|
Stock exhaust manifolds are often very restrictive as are non-mandrel bent exhaust piping. It would be interesting to see some performance data on the 3er or get feedback from some M3 owners. Since BMW's target market includes a niche of car enthusiasts who are interested in performance, I'm curious to know more about the baseline stock systems.
Extrude hone was a company that once would "extrude" cast aluminum runners on intake manifolds for smoother induction. This was a lot of money spent relative to neglible performance gained.
I realized that when I started having serious cylinder head modification, specialized valve work, boring and stroking motors on older cars, all this talk about adding different air filters was like telling a long distance runner to shave his legs to reduce resistance.
The compression ratio for the e90 is 10.7:1, which reminds me of some of the muscle cars of the late 60s/early 70s. In time, I'd like to see someone do some serious, but methodical and calculated modification to their e90. At the very least, the addition of quality headers with an adequate flange thickness that would reduce the need to replace the header gasket every so often, along with tuned exhaust. Yet, with the cost of BMW aftermarket mufflers already in the 1K+ range, I shudder to think what a complete system from block to tip would cost.
|