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MG MGA - Judson performance?

Hi All, I have been offered a "new" Judson, never been installed, for my 1600MGA. I have read the arcives in total with mixed feelings. Some like it, some have heaps of problems. I use my car daily and love hooning off over weekends and wondered if those with experience of superchargers on MGA's could comment on my demise. I haven't asked why the gentleman never installed it to his immaculate MGA Mark2. Will ask next contact with him. Are they worth the "hassle" and the reduced engine wear? I don't intend taking it to the red line(I don't do that now) but may not be able to help giving it a go from time to time.
Oh yes. I'm also 'original" orientated so have not considered Moss etc.
David Godwin murphgod@hotmail.com
D Godwin

David,
Quite a few years ago a friend of mine played around with a Judson I think it was... vane type blower without much success. He is not the sort to give up easily and may still have it in Perth. I drove in the car a couple of times, but was not impressed with the power compared to a well sorted 1800 also it was very noisy.
If this is the screw type supercharger then noise is much less a problem. I believe ex MR2 one's are really cheep now and much easier to control. No need to heat the carb and alike.
Contact me offline and I can give you his email address.

Hope this helps.
Cheers
<MARK>
Mark Hester

David; I had a Judson on my 57 A for one season. As u know, it is a rotory vane style compressor. I bought it used, rebuilt it with new vanes, bearing and seals. It hadn't a crank shaft pulley, so i turned one out of aluminium,made it 10% larger than stock, added a speedi sleeve for the crank seal (MGB timing cover). The performace was impressive, on a par with a TR3/4. It made a hell of a noise, and I don't hear so well anymore. I removed it because i could never stop the overheating. I think a new Moss supercharger would be a better choice from a technical standpoint,a Judson however is more period. good Luck in which ever way u go. Bill.
w.g cook

Maybe the noise is the reason it was never fitted?!?
Mark, please could you give me your email address, and Bill, did the overheating problem go away when removing the Judson? I don't have an overheating problem at the moment. Did you fit another sourt of supercharger?
Dave
David Godwin

Dave,
Sorry thought my email address was attached
markhester@hotmail.com
Also note that for supercharging low compression engines are more of an advantage, as there is more volume to compress, thus bigger bang and more power.

My friend Dave had to ware ear plugs when driving also. He had more trouble with the carburettor freezing that overheating though.

Cheers <MARK>
Mark Hester

The improvement in performance is modest at best - your 1600 will feel like an 1800 - big deal.

Most people I know that use them do so more for looks - a really neat period accessory. I would not call them a serious performance option.

BTW, mine never produced as much noise as you guys are talking about - maybe something to do with being sure the oiler has sufficient output?
Bill Spohn

The Judson guru is George Folchi in Conn. in the N.E. of the US. He rebuilds them and has a machine shop for all of the parts including decals. He also has information on performance. The other person to contact is Carl Heidelmen in Mich. also in the N.E. He has done dyno testing of both the Judson and Moss superchargers. He currently runs a Judson on his MGA. He should be able to e-mail information on both units. You should find his information in the archives The noise is not that bad unless you do NOT have oil in the unit or it is not adjusted correctly. I have a Judson on my car and you have a lot more torque and can drive in a higher gear at low speed. The pick up on my 1800 with the Judson is strong and fast.
JEFF BECKER

David, After removing the Judson, I refitted the original SU's and the constant overheating went away. Bill.
w.g cook

The Judson will create more heat. I elimated the problem by the common things, grill bent to allow more air in, felt pad, coolant recovery tank, larger radiatior, blanking plate plus thermostat and a electric fan if needed. I went out this last Sunday in 85-90 degree temp and did not have a problem. Temp went to 200 degrees max. climbing mountain roads and pushing it a little. I now do not have a overheating problem. My compression is 7.5-1.
JEFF BECKER

Hi Guys, I know its an emotional thing to fit this kind of accessary but, thats me. I don't mind if it dosen't throw my head into the boot (trunk) but if it gives a noticible increase of acceleration without undue noise, unreliability nor overheating, then I'll definately consider fitting the Judson.
Thanks for all the comments
Dave Godwin
David Godwin

Dave,
I don't know if you have seen this, but it is a road test from Road and Track done in 1958.
http://www.infostuff.com/carstuff/mgacbc/mgajudson.htm


Jeff
Jeff Schultz

Hi Jeff
Yes, I have seen that article and wondered if it was neutral or biased. It certainly spurred me on to consider this option to "tweek" my A using original equipment. The overheating and noise that some people have experienced is a concern though.
Dave
David Godwin

Took my MGA out last night for dinner, (not the car..my wife) and it was a great drive. As I have said before the noise is not that loud unless you are out of oil. Since it was night, the temp bearly reached 160 degrees
JEFF BECKER

I have a 1960 MGA 1600 with a Judson. I had George Folchi make me a custom pulley to get 10 lbs boost. It went from about 45 HP at the wheels to about 80. The power band was actually lowered about 500 RPM, making much more low-end torque (no more downshifting to 2nd gear around corners--just stay in 3rd and pull away). Before and after the Judson, the car runs about 190 degrees, even on 95 degree days.

As well as my own and customer experience with Judsons and Moss superchargers at the shop, I take a lot of tech support calls both setups. The Judson can be made to work, but it's fussier. The Moss is more refined.

The key to Judsons and Moss superchargers is in the compression ratio (I like 8.0:1) and tuning: Timing, advance curve, and Air/Fuel need to be spot-on.

--Carl
Carl Heideman

This thread was discussed between 01/06/2005 and 06/06/2005

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This thread is from the archive. The Live MG MGA BBS is active now.