bjf@homxa.UUCP (B.FENG) (12/15/84)
Hi, Review of stahl header for 6 cylinder BMW. Just installed a Stahl header set on a 3.3 liter motor. Here is my 3 day impressions. 1) Header does make more noise that stock exhaust (cast iron manifolds and thick steel down tubes). Noise is like a metallic puffing or a damped ringing. Noise is not noticable unless throttle is really opened up. Under normal hwy crusing, didn't notice ringing. In fact, car has less intake noise and hence runs quieter under light throttle. 2) Power?? Low/mid torque increase substantially. Torque above 1500 rpm is benifited. Subjective seat of the pants is 10% increase. HP increase at top end also substantial. Above 4.5Krpm engine pulls much stronger, and hp seems to fall off at higher rpm than before. 3) Fit - very good. length needed to be trimmed slightly. Fit to head was good. Installation was a pain (much better with two people). Summary, the drivability has increased (which is always very nice), and the fun power has also increased. One factor which may have biased my results is that the engine has triple weber carburators, and was a over carbed . Benifit may not be as great with totally stock motor. Glad I bought them, and would have sooner if I had know they would do this! Feng