Blower Drive Pulleys
Speedweek 2016 is at the end of February which is not really too far away. Whilst there's not too much to do on the Oval there's still heaps when I take into account how little time I actually get to concentrate on one project. In addition to Speedweek it looks like the SATA are putting together a speed trial at Waikerie. This will be open to SATA members and SATA / SCTA compatible cars and bikes. This is great news and is exactly what I was hoping for except that the meet is to be held on November 18th which leaves just a shade over a month to get everything together. Now of course I'm not going to kid myself that I can make it happen, but if I put another engine in that I happen to have already built and laying around the garage I recon I might be in with a chance of at least doing some shakedown testing on the car itself.
So having gained a little newfound inspiration I've actually done a few things on the engine. The first thing I did was to finally bolt the throttle body on to the supercharger. Previously I had made an adaptor plate but had not drilled and tapped the mountings for it. This was a small job that didn't take too long to do and takes me one step closer to getting the induction side of the engine set up.
I also ordered and picked up some drive pulleys for the crank and blower. These are heavy duty jobbies that run a 25mm belt. There's no chance of these slipping. The pulleys are supplied pilot drilled which means that they are un-machined and so you can modify then to fit your application so tonight a spent some time turning the small pulley to fit the supercharger.
I also picked up a second set which I will install on the lowlight as a bit of an R&D experiment. This is the pre-cursor to setting up the EFI version of the supercharger kit that I sell. Once I am happy with everything I will look to get the new design drafted up and manufactured.
At the moment I'm not 100% how I am going to do the crank pulley, a lot depends on the cooling setup that I end up with. My initial thoughts are to use a standard vee belt to drive the cooling and the toothed belt to drive the supercharger only. I've got a standard alloy style vee belt pulley on order so when it arrives I will look to machine the two pulley so that I can bolt them together to form one single pulley. I may even make a hub for these to fit on. Early days yet.
The toothed crank pulley is slightly larger than the stock pulley, this was so that I could get the ratios that I needed without having to run the blower pulley too small. The good thing with using off of the shelf stuff is that I can buy the blower pulley in a variety of different sizes which means that I can easily dial the boost in once the engine is up and running.