SB7019
While you are correct in A. the leaf spring cars are very different in frame, track weight etc and B. in your assumptions vis a vis wheel differences, my ex CSX 3327 Street (- not a replica/extension or copy), 427 owners manual calls it this way "track front -53*96 standard & racing" (writers note: I assume that the 54 point 96 refers to the measurement)rear 53 standard and 55*1/8 racing. In the rear are different part numbers for the carrier, hub & calipers for standard as well as racing. I honestly cannot interpret the drawings in the manual, but I can not imagine why there would be differt part numbers for the same parts if the specs were the same.
Now , my AK states "track - front 56", rear 60". (Some of the other dimensions are different such as overall length for nose extension, weight for the "improvements", cockpit size & etc.)I have not examined the all period magazines I have, the ones I looked at agreed with my AK owners manual for an 86'.
I have cross referenced parts between the two cars and find that the above rear suspension parts are not directly interchangable. I further have been advised that the Frua was an extension of the 427/428 coil suspension car, but that new uprights were done to increase the track, (it is possible that I've been misinformed)to impove both the look, road ability and clearance issues in the beatiful Frua coachwork.
It is my understanding that these rear changes were kept in the MKIV to allow for mufflers (silencers for those over there) to be fitted for US approval in the rear wheel wells.
While I can not, with any authority comment on what Kirkham has updated or improved on since they began (except to build the most sincere XXXXX of the type in various configurations). I heard at one time that they used a 427 SC for their digitising...if so the track should have been in the above spec area as stated.
It is possible for the back space to be the cause of the track growth, but then why change other parts? Could some of this been to improve the adjustability of the alignment that was a bear on original 427's and while is more aqdjustable on both Frua's and Mark IV's it a job in itself? Unless we can dredge up a Hurlock or Ford engineer who did the design work on the 427 suspension, we may never know. I would defer some of this lore/urban legend to MKIV "a legend in his mtinmde"
I'd love to know the correct answer and it has nothing to do with "4" inches in my dreams.
Jim
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