Uncle Alfred's Toe-In

[AC-Crankcase]

Those of you with long memories will remember our 1926 Royal 'Uncle Alfred'.  He is back on the road again after considerable mechanical restoration.  He managed the longest journey he has completed in over 10 years recently to a local village fete, all of 4 miles which he achieved with aplomb.
   
   Does anyone have any idea what the toe-in should be a the steering was a little dodgy???
   
   The restoration is to continue, with the wings being next, when I have confidence he can manage longer journeys, the coachworks is 35 miles away!
   
   All the best,
   Tom
   
   PS how do you post pictures on this forum?

[Old Crock]

I have the geometry for the SIX cylinder, so the following may indeed be useless for the FOUR! The four and six had different wheels/tyres over the vintage period but possibly AC used the same measurements, or thereabouts, for the majority of their steering designs???
   
   ·   Track: 45½ inches at road (increased to 48 inches in 1927)
   ·   King Pin inclination: 7°
   ·   Camber: 3° (or 4°??)
   ·   Caster: 6°
   ·   Toe in: 3/16 to 7/32 inch
   
   The figures above were measured from an AC blueprint I have dated 1926. The track, caster, toe-in being certain from the drawing, the camber and king pin inclination measured by protractor and may need further confirmation. It was quite common with many marques in the 1920's to change and modify the geometry, for example by using blocks at the springs, for the likes of sports or competition use. I have not seen any AC figures for the vintage cars in print, so it is worth those above being recorded here on the forum....even if maybe not correct for Uncle Alfred.

[AC-Crankcase]

Thanks for the information. I will try a toe-in between the dimensions suggested and see if it improves the steering,
   
   All the best,
   Tom

[jonto]

Rotate the wheels, and measure and allow for any run out at the rims before setting adjustment.

[Old Crock]

quote:Originally posted by jonto
   
...and measure and allow for any run out at the rims...

   Jonto, do you have a view on wheel balancing? I know your car is early (1921), before the days of balancing anything. Can the lead-type weights be fitted on your wheels or would the self-adhesive type be needed - the latter can look awful on an old car (but can be painted over), and with disc wheels you want them only on the inside. Do you have beaded-edge tyres?

[jonto]

When you have new tyres fitted today, the vender usually attends to wheel balance on the machines they all have today. In the past wheels were balanced statically on the hub, it was normal practice I think on wire wheels to drill the well, fit a nut and bolt with weights, or to twist soft wire around a spoke to add weight, I don't know how the problem was tackled on disc wheels. Modern rim weights are self adhesive, could use those. Myself I've yet to have a problem with wheel balance on a vintage car, I have well base wheels, the original beaded edge were discarded before my ownership, rotted where they stood on the floor for all those years

[AC-Crankcase]

I can't say I have ever had problems with balance on the front wheels, however it would seem best, if needed, to have the leads glued to the inside rim and painted over.  Unfortunately most vintage ACs have their wheels inside out these days so it would show!
   
   The valve should be on the inside of the 5 stud wheels.
   
   All the best,
   Tom

[AC-Crankcase]

OK so I can't count, make that 6 stud wheels!!!
   
   Tom

[Old Crock]

quote:Originally posted by AC-Crankcase
   
The valve should be on the inside of the 6 stud wheels

   Why did AC Cars, in the early 1920's, have the tyre valve on the inside of the wheel? What was the logic? Other four-cylinder ACs have outside valves - were all these changed from the inside edge? Some wheels show a recess for the valve, therefore is the recess on the inside on all the early four-cylinders, or were the wheels simply turned round so inner becomes outer? Did any other marques, early 20's,  follow this practice?
   
   Here's a couple of early 20's AC publicity shots; notice tyre valves.
   
   
   
   Here's a couple of four-cylinders showing inner tyre valves.
   
   

[jonto]

"Easyclean" wheels is I think the answer, the six studs one can be fitted either way round of course.

[luke45]

quote:Originally posted by Old Crock
   

Here's a couple of four-cylinders showing inner tyre valves.
   
   
   

   
   That's one sweet ride!