m40 modding options?

Wed Dec 14, 2011 1:56 pm

has anybody ever fitted a turbo/supercharger to an m40b16?ive got a 1990 316i and looking for more power but can only seem to find people building a turbo/supercharged m42

Wed Dec 14, 2011 2:59 pm

search for m40 and turbo you should find your answers there. the M40 is a pretty strong little donk and 318i m40s have seen 200-220 bhp comfortably but at a garage your probably looking at about 3k half that if your going to do the work on your own.

Thu Dec 15, 2011 11:28 am

im torn between an m42 or modding the engine ive got, im planning on doing it myself but im new to e30's and i will be hoping to get a lot of help from my uni lecturers as im doing an automotive engineering degree.

Thu Dec 15, 2011 12:42 pm

gibson9 wrote:im torn between an m42 or modding the engine ive got, im planning on doing it myself but im new to e30's and i will be hoping to get a lot of help from my uni lecturers as im doing an automotive engineering degree.

Hope they're nothing like the useless tits I had who were apparently 'BMW experts'. An ex is a has been and a spert it drip under pressure ;) lol. Where are you doing yours?

M42 swap will be a piece of piss, plenty of info in this section on the swap. Turboing can start to cost money very fast. I started my super charger project because the charger I was going to use was 'only £90' which quickly escalated.

Wed Dec 21, 2011 8:28 am

I turbo'd a 318i M40B18
http://www.e30zone.net/modules.php?name ... hlight=m40

Dispite what people may think, it really IS worth doing. I found it to be more fun than the 2.7 or 3.5 conversion thst I have also done. I did my turbo conversion for £1500 and £450 of that was for a full custom exhaust.

Get and insurance quote before starting the build!

Another M40 conversion http://www.e30zone.net/modules.php?name ... hlight=m40

Thu Dec 22, 2011 11:00 am

cheers for the links!
is there any major differences between turboing the 1.6 over the 1.8?ive seen a few m40b18 turbos, but none of the 1.6.
also, whats the reliability like once you have done the swap (running at sensible boost)?

rix313, im doing mine at manchester, did you do the same degree?and where did you study?

Thu Dec 22, 2011 12:14 pm

The M40B18 has a bigger capacity. I can't remember if it is either larger bore, stroke or both.

Reliability was fine at 8.5psi, but I used the wrong head bolts when I raised the boost. With the correct head bolts 14-16psi should be fine. I never had any noticeable clutch slip even at 14psi.

Thu Dec 22, 2011 8:25 pm

gibson9 wrote: rix313, im doing mine at manchester, did you do the same degree?and where did you study?

I did an ND at Wiltshire college. When it finished I got a job building cars for a company that was then bought by Ginetta so I was then living in Leeds working there for a while. Self employed now as a race mechanic which is great fun in the winter (not). Off to Dubai for the 24hr race next month though

got an R8 V10 LMS car to play with

chu346 wrote:The M40B18 has a bigger capacity. I can't remember if it is either larger bore, stroke or both.

I believe the crank is sorter.

Fri Mar 02, 2012 2:34 pm

hoping to begin getting parts together for this through summer but being a student funds are non-existant at the minute and the amount of work from uni means i havent even been on here never mind looking for parts etc.with the crank being shorter does this lower the compression ratio at all?i read somewhere that the bore is the same but crank is shorter.