E30 Zone

I have an E34 518i M40 engine. (as well as a 325i beast)

I was thinking about turboing this engine.

The object of the excercise is to have a low cc turboed car with a good spread of power and good fuel economy.

Striaight away im thinking bmw do a 318tdi ?

if i use the same set up on the tdi, this should give the correct amount of air for the displacement ?

The m40 is slated quite a bit, but its never tuned to the extreme.

Has the m40 been turbo-charged before???

From my (admittedly limited) experience of diesel turbos, they seem to be smaller for a given engine capacity than those used on petrol engines.

Presumably this is because diesels don't rev as high and as such don't pump anywhere near as much air as petrol engines.

The other thing to consider is that turbos from diesels are generally designed to run much cooler than petrol jobbies so any kind of high performance application where a petrol engine is feeding into a diesel turbo could lead to overheated (possibly melted) turbo parts

Not quite sure how you're gonna improve the economy with a turbo TBH, but a decent increase in power shouldn't be too hard as long as you plan your system properly, starting with how much power you want and working on from there