V6 Aurelia Mania

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To my opinion the B-54 design could well have been the initial design FdV had in mind for his sporty B-20 Aurelia project all along. We will never know, because FdV is not anymore amongst us living and Gianni Lancia still alive but definitely not ever wants to be interviewed about Lancia & Co Automobili. But in ‟52 and ‟53 on the contrary Gianni had a great time with his “Aurelia da Corsa” (above) project, only to pull out of GT Class “competizione” in favor of Sports Car racing, obviously forced by certain AR protests against Lancia‟s not having homologated their all aluminum “da Corsa” B-20 body‟s and consequently we now understand the B-54 dry sump SOHC engines, even in thin steel B-20 chassis, being quite impossible to get it all homologated in time, without overstressing the factory production capacity building such a substantial amount of production competition cars. In fact a fifty‟s GB newly imported B- 20 Coupé was price tagged only £200 less compared to a basic Rolls Royce. Along with FdV‟s B-54 project Lancia‟s other promising designer Ettore Zaccone Mina was working on a second V6 “prova” design (right) designated B- 110. In fact both “prova” designs had “competizione” type D Series cars in mind. Why EZM didn‟t choose for, if only slightly B-20‟s deviating crank/bore/conrod relations is unclear to me, because the off the shelf 160mm conrods from the (115hp) B-20, despite being very rugged, were unnecessarily his first choice. These comparatively long conrods heavily narrowed down the DOHC and 3C (triple carbs) advantages of this almost square 80,5x81,5 block still producing 187hp. For this initially all blank “prova” design exercise EZM could well have chosen for the more radical 83,0x77,0 short stroke variant, providing lower mean piston speeds (mps) and even, with up to 145mm shortened conrods a more dynamic intake gas flow cycle should be possible since pistons accelerate earlier and faster. See about this my 3e experimental phase further below. Quite interesting to discover in EZM‟s works drawing (above) are the Vittorio Jano AR (Alfa Romeo) style mushroom actuated valves with spring coils under pretty much the same valve angles compared to the B-54 design as well as the disadvantageous second oil ring below the gudgeon pin. Clearly no provisions were considered for oversized cylinder liners to accommodate later capacity changes. Note also twin sparkplugs being quite accessible from between the DOHC‟s, providing ignition through a not shown distributor on the rear side of the left intake camshaft. The lubrication system is basically B-54 similar and probably to simplify valve distribution, a pair of gears oddly over reduce RPM from the crankshaft to a duplex chain driving all four camshafts minimizing wear and tear on the chain, only to accelerate the camshafts to the correct RPM at last with relatively smaller camshaft sprockets also enabling the bonnet lower over the block. At the crankshaft‟s rear a rudimentary flywheel drives the alternator by V-belt. The water pump is directly driven from the crank‟s front while the oil pump is gear driven downwards pairing the cam distribution driving gear. Each intake manifold‟s vacuum is balanced by horizontal ducts but unfortunately again shows about 35mm carburetor shift compared
to the valve porting of the front right cylinder, because of large float chambered carburetors taking more space than available. Despite all these efforts Gianni Lancia, though maybe not fully aware of all the restrictive factors inside his “prova” blocks, unfortunately decided not to proceed with even alone his beautiful dry sump B-54 design. He must have seen that the increased power output mainly got produced because of the better porting only made possible by absence of the pushrods. The increased RPM possibilities involving the OHC valve actuation probably had less influence because of earlier discussed flow resistance around the valves unfortunately increasing squarely to higher rpm‟s. More restrictive factors in both designs, besides limited viscous oil behavior in all main journals, big ends, piston guiding and second oil rings, would be the 15mm too long standard 160mm conrods together with the pistons free space to the crankshaft of about some 18mm and the unnecessary low position of the Ø20mm gudgeon pin in each piston, leaving about another 7mm unused in general dimensioning. Now one realizes why these bulky crank balancing lumps (see AR 8C crank in “8C Mania”) should be kept small in diameter obviously to be related to the stroke. All together this waisted space could well have been used advantageously for shorter 145mm conrods with B-20 style 26mm wide journals (today common on most VW Golf) subsequently decreasing the total engine‟s height with 25mm (a good inch lower all together !!!). Moreover in all the periods high performance engines negatively working second oil rings were ignorantly applied. Not only by Lancia & Co, but surprisingly after „56 these rings were obsolete in all GP engines after some 25 years, at least since Jano‟s 1932 AR 8C 2300 discussed in “8C Mania” of ignoring and misunderstanding the nature of these rings. (see also “Camshaft Mania” ) At last in the 1956 GP season Ferrari most gloriously seized the World Championship with the (ex Lancia) D-50 V8 GP car, however without the second oil rings as noticeable in the digipic (above) from “Classic Racing Engines” by Karl Ludvigsen 2001 and at the fabulous D-50 stunning with original Lancia badge, steering wheel and factory stamped parts in the “Museo Ferrari” (right) at Maranello, second GP Car from the entrance and quite emotionally choking finding the real car there. Both FdV and EZM have been struggling with intake canal layout from the carburetors on to the valves avoiding unnecessary curved canals. After all it was quite well known straight canals having less resistance at higher revs, so I got rather surprised
Page 1 and 2: V6 Aurelia Mania This article is ab
Page 3 and 4: With our studs and liners removed f
Page 5 and 6: external low pressure waist oil con
Page 7: Or instead even imagine for the 195
Page 11 and 12: EZM slowly tended to under square b
Page 13 and 14: Enlarging valves as an option to im
Page 15 and 16: Morini even developed their very su
Page 17 and 18: If I can do such design on the corn
Page 19 and 20: Zuffenhausen” solution (below) sh
Page 21: Francosporto‟s Related Links : Au

V6 Aurelia Mania

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