Autoblog

Comments per Volvo Leather Seats in #30.
Until the post war (WW2) leather was not thought of as a luxurious upholstery material, but was relegated to the chauffeurs quarters as a durable working surface. Oiling or waxing heavy leathers made them durable enough to be exposed to the elements. Glove soft upholstery leathers created by proprietary process (such as Connolly for Rolls and Bentley) are a recent application, but Detroit's current practice and use of heavily cracked and stiff cheap flank leathers are a poor choice and bespoke makers such as Rolls or Cadillac, Pierce, Hispano, etc. would have rejected such poor quality even for the drivers compartment.

Bespoke coachmaking era upholstery for the rear seat passengers ranged from rich broadcloths to woolens and even linens and brocades, made to order. Rarely was leather even considered unles in an open sporting body, prior to WW2.

You are correct in that cloth upholstery, if well made of good fabrics, is both warmer and cooler and often more comfortable than leather. Please, no mouse fur or synthetic "mohair" unless high voltage is desired.

Five Cylinder Balance.
With 72 deg of crank rotation firing impulses a five cyl in-line should be fairly well balanced and probably not even need a balance shaft to counteract second and third order vibrations as found in a large (1.8L-2.5L) four. The problem with three and four cyl in-line engines is the rocking and vertical moment due to the firing of the cyl at each end of the block and two of the piston-rod assemblies (in a four) running in pairs. A three cyl in-line arrangement at 120deg is qite nice asside from rocking motion, but the in-line six at 60deg counters and almost perfectly eliminates all second order vibrations. Hence stubborn adherence to the perfect balanced in-line six in such marques as BMW and Rolls/Bentley until 1958. The V6 is problematic in that it can reintroduce some rocking motion and V configurations not in the correct 120deg or 60deg bank angles produce slight irregularities in the firing impulses. Many v6s are cheap expedients resulting from two cyl "sawn off" a 90deg V8 block.

In my view the VW-Audi VR6 is an absolute work of genius, giving near perfect balance of the in-line six within the dimensions if a large four, utilizing the unique shared DOHC valve gear for superior performance any way you measure it.

A superior precision V12 such as the Packard 1932 and later "Twelve" or the Rolls P3 or Hispano is in near perfect balance, in essence consisting of two in-line sixes, and with tiny pistons and finely spaced firing impulses every 30deg of crank rotation defies the imagination in exquisite smoothness of running. Even the Cadillac V12 at the narrow 45deg cyl bank angle (designed for the V16) remained a very smooth engine due to the forgoing properties.
http://www.ukhide.co.uk/connolly.html
http://tinyurl.com/k6xrt

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