Supercharging the bus part 2

So I've been busily chipping away at developing the supercharger kit. I pretty much ironed out the design and started getting materials together to build the prototype. I also took the bus to West Torrens Dyno to get the 'before' baseline power readings. It was pretty comical seeing the bus on the dyno.

It was even funnier when I got the results - a whopping 39.8 hp at the wheels (an estimated 51 at the flywheel) WOO HOO. At least the only way is up!!

I also had a bunch of flanges laser cut for the supercharger and the carburettor. I opted to get flanges cut for both Weber and Dellorto. I also bought some mandrel bends and pipe so that I could make a start on fabricating the prototype and also put together a few kits. The layout is pretty simple with a new manifold cross pipe connecting to a 90 degree bend from the supercharger. The inlet side is simply a 2-into-1 merged manifold to connect the Dellorto directly to the inlet of the supercharger.

I made up a jig to make cutting the pipes for the inlet manifold easier. This took a little bit of trig and some trial end error to get right but now I can replicate the manifolds over and over and get them the same each time. 

I'm pretty stoked with how they came out, my welding leaves a bit to be desired but I figure I can easily tack them together and then get them welded by someone who know what they are doing :D

My Dellorto also arrived and after determining the best location and orientation for the supercharger I fabricated a stand out of flat bar. I've tried to keep the supercharger and carburettor completely horizontal, partially as I guess the carburettor would work best this way but also as it looks a lot nicer is things are lined up properly. I ended up having to mill out a slot for the tensioner bearing, eventually this will be laser cut along with the rest of the stand. The stand needs to be refined a little and I will also make the final version a bit funkier looking

With the stand finished I started to assemble everything. and have a bit of a trial fit. With everything fitted I came across a few issues which I addressed and will do a little differently in the final version. Making the prototype has allowed me to be a bit more lenient with the design which has meant that everything has come together a lot easier. If I was only building one of these for my own car I would likely have taken much longer as I would have wanted to get it right first time. With a prototype I can simply weld extra bits on / cut bits off and it doesn't really matter. Once everything is tested and working I will simply measure everything up, draft it in AutoCad and then get it laser cut. 

One issue that I have had was sourcing the belt tensioner. I originally wanted to use a generic tensioner bearing from a production car but this has proven not so easy to find in the size that I want. I had some crank bearings knocking around from my DKW so I used these for the mock ups.

With the basic mock up finished I finalised a few details such as the throttle linkage and adding a bung to be able to fit a pressure sensor in the manifold and then took everything apart again so that it could be painted ready for final assembly. I couldn't resist taking a photo of the complete 'kit'. This is pretty much as I hope to supply it. Turn key - everything you need from the air filter to manifolds. 

I'm pretty stoked with how things have turned out, now all I need to do is fit it to the bus and see how much power it generates.