Of course, Norman---what an oversight!

I would urge everyone who has responded to this post to look at the Norman Supercharger sites, download, print and read Eldred Normans treatise on the subject. It is comprehensive and easy to follow and will answer all the questions.

Vane material in older blowers was canvas reinforced bakelite type stuff known generically as tufnol which was ok provided it was lubricated and replaced regularly. In this day and age, it would be better to look at modern materials like filled PTFE (glass or carbon filler) or a material like PEEK which would surely give better service life with the need for only minimal lubrication.
The attractive feature about vane type blowers is that anyone with a bit of design flair and a good lathe and mill can quite likely make their own.

Ah, yes of course...I knew that about the sound waves but it didn't come to me. I have heard/read the same thing that you just said 1200RC, and it could even be more feasible than my theory for the exhaust. I say this because of something Dodgeman pointed out to me that he saw from my drawings and this is that the inlet in a turbo car flows smoothly, whereas the exhaust flows in pulses. I believe what I said about the turbulence is still correct, but is not the only effect it can have.

But, think about a turbo car...the sound waves are going to be uneven anyway, or the uneven ones won't even reach the exhaust valves due to having to go back through the turbine and exhaust housing. Just a thought, I may be wrong...

I have made 3 vane type superchargers and they are relatively easy to build. I have one on my 1931 MG and they were a factory option even on the lower end sports cars of the day. Vane wear was excessive but was caused as much by poor filtering as much as the quality of the vane material. My OHC MG engine does'nt even have an oil filter just a gauze mesh filter. I use phenolic material for my vanes and they are running in 2 other cars with no trouble. They still have oilers to help them out. My car was sold brand new without an air filter on the SU carb cos there wasn't the room!! It's no wonder the service intervals were measured in the hundreds of miles.

Norman web sites? Bloody hell. The poor feller passed away in the early seventies i think & i had no idea that there were people that regarded him & his work so highly that they would create sites.

When i was an apprentice in 1966, i attended tech at Ultimo, i was doing a special apprenticeship course & i spent a full 6 months at the tech. There was a bloke with a blue '64 Holden EH sedan with a rump rump engine that drove past every morning & afternoon. One day some fool in a Daimler SP250 sports car decided he would blow him off at the lights on Broadway. They both launched,...then about halfway across the intersection the EH just exploded into action with wheelspin, smoke, noise. It was wonderfull.

Later, some of us got to know him & he showed us the engine. It was the 179, with Norman blower, with clutch. He had engaged the blower clutch just after launch to save the driveline's clutch during takeoff.

I will be checking out those sites when i get out of here. His book is a bit dated, but the theory & the physics are still the same.

Stirlingmac.
More power to you my friend. Early iron is bulk fun. Please tell me that the MG engine is NOT a 2 main bearing type. The Riley 9's of the early 30's had a lovely twin cam design with hemi type heads, very short pushrods & twin carbs, but typical of the Brits, it had a 2 bearing crank. A perfectly good design ruined by stupidity.
Riley racers carried a spare crank or two, i'm told, if they were smart & wanted to finish a days racing. They went well, but not for long.
Does your OHC MG drive its cam by a vertical shaft at the front, & if so, is that shaft a part of a verticaly mounted generator?
I saw one like that in a 1929 Morris saloon with a fabric, body once upon a time. Bizzarre!

Yep it has the bevel drive and vertical generator. The design is a good one and was the basis for the land speed record breakers from MG. With 750cc and a blower those little suckers ultimately ran to 150 mph with these engines. It is the 2 bearing design but has a counter weighted steel crank that I made to keep it reliable. The early Morris, Wolsesley and MGs all shared the same engine.

heh heh..
there's one of those Riley racers sitting in my brothers workshop at the moment. He's rebuilding the engine because the idiots who charged around $10k to rebuild it the first time stuffed just about everything up.

It's a very sick little engine, very english!! The two main bearing crank with the external, brazed in oil feed pipes just kills me!!

Chris Dodgeman!

Have a look at www.fefcholden.org.au/techinfo/supercharge
It will do you a power of good. As I said previously, this is the best exposition on supercharging I have seen (outside some Textbooks and Technical Papers)

broo mbroom

89mm
This is the book that i have. I bought it new for $1 quite some years ago.
As i have writen, it is a bit dated with it's reference to HR Holdens, & the prices that are quoted are a lot cheaper than todays values.

That said, i agree with you absolutely that it is probably the best volume on the subject around. What gladens my heart most is the fact that it's back in print, & for a price that gives you change from $10, it's gotta be the best value in town,.... after a workshop manual.
Thank you for the link.

Stirlingmac
Those 2 bearing cranks give me the shivers. I can understand it in Austin 7's, but better breathers deserve better designed bottom ends.

i just read this whole topic, good stuff... so im bumping it for yas' all to read..