Help!! Suspension isn't even.

Looking for some urgent help if possible, my car is on stilts lol. As you can guess from my numerous threads i'm getting my car into tip top condition for the summer. I want to get every little crease ironed out and i've came accross a big one.

Today i went out to lift my suspension by 10mm as when i set the hight it settled down a little low. I thought i would go round all 4 corners and check every one to make sure they were all the same. When i came to the front i noticed the difference in height, to have them even, is 10mm. I can't for the life of me figure out why. I have checked loads of dimensions, with and without load and i'm still none the wiser. I've taken some pics to explain....

Any ideas? Its definitely not the shocks thats causing the height difference as even without any load there is a difference.

Thanks

Just checked from the top of the shock to the bottom and they are both exactly the same so its something else causing the difference.

could the preload be out ?

could the preload be out ?

I thought about that, but if it was there would be a difference in the length of the spring once load was on it, there isn't though.

Regardless of whether there is load on the shocks or not the overall length of them are the same at either side eg. when no load 20" when load is on them 19" on each side. As far as the shocks and springs are concerned every dimension matches on both sides with or without load. Its as if the hub on one side is 0.5" higher.

Could the frame be bent?

Or any of the bushes worn out?

Could the frame be bent?

Or any of the bushes worn out?

Could be bushes, i don't think its the frame as i've measured everything i can think of. I'm going nuts with the tape measure trying to find what it can be.

Think i've found the problem....

Would i be right in saying that lower wishbone is bent just before the hub? I've taken pics of both sides for comparison.

Hmm, looking at them again i can't make up my mind.

I would have a word with Chris Wilson. Those coilover units can be tricky to set. You need to get the ride height set and then set the corner weights. Not something you can do without the right equipment.

I would have a word with Chris Wilson. Those coilover units can be tricky to set. You need to get the ride height set and then set the corner weights. Not something you can do without the right equipment.

Yeah i'll be taking it to somewhere for the proper alignment etc. The ride height should be straight forward to do as i have done it before, but its really throwing me. I've got the other 3 corners spot on without any hassle.

The only thing i am left with now is to have the coilover on the right hand side set further out than the other.

You don't want to worry about setting all the units so they measure the same, you want to set them so the car sits at the right height. Corner weight adjustment will then ensure that the weights on the left wheels match those on the right. An ordinary wheel alignment place might not have the faintest idea what you're on about if you say "corner weights". A good performance car specialist, particular if they do race or track cars is where you want to look.

You don't want to worry about setting all the units so they measure the same, you want to set them so the car sits at the right height. Corner weight adjustment will then ensure that the weights on the left wheels match those on the right. An ordinary wheel alignment place might not have the faintest idea what you're on about if you say "corner weights". A good performance car specialist, particular if they do race or track cars is where you want to look.

Ahh ok, thats not a problem.

Is 10mm not a fair bit out though?

Have you checked the measurement under the car from the ground to the chassis/crossmembers at each corner? It's also important to have very level ground. If you're not sure if the ground is absolutely flat and level, measure the ride heights then turn the car round (exactly the same spot) and measure again. If the apparent error moves or changes, the ground isn't level. If the ground is level and you can adjust the the coilovers to get the car to sit where you want it at all four corners that's a start. Completely ignore measurements on the coilovers because your springs might not be a perfectly matched set. That's why coilovers are so good - you can adjust to compenmsate for things like spring mismatch. In an ideal world you should have all your springs checked for free length and rate (kg/cm). If you can get all four corners (under the car) level and then can't get corner weights to match side to side, you may have a slight twist in the car - unlikely! Corner weights only really need to be measured at the front wheels because the back will be right if the front is.

If your front wheels lock (or attempt to lock) under heavy braking at the same time left/right, your corner weights are OK.

If I didn't live 2000km away I'd offer to help. Many years of setting up race cars taught me to ignore measurements on coilovers other than as a starting reference.

Have you checked the measurement under the car from the ground to the chassis/crossmembers at each corner? It's also important to have very level ground. If you're not sure if the ground is absolutely flat and level, measure the ride heights then turn the car round (exactly the same spot) and measure again. If the apparent error moves or changes, the ground isn't level. If the ground is level and you can adjust the the coilovers to get the car to sit where you want it at all four corners that's a start. Completely ignore measurements on the coilovers because your springs might not be a perfectly matched set. That's why coilovers are so good - you can adjust to compenmsate for things like spring mismatch. In an ideal world you should have all your springs checked for free length and rate (kg/cm). If you can get all four corners (under the car) level and then can't get corner weights to match side to side, you may have a slight twist in the car - unlikely! Corner weights only really need to be measured at the front wheels because the back will be right if the front is.

 

If your front wheels lock (or attempt to lock) under heavy braking at the same time left/right, your corner weights are OK.

 

If I didn't live 2000km away I'd offer to help. Many years of setting up race cars taught me to ignore measurements on coilovers other than as a starting reference.

Superb buddy thanks for the info. I'm working in my garage which has a concrete base. Its pretty level thankfully

Bumpski