Hey all, anyone know of any mod's i can do with my 89 300SEL to bump up the horsepower? Anything at all would help, little by little by little No i'm not looking for NOS =P Thanks!

Not off hand except modifying the exhaust. (Possibly a Remus if it fits the application, I know it does for a W124 6 cyl)

Better of putting in a 5.6L V8.

...you may wish to do a search using your engine type: M103?

off hand, though, I don't recall much magic can be applied for cheap $$$ HP gains on M103 and M104 motors/ chassis...

even sliding just a rear resonator (amg,brabus,lorinsor,etc) may not provide significant HP gains especailly if the motor/ trans/ chassis is tired- a first priority would be giving these matters attention

if your looking to increase drag race performance, a rear end gear swap may be worth looking into, if you're looking to increase top speed- its pretty much set up already

no disrespect, but after all one must recognize, the HP to weight ratio and its a MB luxo-cruiser machine

...would the 560SEL performance of that vintage suit your tastes? if so, that's probably where would you need to go keeping in mind that the 300e (vs. 560SEL) was just as fast if not faster/quicker (and all these lag vs. today's mid-level performance)

-fad

Simple, sell the 300SEL for $5000-$6000, buy a 560SEL for $8000-$10000. DONE. Instant reliable HP.