98 1.8 318is help needed with wheels - bvb
Hello

We bought a BMW 318is at christmas. At the time it had 17" wheels but the ride was harsh and bumpy. The suspension has also been lowered unfortunately....

We took it in for an MOT and it failed the lock to lock test and we ended up having to buy some cheap 15" wheels and tires to get it through the MOT. I went to see a BMW specialist yesterday to sell on the 17" alloys and he commented that the current wheels are wrong for the car.

Thats the background, i have a couple of questions really as neither of us know much about cars...

1. What wheels would you recommend? The guy at the specialist tried to sell us another set of 17" alloys. Would these be correct and would it not fail the same test come next MOT? he assured me they would be ok. He also has a set of 15" alloys, or 16".

2. The speedo seems to be out with the current 15" wheels. How easy or costly is this to fix? it seems to be out compared to the satnav speed, with the 17" wheels the speeds matched

3. How expensive would it be to get the suspension put back to normal, ie not lowered. the speed bumps around here are horrendous adn regularily scrap the bottom of the car... The current suspension seems to be less than a year old if that matters

thanks in advance, any help would be hugely appreciated

bvb

Edited by Dynamic Dave on 07/05/2009 at 01:08

98 1.8 BMW 318is help needed with wheels - adverse camber
Why did it fail the mot? Wheels fouling something? Why ? Has the alignment been checked (I mean the whole alignment not just the tracking)


What are the 17" wheels (and tyre size) fitted - and how do they differ from the wheels the specialist is offering? Different offset presumably?

Speedo out? What was the original tyre size and what is the new tyre size?

I thought the 318IS had a lower sports suspension from new (compared to the se or es)? You need to know more about what is installed before you can know what to do next. Is it the original shocks with shorter springs or is it a full replacement package?

Worst case would be a need to replace the entire suspension.

Edited by adverse camber on 06/05/2009 at 19:30

98 1.8 BMW 318is help needed with wheels - jc2
Ask the previous owner-he may still have the bits taken off.
98 1.8 BMW 318is help needed with wheels - bvb
Thanks for the reply adverse camber. To be honest you have completely lost me...

the car failed MOT because the wheels where hitting on the inside arches at full lock. Smaller wheels fixed this problem, it was smaller wheels or a new steering rack. Smaller wheels were a cheaper option.

The 17" wheels were from a 328i as far as i know. I have no idea about how they differ, they look different, they are both 17", do you get them in different widths? this is my first car and i really dont have a clue about anything like this.

According to the book that came with the car the original wheels were 15" but the speedo is definately out now with 15" wheels so i presume its been altered to work correctly with 17" wheels.

I couldnt tell you if the suspension had been lowered or not but the bloke at the garage told me it has been lowered, and in the last year, he said it had been lowered quite a bit. All i know is the car scrapes alot of speed bumps. Thinking about it, im pretty sure he said it was new springs, im sure he said there was new springs that still had grease on them so they werent that old

again, this is the extent of my knowledge, i really know next to nothing about cars...

thanks again
98 1.8 BMW 318is help needed with wheels - bell boy
Sounds like a classic case of a slammed car with the widest rims nailed on possible
Let me tell you why it failed the mot
You are going round a roundabout and change lane as you have to boot it,your wheel will lock up in the arch the car will spin and the next 15 seconds could be life changing
if you want to drive a safe car then take on board the garage that said they have the correct wheels to fit your car,you might also need the springs that put your car back to factory spec
Remember you can sell the old springs and wheels to another person who likes to ride on the floor
98 1.8 BMW 318is help needed with wheels - bathtub tom
Does your insurance company know it's been changed from original spec?

You may well find it's cheaper to put everything back as it should be rather than try and find out what's been done, declaring it to them and paying the extra premium.

If the car's been modified from it's original spec in any way and you don't declare it, they could use it as an excuse not to pay any claim!
98 1.8 BMW 318is help needed with wheels - bvb
thanks again for the replies.

the insurance company does know that the suspension has been lowered and that the wheels are not the originals that come as standard. for my honesty im paying over £500 a year. I think the lowered suspension cost about 120 extra a year and the wheels didnt add too much

I currently have 15" wheels on the car, as soon as i was told about the problem with the car and the wheels i had them changed and sold the 17" wheels.

All i was asking was a recommendation for wheel sizes for the car. It looked better with 17" wheels but when i found out they were dangerous they were changed the same day. I dont know but i presume that the width of the tires was causing the problem, and is it possible to get thinner 17", i think the ones causing a problem were 8.5" wide. i dont know if wheels, tires come as standard widths, are all 17" wheels, tires the same width? If so, are 16" wheels thinner? If push comes to shove i will just get a set of 15" alloys that they have. Its purely for asthetics that im asking, but i also want to be safe.

i also want to add that is my second ever car, im 34 and havent been driving very long. I didnt know when i bought the car that anything had been done to it until a friend told me it had been lowered and the wheels werent the proper ones. if i can afford to get the springs changed to the proper ones i will, scrapping speed bumps isnt fun

Edited by bvb on 06/05/2009 at 21:46

98 1.8 BMW 318is help needed with wheels - bathtub tom
Try this site (others are alo available) to calculate the difference in rolling diameter of different wheel and tyre size combinations - it's not just the wheel diameter that affects the overall size.
98 1.8 BMW 318is help needed with wheels - Dynamic Dave
Try this site


Link?
98 1.8 BMW 318is help needed with wheels - adverse camber
wheels and tyres come in different widths. As Bell Boy says, it sounds yours has been chaved up with silly wide wheels and 'slammed'

Sometimes the correct wheels will foul the arches or suspension due to the lowering (it alters the angles that the wheel is at) but in your case it sounds like the wrong wheels.

The problem arises due to the wheels/tyres being too wide and/or the offset being incorrect (for simplicity you can think that the offset defines how far the wheel protrudes into the wheel arch beyond the car hub)

Changing the wheel size from 15 to 17 should not make the speedo incorrect as long as the correct tyres are fitted. All that should happen is that lower profile tyres are used with larger wheels. However if this isnt done then the reading of the speedo will be wrong. The circumference of the wheel should stay the same so that the distance covered by a single revolution of the wheel is the same regardless of what wheel/tyre combo is used.

In your position I wwould try and get some original fitment wheels and tyres. It is possible that the speedo (or more accuratly the computer that controls it) has been altered, but I would also be worried that you still may have incorrect wheels/tyres fitted.

I'm not a bmw expert, but if you can quote the full tyre sizes ie 205/45-17 from the side of the tyre - front and rear may be different and tell us what your handbook recommends then we can probably tell you what you really need.