.6 can do with just that minimal amount of stuff.
sorry for the novel, just wanted to get everything i thought when reading over a few of the posts