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Nigel - Thanks for your comments on those wheels - I've expressed some interest in them - your comments on the offset are noted - maybe I should buy locally in case of issues with offset and them fitting properly but that will mean I'll probably have to buy them new cos they never come up secondhand, for now strand wheels will have to do.
cheers
Alastair
I know how to accurately measure & calculate wheel offset, but one cannot be sure that all vendors know what measurements & calculations to make!
My 5½ x 13 inch Cosmic alloy wheels (21 mm offset) were okay on my 1974 Triumph Toledo 1300, when fitted with 175 SR13 (i.e. 175/80 R13) radial tyres, but suffered outboard sidewall rubbing problems in the rear wheel arches when 185/70 R13 tyres were substituted
If those 5J x 13 inch "Minilite" wheels are truly of 19 mm offset, you would probably be okay with regard to rubbing if using 175/70 R13 tyres, but I would not want to stake my reputation on it and there is still the matter of complying with New Zealand regulations regarding deviation from factory-standard wheel specifications!
So far, I have driven my Triumph Toledo 1300 with several combinations of wheel, tyre and front steering and/or suspension geometry as follows, but it was with the Cosmic alloy wheels (offset = 21 mm) and low-profile, Firestone S211, 185/70 SR13 tyres, that I experienced the unnervingly rapid transition from under-steer to over-steer when negotiating bends under power!
Cosmic 5½ x 13 inch alloy wheel – 21 mm offset | Uniroyal Rallye 180, 175 SR13 radial tyre | factory-standard front-wheel camber => Very civilised, predictable steering characteristics
Cosmic 5½ x 13 inch wheel – 21 mm offset | Kelly-Springfield Steelmark, 175 SR13 radial tyres | factory-standard front-wheel camber => Very civilised, predictable steering characteristics
Cosmic 5½ x 13 inch wheel – 21 mm offset | Kelly-Springfield Steelmark, 175 SR13 radial tyres | all front-wheel camber-adjustment shims removed => Very civilised, predictable steering characteristics
Cosmic 5½ x 13 inch wheel – 21 mm offset | Firestone S211, 185/70 R13 radial tyres | all front-wheel camber-adjustment shims removed => unnerving transition from under-steer to over-steer when negotiating bends under power
Triumph Dolomite Sprint GKN 13 x 5½ inch wheels – 35 mm offset | Firestone S211, 185/70 R13 radial tyres | all front-wheel camber-adjustment shims removed => Very civilised, predictable steering characteristics
This later led me to wonder, whether the Cosmic wheels’ lesser offset (offset = circa 21 mm) in combination with the ‘original’ 175 SR13 tyres’ circa 5•5% larger rolling-radius, might have wholly or partially cancelled each other’s effects on steering offset (aka scrub radius), to retain similar steering characteristics, to what would probably have been the norm, with the original factory-fitted wheels!?! Having never driven the car, with the original factory-fitted 4 x 13 inch steel wheels (offset = circa 35 mm?) and 155 SR13 tyres, I could only speculate.
I suspect that you might have a similarly unnerving experience, if you were to fit the “Minilite” style 5 x 13 inch wheels (offset = circa 19 mm) with 175/70 R13 tyres. You would probably be okay with 175 R13 (i.e. 175/80 R13) tyres, but these are becoming difficult to obtain!?!
I shall be interested to discover what kind of steering characteristics I experience, when I substitute my set of MG Maestro 5½J x 15 inch alloy wheels (offset = 31 mm) with either 185/65 R15, 185/60 R15 or 185/55 R15 tyres!?!
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Regards.
Nigel A. Skeet
Independent tutor of mathematics, physics, technology & engineering, for secondary, tertiary, further & higher education.
https://www.linkedin.com/profile/view?id=308177758
Upgraded 1974 Triumph Toledo 1300 (Toledo / Dolomite HL / Sprint hybrid)
Onetime member + magazine editor & technical editor of Volkswagen Type 2 Owners' Club