The Wheel and Tyre debate

[qkingston]

I know, I know, this has been covered many times and during my complete 4a restoration I looked into this in some detail; but Forum searches didn't provide an answer. A fellow member offered me a set of 15x6" KN Minators in as new condition for little money, so that decided it. After 2 years of running I'm happy with the general handling/comfort of the wheels with 195/65/15 Vredstien T Trac2s, except for the slow speed manoeuvring/parking which is hard work (obvs). So my question is; how much difference to this would switching to 5 1/2"  rims make with the same tyres. I understand that the tyre profile is also creating greater ground contact and therefore more friction, but would a narrower rim make a noticeable difference?

Many thanks

David

[John Morrison]

Hi David - nope, not a desernable one anyway 

 John

[trchris]

Hi David

I’m running Minilite 5.5j wheels with 165/80 15 and find it fine on my 4a handling isn’t as good as 195 but low speed turning is so it’s a fair compromise overall 

[Motorsport Mickey]

Hi Chris,

That's strange, the standard section 165 80 15 tyres on 5.5 wheels are the optimum mix on the TR for handling, as in change of direction and cornering inputs. The 195 tyres do give more grip for point and squirt (marginally more tyre on the road, there's about 15% of the tyre on the outside barely touches the tarmac because of the negative camber) maybe that's what you mean ?

Mick Richards

[monty]

20 hours ago, qkingston said:

I know, I know, this has been covered many times and during my complete 4a restoration I looked into this in some detail; but Forum searches didn't provide an answer. A fellow member offered me a set of 15x6" KN Minators in as new condition for little money, so that decided it. After 2 years of running I'm happy with the general handling/comfort of the wheels with 195/65/15 Vredstien T Trac2s, except for the slow speed manoeuvring/parking which is hard work (obvs). So my question is; how much difference to this would switching to 5 1/2"  rims make with the same tyres. I understand that the tyre profile is also creating greater ground contact and therefore more friction, but would a narrower rim make a noticeable difference?

Many thanks

David

I think you will only notice any real slight difference if you change both the wheels & tyres to a narrower configuration.

[qkingston]

Thanks for the feedback, I get the point about the wheel and tyre consideration. I'll probably stay is is for now, the medium/higher speed stability and ride comfort is absolutely fine with the 6" wheel - 195/65 combination

Rgds David

[Colin Symonds]

Has anyone run a staggered set-up on their TR?  My BMW Z3M runs 225-45 R17 on the front and 255-35 R17 rear.  Mind you it is running more than 320 HP.

[trchris]

Hi Mick 

yes that’s what l meant along with getting drift when caught in the tarmac tracks the HGVs make !!! 
Chris

[Motorsport Mickey]

1 hour ago, trchris said:

Hi Mick 

yes that’s what l meant along with getting drift when caught in the tarmac tracks the HGVs make !!! 
Chris

The description for a car and tyre that does that Chris is "tracking", sometimes it can be bad enough to pick up on road white markings also. Handling is a description used to describe the changing of the car attitude or behaviour to driver input.

The 195s because they are a squarer profile with the cambered inner surface contacting more, will tend to pick up road input from lines or changes in road surface HGV "ruts" in the road surface for example.

Mick Richards

Edited April 1 by Motorsport Mickey

[JohnC]

May seem like a stupid question, but please bear with me. How do modern light truck/van tyres compare with the tyres our cars were fitted with in the '70s? Here in Oz the only locally-available 165/80R15 tyres are made for vans, and all the advertising info indicates that longevity is the primary consideration. Now I realise that the horrifically expensive 165s I can get from overseas will be vastly superior to van tyres, but how do van modern tyres compare to 1970's tyre technology?

I expect I'll go for the195/65 option in the end. I had hoped to try a set of Radar 185/70 but our importer won't bring them in.

Does anyone have any experience they can share? 

Thanks,
John

[DRD]

7 hours ago, JohnC said:

May seem like a stupid question, but please bear with me. How do modern light truck/van tyres compare with the tyres our cars were fitted with in the '70s? Here in Oz the only locally-available 165/80R15 tyres are made for vans, and all the advertising info indicates that longevity is the primary consideration. Now I realise that the horrifically expensive 165s I can get from overseas will be vastly superior to van tyres, but how do van modern tyres compare to 1970's tyre technology?

I expect I'll go for the195/65 option in the end. I had hoped to try a set of Radar 185/70 but our importer won't bring them in.

Does anyone have any experience they can share? 

Thanks,
John

You could use them but the trouble with van tyres is that they are designed for much higher loads than a tyre for a car, plus the speed rating is probably lower as well. I guess it would probably be like trying to run a marathon wearing wellies.

[Ian Vincent]

Judging by the speeds the average white van man gets up to, I wouldn't be too worried about the speed rating.  What do you use your TR for?

Rgds Ian

Edited April 2 by Ian Vincent

[TR Rob]

Would imagine van tyres would give a pretty firm ride, as I would imagine the sidewalls are pretty stiff and reinforced as they have to withstand a lot of abuse regarding kerbing and carrying heavy loads….don’t ask how I know !!

[Lebro]

Yes, agree they would give a rather firmer ride than ideal !

Bob

[BlueTR3A-5EKT]

11 hours ago, JohnC said:

May seem like a stupid question, but please bear with me. How do modern light truck/van tyres compare with the tyres our cars were fitted with in the '70s? Here in Oz the only locally-available 165/80R15 tyres are made for vans, and all the advertising info indicates that longevity is the primary consideration. Now I realise that the horrifically expensive 165s I can get from overseas will be vastly superior to van tyres, but how do van modern tyres compare to 1970's tyre technology?

I expect I'll go for the195/65 option in the end. I had hoped to try a set of Radar 185/70 but our importer won't bring them in.

Does anyone have any experience they can share? 

Thanks,
John

Where is Australia and Is it near you?  

There is a business online in Australia that offer 165/80/15 Hankook regular car radials at AU$121 each. if you buy 4.

https://www.tyresales.com.au/search?search=size&width=165&aspect=80&rim=15

reviews

https://tyregeek.com.au/hankook-kinergy-eco-2-k435-review

Edited April 2 by BlueTR3A-5EKT

[JohnC]

Thanks Peter. I may be wrong, but I think the Hankook Kinergy is still one of the "long mileage" tyres. Yes, it's not a van tyre, but still not a soft compound. I'm probably being precious, as I only drive the car on the road in what I hope is no more than <ahem> a responsibly spirited manner, but I'd like a tyre designed for handling and grip over longevity. I wrote my TR6 off 18 months ago by spinning coming out of a roundabout. At 40kmh. Old tyres I think. That was scary, but I still can't afford the Pirelli/Michelin period-appropriate tyres. But the Hankook tyre is on the list. Right now, I think I'm going for a Goodyear Eagle F1 195/65. I have fitted power steering from CDD so the low speed heaviness is not an issue.

Cheers,
John

[Andy Moltu]

Old tyres can be scary and I would guess UV related deterioration would be greater in Australia than the UK. Too many people assume that low mileage classics’ tyres will be fine because they have minimal wear and no obvious cracks. However they tend to go hard, less grip in the dry and truly dangerous in the wet.  The handling/grip argument becomes irrelevant in these circumstances.