BMW K Head Throttle Body's and Plenum
Turbo Mini Forums

Hi Lads,

Ive started to think about my plenum and wondered if any of you are using the throttle body's from the k head.

I have the rubber inlets that house the injectors, I have the actual throttle body's and then theres a rubber on the end of the throttle body's

Do you use all of these parts and then mount the plenum to the rubbers? if not then what have yopu done. Pics would help :)

I’d say at least 50% of us that have done the k1100 head conversion AND turbocharged it have used the plastic intake pieces.

In the pic below you can see the plenum being built - conveniently missing the end cap! I designed the bellmouth so it has a wide flange so it was easy to locate and weld to the inner rear face of the plenum, and on the “rear” of the plenum it looks identical to the plastic pieces with the raised lip around to hold the hose in place.

http://www.turbominis.co.uk/uploads/i/wh20...bodave-4207.jpg

Edited by TurboDave16V on 23rd Sep, 2018.

I can give you (or anyone who wants it for their mini) the CAD for the bellmouth design if needed.


There are more pics of the plenum here:
http://www.turbominis.co.uk/turbodave/photos/4/

Edited by TurboDave16V on 23rd Sep, 2018.

I'd love a copy of the cad, I can give it to my nephew (CAD Designer) and get him to get them made for me. Do the bell mouths connect to the plastic inlet in my first pic above or the throttle body's in my second pic above. I think what Im trying to say is do I still use the K1100 throttle body's?

No. ITBs are simply not needed on a turbo setup; plenums with a single larger TB are simpler and well Proven.
If anyone wants it, send me a PM with your email address. So mind that my bellmouth was designed for use with 1/8” ally sheet; so you may want to tweak the thickness of the face that pokes through ever so slightly...

I got some silicone straight tubing off fleabay (bought a whole meter of it) and use the original BMW clamps (although I cleaned and greased the threads and where the ends meet and slide when tightening - it all helps to put more clamp force on them, and I’ve not blown them off yet!
There was a really neat method on the “project Binky” YouTube vids for cutting the silicone hose using a lathe that I plagiarized the last time I took my plenum off.

Edited by TurboDave16V on 24th Sep, 2018.

Thanks again Dave.

Couple more questions for you....

What are the single TB’s off?
You say you silicone pipes haven’t blown off. What psi have/are you using?

My TB is a unit off a VW 1.8t but it’s DBW so not compatible with every ECU.
Jimbo does the same as me with the hoses and he’s run crazy big boost (26+)? IIRC

Thanks Mate

PM Sent regarding CAD