How to reduce caster?

[Trackslag172]

Hello,

After fitting BC coilovers and poly bushes all round, the caster of the front wheels has increased by a noticeable amount. Normally this would be a good thing, but not in my case. The car is a track car and unless I raise the suspension up much higher then I would like the wheels rub near the front of the arches under heavy cornering. see pic below
I was going to cut out the metal that it was rubbing on (as I have with all the other problem bits of metal) however the arch looked quite important, so I think I will leave it in.
Can anyone recommend a way to reduce the caster again so the wheels sit closer to the center of the arch?

image posting

Cheers,
Tim

 

[Trackslag172]

Anyone?

 

[NorthloopCup]

What wishbones have you got fitted? If they're cup ones you can fit non cup items instead.
Or you need adjustable top mounts.

 

[Trackslag172]

Standard 172 wishbones, not cup. Are adjustable top mounts interchangeable between brands? I have BC coil overs, but BC don't do adjustable top mounts for the clio 172. Can I fit AST ones?
Cheers

 

[NorthloopCup]

Standard 172 wishbones, not cup. Are adjustable top mounts interchangeable between brands? I have BC coil overs, but BC don't do adjustable top mounts for the clio 172. Can I fit AST ones?
Cheers

Yeah you can fit Ast top mounts mate. I'm trying to figure out how you've got too much castor from fitting coilovers though? Doesn't make sense.

 

[Trackslag172]

I am new to this, so correct me if I am wrong, but I assumed it was the polybushes that have caused the increased caster.
I am trying to find asjustable top mounts, but can only find camber adjustable ones, do AST make caster adjustable ones?
cheers

 

[Dan@SJM]

There's something not right with this/your car if that's created an issue.

 

[Trackslag172]

There's something not right with this/your car if that's created an issue.

Any idea what?
Pics below are of the wishbones while the car was still on the ramp, they are not great, but does anything stand out?
Cheers

image upload without registration

 

[Dan@SJM]

Not from that picture. No. Need a picture of the wishbone from underneath it

 

[Dan@SJM]

Is it just catching the bumper brackets?

 

[Trackslag172]

Is it just catching the bumper brackets?

It was after I lowered it, but I have now cut the bumper brackets out and tried to lower it more but the wheel rubs under heavy cornering. You can see where its rubbing in the first pic, its the smooth whiteish mark at the front of the arch

 

[ed55j]

Got a photo of the wheel in the arch?

 

[Dan@SJM]

Oh, I thought you meant wing! Most of them do that, just beat/trim it

 

[Trackslag172]

Oh, I thought you meant wing! Most of them do that, just beat/trim it

Haha, you had me worried there. I have done that with most things that have got in the way. Can I grind out this part of the arch? its not very thick metal and behind it is the engine bay, am I not at risk of weakening the structure?
Cheers

 

[Trackslag172]

Got a photo of the wheel in the arch?

As requested

LHS

RHS

 

[Dan@SJM]

Haha, you had me worried there. I have done that with most things that have got in the way. Can I grind out this part of the arch? its not very thick metal and behind it is the engine bay, am I not at risk of weakening the structure?
Cheers

Not atall, you can take about 20mm off it in depth and it'll be fine

 

[Trackslag172]

Not atall, you can take about 20mm off it in depth and it'll be fine

Cheers, Ill have a go tomorrow as long as the weather holds out.
Am I right in thinking that caster adjustable top mounts would have little effect on my issue? As I want the bottom of the strut to move back, not the top of the strut to move forward

 

[Dan@SJM]

Yeh pretty much

 

[bozothenutter]

The second picture looks as if the fat part of the bush is on the outside of the wishbone?
Ans where is the metal sleeve in that pic?

 

[STEVE.M]

It was after I lowered it, but I have now cut the bumper brackets out and tried to lower it more but the wheel rubs under heavy cornering. You can see where its rubbing in the first pic, its the smooth whiteish mark at the front of the arch

I put a spacer between the top mount bearing and the shock assembly,so that the bump stop comes into play before the tyre hits the arch.
With the BC,can`t you wind more pretension on the spring,and then drop the cartridge lower into the hub clamp?

 

[STEVE.M]

As requested

LHS

RHS

Just saw these,that`s rally cross ride height.
Increase the spring pretension and lower the cartridge into the clamp.

 

[Trackslag172]

I put a spacer between the top mount bearing and the shock assembly,so that the bump stop comes into play before the tyre hits the arch.
With the BC,can`t you wind more pretension on the spring,and then drop the cartridge lower into the hub clamp?

Just saw these,that`s rally cross ride height.
Increase the spring pretension and lower the cartridge into the clamp.

I have it raised up high atm as its also used on the road, it gets lowered more for the track. I haven't played with the spring pretension since yet (still learning) I'll have a play tomorrow and increase it.
Cheers for the advice

 

[Trackslag172]

The second picture looks as if the fat part of the bush is on the outside of the wishbone?
Ans where is the metal sleeve in that pic?

+1 to this man. After i read the comment it got me thinking, so i have now had a chance to check the fitting of the poly bushes and he is right. The rear polybush on each wishbone is fotted the wrong way round, which has increased the caster.. I will update the thread when i have swapped it.
Cheers

 

[bozothenutter]

Well you did find a way to increase caster!

 

[TheEvilGiraffe]

Haha you wally..

Sorted it ?

Had no issues with my BCs. They are superb on road and track !

 

[ripp]

One year later lol.. As above, have you sorted it mate?
I have the EXACT same problem with mine, it's lowered about the same as yours but I have the original wishbone bushes and it still rubs in the exact spot!. It looks quite like yours with the wheel moved towards the front of the car. I thought well it's because 182's have increased wheel base and they only moved the front but I've seen many 182's here and the wheels were sitting bang on in the center!

 

[Trackslag172]

Yes mate, it's all fixed and it was the polybushes the wrong way round as bozo said.

Even once it was fixed it still rubbed a bit so i cut out more metal until it stopped rubbing.
I ended up cutting out the entire bracket where the front bumper screws too, i'll see if i can find a pic

25mm spacers might help as well depending on where its rubbing and stiffening the suspension will help

 

[ripp]

yeah but I have the std bushes on the lower arms so nothing to correct there like you did. Fitting spacers would make it worse because while turned the wheel will have a slightly left-forward position and could rub even harder.
I've seen that you have got rid of the lower part of the arch liner which I'd like to keep really, and this would mean that I'll have to cut more metal and also make a hole in the arch liner aswell, then cover the hole with something looking like a turtle back shell, I'm already having a headake lol! fortunatelly mine touches only in downhill hairpins (ie on mountain roads). On the race track I had no issues so far.
Annoying still that renault couldn't make a car with the wheels centered in the arch!