Period correct supercharger?

[max-o-matic]

Hi everybody,

im looking into ways to supercharge my mk1 850 but would like to use a period piece of kit...

first of all most of you are going to think "huh supercharge an 850? why, just throw it out" but no, i need to keep the original engine, mostly cause a supercharged 850 would be fun and different, but also for legal purposes...

anyway, i've looked into the infamous Shorrock superchargers and read A LOT of mixed reviews, most of them saying they were usually missing a thousand parts or were worn out, and in any case were not worth anything compared to turbos etc etc.. Then I read a few positive accounts of the beast and this got me looking for one. Well there arent any available to begin with, and when one of them is, it is either missing major parts indeed, or simply require you to go rob a bank on your way to pick it up...
so unless a case of huge luck (finding one buried in a sealed box in a field or something) Shorrock is out of the question...

So what other superchargers were attached to minis back in the day? I know that VWs were "often" equipped with Judson superchargers, and have found a few articles here and there that say those were seen on Sprites and other A-series associates, but I couldn't find anything about a judson supercharged mini... does anyone know if this is possible (bonnet clearance-wise, power-ratios etc etc)??
Were there other brands back in the late '60s-'70s that equipped 850 minis?

thanks for your insight..

Max

[cheleker]

Mark will be able to fill you in on this one. He ran an early blower on an Estate for a while. He wasn't foolish enough to let me drive it, but I did get a ride. Felt like a standard 1275 in power, but had the smoothness of an 848.

[59fan]

I'm pretty sure a Judson won't fit in a mini. Well not without some serious bulkhead work anyway.

If you want period then its probably best to hang on for a Shorrock, I've run a Shorrock 850 and its hilarious, it was running a 3.4 diff so acceleration to 30mph wasn't especially quick, but after that it flew, and the top end is frankly silly.

Ian

[mk1]

As has already been said I used to run an 850 blown Traveller. It was a good conversion, and contrary to what some people will tell you the C75B was designed for the 850 A series engine, not the bigger alternatives.

As you have already realised finding a good blower c/w all necessary parts is the hard bit.

Ebay is a good source, but you will need around £1000 & only bid on ones with some sort of warranty, avoid BCSC like the plague,I know too many people who have been ripped off by him. Sadly Ian Bishop of ShorrockSuperchargers.co.uk is no longer with us so he's not an option.

Please feel free to ask any other questions that you may have.

There was a member on here who was offering a complete kit a while ago, I don't know if he still has it. Do a search for "newtune"

Hope this helps.

[Pandora]

If you want one to rebuild, my pal has 3 (I think, 2 small, one large) and he might consider selling one. He is going to put one of them on his '61 car (one day!) but I'm happy to ask him about the others.

I know he has the bits and bobs to fit it to a Ford engine rather than a Mini, so you'd need to source all the manifolding and brackets, but the blower is the big bit, and as mark says, a lot of the other bits and bobs can be found on evilbay etc.

I think he found a source for the bearings etc needed to rebuild them, but beyond that, I'm not sure.

Anyway, let me know if you are interested, and I can give him your details if he's looking to get rid of one. After all, how many does one man need?!?

Al

[mk1]

The bearings are all standard parts, the difficult bits of reconditioning / restoring Shorrock blowers are as follows;

1. The bronze bearing / plate carriers can have new bearings fitted but can't have new blades fitted without a heck of a lot of work.

2. Balancing the entire unit is a nightmare requiring special equipment over & above the usual dynamic balancing stuff.

3. The blade to body clearances need to be very close (4 thou if I remember rightly) & this can't be achieved by machining only, you have to replaced the blades, see item 1.

Other points of difficulty are the oil feed system, the oil restricter pin has very find (+0 - -.00025) if the pin carrier is pitted the blower will smoke like the red arrows even if all other factors are OK.

As I say, they are good if you can find a good one, but rebuilding / refurbishing is difficult, but not impossible.


My Traveller

[max-o-matic]

Thanks for the tips guys, It does seem like Shorrock is the only way to go..

@Mark: I've just sent you a PM with a few questions, thanks a lot...

@Al: Yes I am interested, would you please ask your friend? As he plans to fit one (one day) I suppose he also knows how to fix them? or are they in good condition? I would obviously try to avoid a full rebuild as Mark freaked me out with the balancing difficulties, but since pristine ones are hard to come by it's forth asking about... thanks,

Max

[Pandora]

will do. I should be seeing him over the next few days

Al