A friend of mine has a 300 SDL and wanted to know if anyone had a cost effective idea to boost the HP. Today it has a lowly 90 HP. Any suggestions?

I thought the pre-'86 300SD (was there an SDL offered? I don't think so...) had a horsepower output of 125 horsepower, having the 3.0 liter turbo 5-cyl diesel.

A non-turbo 300D (which you couldn't get in this country after 1981, and never in S-class form) has around 90 hp.

The best way to get more horsepower? Sell the 300SD and buy a 380SE and upgrade to a Euro exhaust with less restrictive or no cat at all (if you can get away with it...dunno).

If you want even more horsepower, get a 300E or 420SEL.

If the above feels lacking, get a 560SEC or 560SEL...

And then there is the 400E, E420, 500E, C32AMG, E55AMG....yeah....

How much do you want to spend?

-Sam

Well, since he already owns a S600, his version of cost effective is a bit different from mine...the older car has sentimental value. Any real ideas?

Yeah, make sure it's in the best tune possible. Short of an engine swap (to maybe a 3.0 liter 24-valve turbodiesel 6 as used in a 1998-1999 E300D Turbo with 180 plus horsepower) there aren't any major gains over stock HP to be had with MB's 3.0 liter turbodiesel 5...ask any dieselhead on this site in "Diesel Discussion".

-Sam