15" RIMS

[VOLVO 340 (84)]

HELLO I HAVE A 340 84 I JUST WANNA TO KNOW IF I COULD PUT ON 15" RIMS AND DID IT WILL HARM ANYTHING IN THE CAR ?

ALSO CAN I INSTALL S40 STEERING WHEEL ON IT


THNX INADVANCE

[pettaw]

Hello and welcome to V3m, yeah you can install 15" rims no problems, but you have to be careful to get the tyre size right or you'll have problems with the speedo being accurate (although from what I heard about the driving in Egypt that won't matter ) I'd go for 195/50/15. Can't remember what the offset of the rims should be either, but someone else should know!

The steering wheel from an S40 I'm fairly sure won't fit, but tbh you don't know till you try

Hope that helps.

[VOLVO 340 (84)]

thnx very much (have u been to egypt before)

[pettaw]

No, but I used to know someone from Egypt We've lost touch now but he did mention the driving over there being a bit special.

[classicswede]

15" rims will fit no problems.
You need an et of between 35 and 40mm to give the correct ofset.
I would also recomend 195/50/15 to give correct clearance.

[VOLVO 340 (84)]

what u mean by et

and another question if i put 195/50 /15 the speed will not be wrong

[redline]

PCD/Offset Calculations
Most wheels in use today for passenger car purposes have a positive offset. Most 4 x 4 vehicle have zero or negative offsets. Just because a wheel from one vehicle has the same PCD and offset as the wheel from another does not mean they are interchangeable - the centre bore of the wheel and hub must also be the same to ensure centralisation of the wheel, and the shape of the spokes must ensure clearance of the brake calipers. Many manufacturers use the same wheel fitments as others, but some are unique







hope this helps

[VOLVO 340 (84)]

thnx for this great explanation but iam sorry i just want to understand another thing why the speedo reads wrong when changing the rims and the tires and how can i solve this problem

thnx again inadnvance

[redline]

its all about how long it takes the tyre to go around one revolution

The thicker the sidewall (profile)of the tyre the bigger the circumference so the wheel takes slightly longer to do one revolution and this can throw out the gearing of the speedo ,

this can be compensated by fitting low profile tyres and therefore reducing the circumference of the rolling circunference

[redline]

This might help

Point to note: 1 inch = 25.4mm. You need to know that because tyre/wheel manufacturers insist on mixing mm and inches in their ratings.
Also note that a certain amount of artistic licence is required when calculating these values. The tyre's rolling radius will change the instant you put load on it, and calculating values to fractions of a millimetre just isn't worth it - tyre tread wear will more than see off that sort of accuracy.

Lets take an average example: a car with factory fitted 6x14 wheels and 185/65 R14's on them.

Radius of wheel = 7 inches (half the diameter) = 177.8mm
Section height = 65% of 185mm = 120.25mm
So the rolling radius for this car to maintain is 177.8+120.25=298.05mm

With me so far? Good.

Now lets assume I want 15 inch rims which are slightly wider to give me that nice fat look. I'm after a set of 7x15's

First we need to determine the ideal width of tyre for my new wider wheels. 7 inches = 177.8mm. The closest standard tyre width to that is actually 205mm so that's what we'll use. (remember the tyre width is larger than the width of the bead fitting.)

Radius of wheel = 7.5 inches (half of 15) = 190.5mm
We know that the overall rolling radius must be as close to 298.05mm as possible
So the section height must be 298.05mm-190.5mm = 107.55mm
Figure out what percentage of 205mm is 107.55mm. In this case it's 52.5%
So combine the figures - the new tyre must be 205/50 R15
....giving a new rolling radius of 293mm - more than close enough.


A Speedometer error means an odometer error too.
It stands to reason that if you change the rolling radius of your wheels and tyres, and the speedometer no longer reads correctly, that your odometer will also gradually become inaccurate. Assume for example that you bought a car brand new and changed the wheels and tyres on day one from 195.65R14 to 205/50R15 - not an uncommon change. By the calculator above, that makes your speedometer over read by 1.7%. Consequently, the registered odometer reading will also be out by the same value. So for example, when you get to 10,000km of driving (in the real world), your odometer will actually read 10,170km. OK so that's not a huge difference but it is one of the reasons why most car dealers have a disclaimer on their secondhand vehicles telling you that they won't guarantee the displayed mileage. ("Clocking" the odometer is the other reason). Odometer errors due to mis-matched tyres and wheels will happen on regular odometers as well as the newer digital ones.



if you go to


http://www.chris-longhurst.com/carbible ... bible.html


there is a calculator you can use to check you are fitting the right tyres

scroll down the page to
"a tyre size calculator "

[VOLVO 340 (84)]

really i donot know what to say but really thnx very much i used the calculator and i found that i can go on 15" and the speedo will increase by 0.1 only that's great thank u all again really it's a great site

[foggyjames]

As long as you fit 185/55 or 195/50 tyres, there should be almost no change at all.

cheers

James

[VOLVO 340 (84)]

THNX AGAIN

[mickt]

Would this set of alloys fit our cars

http://cgi.ebay.co.uk/Volvo-340-360-440 ... dZViewItem

I would be interested 24hrs left however

mickt

[SteveP]

Yes Mick, they'll fit fine - quite a popular and cheap upgrade