Mallett’s mental meanderings
Iam the first to admit that my current Porsche venture may be an exercise in mechanical futility. Way-back-when, in 1923, renowned mountaineer George Mallory was asked by a New York Times reporter why he so much wanted to climb Mount Everest, he responded with the words that are so often used to justify an endeavour that appears to have little point, ʻBecause itʼs thereʼ. Thatʼs all I can say in defence of my assembling of a Judsonsupercharged 356 engine: ʻBecause the bits were there.ʼ Having said that, there was obviously a degree of premeditation involved as the ʻbitsʼ didnʼt simply materialise as if by magic in the back of my garage.
It all started when I was just commencing my fascination with all things Porsche – the actual date eludes me but it predated ownership of my first Porsche, circa 1967. At the time, as I knew no one with a Porsche, I thought it wise to brush up on the subject and I sought out a book.
Somehow I stumbled over a slim volume entitled Porsche Guide by Sloniger, published in 1958 in New York at the reasonable price of $1.95 (I still have it, in mint condition.) My copy was secondhand and Iʼd be surprised if it set me back more than a few bob. (Shillings, for the benefit of you callow youths reading this.) Jerry Sloniger would, of course, become one of the most prolific producers of books about Porsche.
Having absorbed the differences between various models – not many as this, remember, was written in 1958 and the model line had not progressed beyond the ʻAʼ – I moved on to the chapter entitled, ʻSomething Extra – Bolting On Extra Power ʼ.
Given that I didnʼt yet own a Porsche, this was a somewhat academic and indeed optimistic exercise. However, an extended description of the substantial ʻfreeʼ horsepower to be gained by bolting on a Judson supercharger both impressed and intrigued me. Superchargers conjured up images of the pre-war battles between Auto-union and Mercedes and, shortly after becoming a Porsche owner, the hunt was on for a Kompressor.
The VW version of the Judson supercharger was introduced only two years before Sloniger wrote his guide and, with the passing of time and a little more knowledge, itʼs become apparent that his description of the Judson in relation to a Porsche engine was purely theoretical and probably extrapolated from Judsonʼs VW fact sheets.
Sloniger ʼs lack of hands-on familiarity with the Judson can be surmised by the fact that the illustration in the Porsche Guide shows the supercharger, with carburettor attached, rotated through 90 degrees, turning the downdraft carburettor into a sidedraft!
The VW motor was designed with a built-in ʻgovernor ʼ in the form of restricted breathing, limiting its revs and allowing it to run more-or-less flat-out for extended periods. When the Porsche engineers embarked on their ʻown brandʼ sports car using the same engine, they immediately liberated extra horsepower by modifying the cylinder heads with twin ports, twin carburettors and larger valves. Porscheʼs mods upped their first 1100cc version to 40bhp, and 44bhp in the 1300cc engine, compared to the Beetleʼs 30bhp.
The Judson brothers introduced their supercharger in the late 1940s, initially for the hot rodder ʼs favourite, the Ford flathead V8, followed by a version for the MG TD. In 1956 they introduced a Judson for the horsepoweranaemic Beetle, which they claimed would increase the VWʼS horsepower by up to 50 per cent. Contemporary road tests certainly indicated significant gains in horsepower, better acceleration times and an average top speed increase of 8mph. There is even a contemporary report that Judson was bench-testing an application for the Porsche, but I can find no further evidence that this led anywhere. Did they abandon the mission? And if so why?
My worry is that fitting the Judson requires losing one of the Porscheʼs carbs and Iʼm unsure if the blower will actually blow enough air through the system to compensate. (Editor Seumeʼs idea of fitting TWO Judsons is amusing and intriguing but, of course, totally impractical.)
Courtesy of Steve Kerti, the engine is up and running on a test rig – and certainly seems to run OK – but fitting it into the back of my ʼ52 356 might be a challenge. Not only is the combined assembly taller but room also has to be found for the ʻoiler ʼ.
This is a quite large bottle device that drip-feeds a fluid that goes by the name ʻMarvel Mystery Oilʼ into the body of the Judson to lubricate its whirly bits. Another downside is that the Judson adds 17lbs just where you donʼt want it on an early Porsche – another reason for avoiding the Seume route.
Sloniger ends his section on the Judson with some words of caution, ʻThere is always the possibility that you will install a supercharger and find that you arenʼt getting what you expected.ʼ As Iʼm expecting less than what I started with anything over the factory quoted output, however small, would be a bonus.
Sloniger issues another word of warning (thereʼs rather a lot in the book) which, having failed to heed, may just be waiting for me a few miles down the road – ʻBefore adding too many new ʻwonder partsʼ remember that every item added is one more thing that could go bad at the critical moment.ʼ When those parts are not ʻnewʼ but pushing 60-years old one suspects that the critical moment might only be a few revs away. Time will tell. CP
“THIS WAS A SOMEWHAT ACADEMIC EXERCISE…
PS. If anyone who happens to be reading this has fitted a Judson to a Porsche 356 engine, please get in touch!
As if he didnʼt have enough to worry about, Mallett contemplates installing a Judson…
Many would describe Delwyn Mallett as a serial car collector – one with eclectic tastes at that. His Porsche treasures include a pair of 356 Speedsters, a Le Mansinspired Pre-a coupé and a 1973 Carrera RS. Some of them even work…