Re: I think I may have gone over the top.

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Peter Hill 22 years ago

>>
>> > Fitted some "new" alloys today, as you do gone from the standard 13" >> wheels up
>> > to 14" (woohoo I'll be after a max power feature with that ;) ) only >> slight
>> > problem it I'm going to have to start going to the gym as the steering is >> so
>> > much heavier & to think they are only two and a half inches wider than >> stock. I
>> > guess I've spent way to much time on German and Netherlandic web sites not >> to
>> > mention ebay.
>> >
>>
>> Man, you crazy! I went up from 155 to 185 on my old Peugeot 305 GR (yeah,
>> and the amount I paid was as mental as the actual idea of doing it in the
>> first place) - I didn't really notice much difference in the weight of the
>> steering, just that it understeered less, but I guess that's only about half
>> the difference you've made - what size tyres are you on now?
>
>14x8s with stretched 195/45s for the euro look and the fact they are 1/2 the
>price of 225/40s.

By fitting them to a rim 2" too wide for a 195 they are effectively

215. Rule of thumb is add 5mm per 1/2inch. Must have the rim very exposed. Either learn to drive and park very carefully or have banged up and duff looking rims in no time at all. Did they get the offset right? Or has the wheel had to be offset outwards to clear springs etc. An increase in scrub radius will make the steering a lot more heavy. If you have front / rear split brakes it will be OK just wear wheel bearings and other suspension parts out quicker due to acting like a longer lever arm. If you have diagonally split brakes and positive scrub radius it could be lethal as in the event of a brake failure on one circuit it will pull very hard towards the one working front brake. With negative scrub radius the braking tends to pull towards the braked wheel and the steering pulls away so they tend to balance out. Start looking for a power steering rack and pump from an up-market model in the breakers yards.

You won't see any competitive race cars with this sort of thing. All show, no go.

-- Peter Hill Spamtrap reply domain as per NNTP-Posting-Host in header Can of worms - what every fisherman wants. Can of worms - what every PC owner gets!

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Depresion 22 years ago

Good news, already have power steering with it being the top of the line model I could be wrong but I do think it also has some form of breaks but haven't got round to taking my foot of the right pedal (hence big grin every where I go) as for the offset who knows? One of the disadvantages of getting wheels 2nd hand and cheap along with the fact there are a few small scrapes on the rim (having been fitted with 185s previously) though I can say there isn't any way they would sit further in at the front without catching on the callipers (there goes the big break upgrade).

Still they look nice and wide on the car, just the look I was after:

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white one closest to the camera)

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Depresion 22 years ago

So working from the 175's on the stock 5.5J rims:

5.5 = 175 6.0 = 180 6.5 = 185 7.0 = 190 7.5 = 195 8.0 = 200

So did VW fit the wrong tyres as standard or am I only 5mm too thin? If you add

25mm per inch (about right) then you end up with 225s on 7.5j but adding 20 per inch you end up with 225's for the 8s (even then it's only an inch and a half between the 195's and 225s). There is something very odd about the way we calculate rubber sizes.

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Depresion 22 years ago

Oh your not the Mossimo/Greg Murphy Racing Peter Hill are you?

(You know I should consolidate all my thoughts then only need to post once. ;)

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Chris B 22 years ago

Man, you are crazy! Figure out that offset, you should be able to measure it if you take it off and work out if it's right for your car. Unnecessary wear is just... unnecessary! And why not chuck on some tyres the right size? OK, I guess it was the look you were going for but I have to admit I don't really get it?!

Think of that extra grip you could have!

Chris.

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Depresion 22 years ago

Guilty as charged.

Considering what they came off and the fact they don't scrub the offset will be between 20-30 right in line with what I need. You don't think I would really fit wheels without knowing the offset is right do you? (well not after the problems with the BMW (If I can remember who it was that told me E21 and E30 3 series have the same offset I'll ask him to try fitting the wheels)).

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Nom 22 years ago

That's not right, cos you really need 225 tyres on an 8" rim.

It's usual practice to put 205s on a 7" rim, and 215s on a 7.5" rim too.

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Depresion 22 years ago

That's what I was thinking following Peters Rule of thumb.

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Peter Hill 22 years ago

No I was giving you the effective tread width due to stretching.

185/195's normally go on 6 inch rims. If you put a 195 on a 6.5 inch rim it will have a 200mm tread, 7 inch rim 205mm. 7.5 inch 210mm, 8 inch 215mm. 175's go on 5.5inch rims but when finding the effective tread width you work from the stock rim for the tyre not the car.

Re-reading your post I see it's a low profile 195/45 which needs a wider 6.5 inch rim. So on a 8 inch rim it's effective tread is 210mm, that's only about 7mm wider than the rim seat giving nill buffer on a kerb as the rim has flanges which will be exposed, on a stock 6.5 rim the tread would be 30mm wider than the rim giving maybe 5-10mm tyre buffer for the rim flanges.

Nom has told you what sizes fit 7, 7.5 and 8 inch rims at the low profile you are using. If a 195/45 has the correct rolling diameter you will be down to /40. What was the stock 175/xx 14 tyre profile?

-- Peter Hill Spamtrap reply domain as per NNTP-Posting-Host in header Can of worms - what every fisherman wants. Can of worms - what every PC owner gets!

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Re: I think I may have gone over the top.

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