Fitting wider wires and tyres?

[boggie]

Hi All,

 

I am planning on fitting a set of wires from a TR4, shod with 185/70/15 tyres, to my TR3a. I have been reliably informed (thanks Paul) that I need to modify the return edge of the rear arches but the fronts will be just fine. I know that the wheels will not fit in the spare wheel bay but I will retain one of the original wires as a spare.

 

Has anyone done this mod to the rear arches and able to offer any advice? How much of the return edge needs modifying, by how much and what is the safest way to do it without deforming the outer wing?

 

Many thanks, Ian

[vivdownunder]

Eh ?

 

Ian, hope you realise TR4 wheels were the same 4.5" rim size as 3A's, but uprated during production from 48 to 60 spokers.

 

For a 185 size tyre you'll need the optional wider TR6 72 spoke x 5.5" wires.

 

Trial fit the left rear wheel first, as many cars had bodies offset to the chassis, and if you've got one of these, there's about 1" less wheel space on that side of the car.

 

The proper way to modify the stiffening flange on the rear wheel arches is to have them rolled around wire like the front wheel arches, if indeed you can find a beater with the skill. Then both guards will need respraying, so it ends up a bucket load.

 

Regards,

 

Viv.

[boggie]

Eh ?

 

Ian, hope you realise TR4 wheels were the same 4.5" rim size as 3A's, but uprated during production from 48 to 60 spokers.

 

For a 185 size tyre you'll need the optional wider TR6 72 spoke x 5.5" wires.

 

Trial fit the left rear wheel first, as many cars had bodies offset to the chassis, and if you've got one of these, there's about 1" less wheel space on that side of the car.

 

The proper way to modify the stiffening flange on the rear wheel arches is to have them rolled around wire like the front wheel arches, if indeed you can find a beater with the skill. Then both guards will need respraying, so it ends up a bucket load.

 

Regards,

 

Viv.

[boggie]

Eh ?

 

Ian, hope you realise TR4 wheels were the same 4.5" rim size as 3A's, but uprated during production from 48 to 60 spokers.

 

For a 185 size tyre you'll need the optional wider TR6 72 spoke x 5.5" wires.

 

Trial fit the left rear wheel first, as many cars had bodies offset to the chassis, and if you've got one of these, there's about 1" less wheel space on that side of the car.

 

The proper way to modify the stiffening flange on the rear wheel arches is to have them rolled around wire like the front wheel arches, if indeed you can find a beater with the skill. Then both guards will need respraying, so it ends up a bucket load.

 

Regards,

 

Viv.

 

Hi Viv,

 

They are 72 spoke wheels. From what you are saying it sounds like they are not original TR4 items, perhaps the owner fitted TR6 wheels? It seems you are saying that I will not be able to fit these wheels to my car without extensive modification. I was hoping simply to put a flat, heavy steel block on the outside of the arch then carefully fold the stiffening flange up with a hammer.

 

Thanks, Ian

Edited January 7, 2009 by boggie

[vivdownunder]

Ian, there's plenty of TR3A's around with 72 spoke 5.5" rim wire wheels, but there can be challenges fitting them.

 

If you use the block against the rear wheel arch method, then don't fully tap the flange back tight against the mudguard. Work along back and forth very slowly so you don't risk splitting the flange. By leaving the flange as a V shape, you retain some rigidity in the guard.

 

Good rear springs with no sag are important with the wider wheels, as you strike trouble when the car is loaded up for a trip with a full tank of fuel.

 

Last year a mate fitted a new set of chromed Dayton 72 spoked wheels to his 3A, and he just pulled the rear guards out a bit around the wheel arches so the tyres cleared when cornering, and you don't even notice the slight mis-shape. See http://www.tr-register.com.au/files/brownk.htm

 

Regards,

 

Viv.

[david ferry]

Ian,

 

Picture this.....

 

You are away touring and get a puncture which means you need to change the wheel.

 

You take the smaller spare out, jack up the car, remove the 5.5" wheel and fit the narrower spare. Everything is OK so far. I am not too sure what the law says about maximum speed with 1 narrower wheel but I know that with a space saver spare fitted to the car you are limited to a lower top speed. Does this apply here?

 

You lower the car off the jack and replace the spare wheel cover. The 5.5" wheel you removed won't fit in there whatever you try to do.

 

The decision then needs to be made as to what to do next.

 

The real problem is that you are miles from anywhere, or it is late at night. You may even be heading home.

 

Where does the wheel with the puncture go?

 

It won't fit in the boot, you could leave 'Mrs Ian' at the side of the road, to be able to get the wheel into the passenger side of the car but this isn't really a good idea (or so you are told!). In any event as I have never tried to do this with mine, I am not sure if it will fit. It may go behind the seats but may make a bit of a mess. In my TR3a, this would be impossible due to the roll bar.

 

The only option is to leave the wheel at the side of the road and go back later to collect it, get it repaired, put it back on the car and put the spare back in it's home under the boot.

 

What if there are no local garages with equipment to balance the wheel after repairing the tyre?

 

Bit of a bugger if this happens a significant distance away from home which is where you may now be headed!

 

What's the solution?

 

If you are fitting wider wheels (I have 72 spoke 5.5" wires on my TR3a) you need to wire the rear wings as described by Viv but you must also modify the car so that you can house a knackered 5.5" wheel.

 

The solution in my case was to remove the boot floor, creating a flange that can be folded down into, and welded to, the old spare wheel space. This has been very well done and looks like it was always like this (unless you have a sidescreen car and know that this was not the case). I then have a false boot floor to go over the spare wheel so that the boot can be used as normal. This is also very well done.

 

All of this means that I can then have a 5.5" spare wheel along with the 5.5" wheels on the car. If I get a puncture, changing the wheel does not create the difficulty outlined above. A side effect of this is that I can store tools and spares inside and around the spare wheel really easily.

 

Before any originality freaks blow a fuse, all of this is easily reversible and the boot floor was very badly dented anyway.

 

None of it is particularly straightforward and I would suggest that you give serious consideration to the problem of storing the knackered wheel before you proceed further.

 

Good luck

 

Regards

 

David

[Tr4Tony]

Nice solution David !

 

Or you could run one on the bootlid.

[unclepete]

Or stick it in the boot and leave it open!

 

Run KN Minilite lookalike knock offs on mine with 185/70 Vredenstein Sprint Classics and all fits fine with the inner rear wings rolled up.

 

Keep an old 155 tyre on a 48 spoke wire wheel as a spare along with about half the tools and spares known to man!

Really handy that spare wheel box!!

 

Unc

[pfenlon]

Hello Boggie my 72 spoke chrome wheels are OK when the rear wings were rolled. My pal did mine using galvanised 4mm wire, he rolled the edges around the wire, the rear wings are now much stronger too. Done before painting though

 

David must have had lots of punctures poor lad, and well, his cup is more than half empty tonight.

 

I have to reluctantly admit I have an old 10 spoke wire in the slot at the back for the dreaded day I do puncture, and never gave a thought to what to do with the punctured wheel.

 

And guess what I really dont give a shi_e.

[boggie]

Hello Boggie my 72 spoke chrome wheels are OK when the rear wings were rolled. My pal did mine using galvanised 4mm wire, he rolled the edges around the wire, the rear wings are now much stronger too. Done before painting though

 

David must have had lots of punctures poor lad, and well, his cup is more than half empty tonight.

 

I have to reluctantly admit I have an old 10 spoke wire in the slot at the back for the dreaded day I do puncture, and never gave a thought to what to do with the punctured wheel.

 

And guess what I really dont give a shi_e.

 

 

That is what I was planning too!

 

However, I am a little concerned about rolling the rear wings. I have sourced some 4mm stainless steel, marine grade rope but bashing away at a 50 year old steel flangs is scary. Also won't the rolled up edge collect dirt and moisture?

 

Cheers, Ian

[BrianC]

I am a little concerned about rolling the rear wings. I have sourced some 4mm stainless steel, marine grade rope but bashing away at a 50 year old steel flangs is scary. Also won't the rolled up edge collect dirt and moisture?

I would also be worried about doing this myself as I don't have the skills but would entrust it to a professional. Apart from the extra clearance, it should provide a much stronger wheelarch. The 90-degree folded edges are prone to splitting on the standard rear wings, whilst the rolled/wired edges on the front wing have never been a problem (although the bottom and rear sections are another story ).

 

Since you probably already have rolled edges at the front, why worry? Just make sure the rolled edges are well protected with Waxoyl or similar - inside and out.

Edited January 15, 2009 by BrianC

[stuart]

 

That is what I was planning too!

 

However, I am a little concerned about rolling the rear wings. I have sourced some 4mm stainless steel, marine grade rope but bashing away at a 50 year old steel flangs is scary. Also won't the rolled up edge collect dirt and moisture?

 

Cheers, Ian

Ian rope is no good as it wont give you the strength of a solid piece of wire. When rolled ensure that the inner lip is well sealed off and you shouldnt get any rot problems and as has been already noted it makes for a much stronger arch.

Stuart.

[Badfrog]

Hi Stuart,

 

Just don't. You'll increase the shearing forces on the chassis, loose max speed and gas mileage, all for no real benefit except getting the famous East-LA look.

 

Keep your 4.5 x 15 rims, use Vredestein tyres 165x15x80 (check the noisiness of the last model, you might want to stick to the older type) or Michelin XAs 175, and use the savings for hi-speed driving lessons on a circuit.

 

Cheers,

Edited January 16, 2009 by Badfrog

[MCOOPER53]

Hi All,

 

I am planning on fitting a set of wires from a TR4, shod with 185/70/15 tyres, to my TR3a. I have been reliably informed (thanks Paul) that I need to modify the return edge of the rear arches but the fronts will be just fine. I know that the wheels will not fit in the spare wheel bay but I will retain one of the original wires as a spare.

 

Has anyone done this mod to the rear arches and able to offer any advice? How much of the return edge needs modifying, by how much and what is the safest way to do it without deforming the outer wing?

 

Many thanks, Ian

 

I have 195/65/15 tyres fitted to my 3A on 72 spoke wires. After a few months of driving I noted where the rear tyres were rubing on the rear wheelarchs, I then ground down the flange on the wing with an anglegrinder to suit. You may find, like I did that it's only the top part of the rear wheelarch that is a problem.

 

Regards

[boggie]

Excellent! Thanks for that. It is encouraging to hear from someone else with first hand experience, especially as your tyres are even wider. Of course tyre type also has some affect, I have a Lotus seven type car on which the tyres were close but cleared the rear arches until I fitted new Pirelli rubber. Now they rub.

 

What tyres are you using?

[MCOOPER53]

Excellent! Thanks for that. It is encouraging to hear from someone else with first hand experience, especially as your tyres are even wider. Of course tyre type also has some affect, I have a Lotus seven type car on which the tyres were close but cleared the rear arches until I fitted new Pirelli rubber. Now they rub.

 

What tyres are you using?

 

I've used a few different types over the years, Yokohama A008R 195/60 15, Pirelli P6000 195/65 15 and at the moment I have Dunlop SP9 195/65 15. All fit no trouble.