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MG MGA - Judson Supercharger

Just few words to tell that I've just finished the installation of my Judson yesterday in my MGA .

Some adjustements to the timing will be need to make it running perfect . With the original timing setting , the motor tend to overheat and the radiator overflowing . So i think the timing will need to be reajust .

I have make some turn around the block and it is running perfectly .

Jules

MGA 1600MKII 1962
Jules Desbiens

Pictures?
Andy Bounsall

Welcome to the club. My Judson is lying on the garage floor waiting for a car and an engine to turn up.....
dominic clancy

And there is pictures

Before


Jules Desbiens

After


Jules Desbiens

And now installation completed ,

Jules .


Jules Desbiens

And again


Jules Desbiens

one more


Jules Desbiens

And the last touch


Jules Desbiens

Forgive my ignorance Jules as I know very little about the Judson supercharger (or any other type) but can you explain the purpose of the canister that is shown fitted on the front of the heater shelf?

My guess would be that it could be a type of fuel "swirl-pot" or maybe a type of brake servo that I havent seen before.

Less likely I know, but it could be a Nitrous Oxide injection kit to shake off those pesky Porche 911 turbo drivers who think they should overtake! :)

Let us know how the car goes Jules.

Colyn
Colyn Firth

Colyn,
That is the Marvel oiler for the Judson. Since the vanes physically contact the blower walls, they need lubrication, or you'll not get too much supercharging for very long. Note that the MGA typically has the oiler on an aluminum rocker cover, which is almost made of unobtanium. Jules, that is a nicely installed setup.
Mike Parker

Colyn ,

The canister is a reservoir to supply oil ( Marvel Mistery Oil ) to the Judson to lubricate it when running .There is a Marvel oiler mounted on the top .

It is replace the Judson valve cover who have a oiler on the top of it . In my case I don't have the valve cover , so I found this original equipment .


If one day , I ever found a Judson Valve cover , I will put it on my car but for now this is a correct solution .

Thank's

Jules .



Jules Desbiens

JULES. What part of Quebec are you living at?
Sandy Sanders
ex SHERBROOKE
SANDY SANDERS

Yes Sandy , you got it , I live at Sherbrooke . I am about 20 minutes from the Vermont Border .

Jules
Jules Desbiens

That looks great Jules. Will you be at the Brirish Invasion in Stowe next month with the car? I'd love to get an up close look at it.
Andy Bounsall

Andy , thank you for your comments . I will not going to Stowe this year because we will be in vacation during the same time but far from there in New-Brunswick for 2 weeks .

We plan to get there next year with the MGA , maybe in the class Concours d'Élégance but I have to prepare it as well .

You are welcome to came to see it here anytime , it would be a great pleasure to meet you .

Jules .
Jules Desbiens

Beautiful job, Jules! Not to worry about being unable to get down to Stowe; we can drive up to see it in NB. Were are you staying? ;-)

Ken
Ken Korey

Actually, to be totally original, the Marvel oiler that Jules has was installed on the prototype Judson for the MGA, which seems to have been built around the TF version and used this oiler on the shelf as well. In that application it was mounted on its side... Pictures and scan of the article here

http://clancy.ch/Judson_MGA_2.html

But I have to say a first class job - did you do the Judson restoration yourself, or is it a George Folchi job?

I am also going to put my Visiflow float bowl on the carb this time. That's a very rare accessory for the Holley Carb, almost as rare as finding a replacement plastic accelerator pump cam.

Dominic
dominic clancy

Dominic,
An FYI, the gauge will be sent this week. I have been very (accent on the very) busy this summer,and this is the first opportunity I will have.
Mike Parker

To help with overheating by resetting your timming, run the engine up to 3300 rpm. Set your timing to 32 degrees. Your engine is set to the max timing of 32 degrees. I originaly had a problem with overheating, check your radiator cap that it is the correct one as some will fit, but will be 1/4 short so it will boil sooner. Have the felt pad on the top of the radiator and get a fan shroud if needed. I now run 188-90 My Judson puts out about 4.5 to 5 pounds of boost. It is an attention getter at car shows as many people have not seen them.

Jeff Becker
61 MGA JUDSON SUPERCHARGED
ZZZZZZZZOOOOOOOOOOOOOOOOOOOMMMMMMMMMMMMMMMMMM
JEFF BECKER

My knowledge about superchargers is limited. I presume you have to lower the engine compression ratio when fitting one. Would overheating be one of the symptoms of not doing so?

Steve
Steve Gyles

Steve

After fitting mine the already low engine running temp dropped by 10 C, so if it's setup correctly, the efficiency gain seems to more than cancel out the extra heat theoretically generated by the Judson. When mine was running too rich, I would get ice on the outside of the carb, which sits more or less where your expansion tank is.

Overheating is not a problem on mine at all.

Mike, it's been a bit of the same here, and the car has been off the road since the prang at the beginning of June. Repairs are now being carried out and should be complete by the end of the week. Just waiting then for Chris Betson to deliver my new engine.....
dominic clancy

Jules

I have set my timming at 12 deg BTDC and it runs great, temp stays between 170 and 180 on a 90degree day unless I push it or travel up a long hill, but then it recovers quikly.

My only caution is to be carefull not to advance the timming to a point where you get pre-ignition, very bad for the engine and will increase running temp.




L Caya

Jules

Speeking of Stowe, A great show I will be there this year but with my TR6

Another Picture (Best In Show)
Ken Caya


L Caya

Ken ,

I will try the same thing too 12 deg btdc . I just haven't time to do it for now , my youngest Daughter will get married this weekend ( saturday ) and there is a lot of thing to do before , during and after wedding using wedding cars tunbridge wells .

Is that in your Coupe that you put the Judson ? You have done a great job .

Jeff ,

How can you keep the engine running up to 3300 rpm and adjust the timing , did you had help from another person to keep the throttle at the desire rpm .Maybe I could have help from a friend . I will try this manner if I have not the desired result with 12 deg btdc .

Dominic ,

I have sent the Judson to George and he rebuilt only the unit and putting new bearings , vanes and new bolts . I than found a brand new Holley 1904 Visi-Flow with glass bowl carburettor and an original Marvel Mistery Oiler still in the box with all the instruction sheet and waranty papers . Put all that stuff together and that's it .

Thanks to all for your good comments .






Jules Desbiens

Yes I did use a second person to hold the rpm to about 3300rpm while I set the timing to 32 degrees . The advantage of this is not to have pre ignition or pinging. When you run your car on the road the timing will get to full advance while at idle it is not. By setting the timing at 32 degree at 3300 rpm you have set the timing for full advance so it will not ping. It will not matter what the timing is at idle
JEFF BECKER

Thank you very much for the explanation Jeff , I will try it this soon .

I probably have to warm up the car to normal temperature before doing the timing .

Thank's again ,

Jules

jdesb@videotron.ca



Jules Desbiens

Jules,

I'm another member of the Judson club, thanks to help from Jeff, Dominic and good old George Folchi. The timing advice is good, worked great for me. Like Steve, I worried supercharging with the high compression ratio on my 1622. You can find a lot of interesting info on the Supercharging BBS here, along with some good advice. After 5 years of use no problems with the Judson at all. Probably saved by the relatively low boost you get from the Judson (3-5 lbs). Picture attached showing the valve cover. Didn't realize how rare they are !

I'm in the process of rebuilding an 1800 3-main, and will be working the math on compression ratio to best work with the Moss SC unit. In the end I hope to have a "stock" 1622 with all original parts (+ Judson), and a "hot-swap" 1800 with Moss SC and 5-speed. I'll eventually dyno both and post info for comment and criticism ;-)

-Chuck


Chuck Mosher

This thread was discussed between 30/08/2010 and 08/09/2010

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