[Small Triumph tyre recommendations]

175/70's are about right on 5-5.5" rims. A bit pinched on 4.5's and a bit stretched on 6's.

The Dolomite Sprint used 175/70 x 13 on 5.5" rims

 

Steel 13" rims? new Formula Ford rims in 5.5 x 13 are to be had, but at £108 each they are not cheap.

[Six Cylinder Crossflow Head?]

On 7/2/2015 at 5:28 PM, JohnD said:

An alloy copy of the OE head would save some weight, about 22kgs, not to be sniffed at, but in a car that weighs, say, 900 kgs it's not a lot, 2.4% in fact.

The volumetric efficiency improvement of cross flow offers a lot  more in performance.

Most (all?) crossflows  use an OHC which raises all sots of probs as Andy says, driving the shaft and the dizzie.

John

Its not a percentage of the overall weight, its a percentage of the weight over the front axle the momentum of the large mass ahead of the centre of mass.

22ks, give or take 50lbs would give much the same effect as moving the engine back 6 inches and would give a near 50/50 balance.

 

Millions of Ford Kent engines were crossflow

[Small Triumph tyre recommendations]

By 1968, 155/80 x 13 radials were a factory fit on the 2 litre engined small Triumphs and an option on the 4 cylinder engines. 

 

186/60 x 13 tyres are almost extinct.

175/70 x 13's are common, the right size and available in performance models. 

 

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