BC Racing Colivers for 240z

SeanDezart

Well-Known Forum User
I've got people here who want to remove them - way too hard and regret having butchered their legs to fit them.
 

richiep

Club Member
Surely you can change the springs though to address the hardness issue? I think in the US at least you can order them with whatever spring rate you want (or just go with the default 4/5kg setup).
 

strugrat

Club Member
Surely you can change the springs though to address the hardness issue? I think in the US at least you can order them with whatever spring rate you want (or just go with the default 4/5kg setup).

Yep easy to change springs and the shocks are rebuildable so you can adjust the damping as well if you send them off to someone in the know.
 

johnymd

Club Member
I thought I’d add to this existing thread for anyone that search google on this suspension change.

I have a couple of Zed’s on BC’s and I’m generally happy with them. They also do improve with use so don’t judge until you’ve put at least a few hundred miles on them. Make sure your lower arms move freely with as little resistance as possible as this will have a very big impact on ride quality. You can only then judge the ride quality of the BC’s.

The main issue I have is with regard to the amount of height adjustment. With the strut cut to leave 50mm of tube you cannot get the car that low. I would probably leave a little less tube sticking out. Especially on the back. Or just go the the extreme low which have the ability to drop your car another 1”. The standard are listed at 1”-3” drop and the extreme 2”-4”. Here is a picture of my zed with the standard BC’s at their lowest ride height. I could lower it further by removing some pre load but didn’t want to go that route.

The picture is with 16x8 0et wheels/205/55r16 tyres.
 

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Turn & Burn

Club Member
I thought I’d add to this existing thread for anyone that search google on this suspension change.

I have a couple of Zed’s on BC’s and I’m generally happy with them. They also do improve with use so don’t judge until you’ve put at least a few hundred miles on them. Make sure your lower arms move freely with as little resistance as possible as this will have a very big impact on ride quality. You can only then judge the ride quality of the BC’s.

The main issue I have is with regard to the amount of height adjustment. With the strut cut to leave 50mm of tube you cannot get the car that low. I would probably leave a little less tube sticking out. Especially on the back. Or just go the the extreme low which have the ability to drop your car another 1”. The standard are listed at 1”-3” drop and the extreme 2”-4”. Here is a picture of my zed with the standard BC’s at their lowest ride height. I could lower it further by removing some pre load but didn’t want to go that route.

The picture is with 16x8 0et wheels/205/55r16 tyres.

Good feedback!
I think it looks great at that height, I’d be happy with that. I’ve been warned off going too low as the floor rails catch all the time.
 

johnymd

Club Member
Had a little play with my BC top mount today. They are the standard 3 bolt adjustable BC items. These can be adjusted by lowering the strut slightly and still leaving a tiny bit of the bolts engaged in the car. There is then just room to get to the Allen bolts with a ball end Allen key. Out of the box the BC’s have the Allen bolts furred so you can’t increase the camber, only decrease it. Which seams a bit odd to me. To allow increased camber you will need to remove removethe 2 inner Allen bolts and install them on the other side of the outer bolts. This will allow you to then increase the camber a bit to where the damper adjust nearly touches the inner side of the hole in the turret. Hope this make sense.

Here’s the car lowered to its maximum and with 205/50r16 tyres fitted.
 

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WazzaJB

Club Member
I've
I thought I’d add to this existing thread for anyone that search google on this suspension change.

I have a couple of Zed’s on BC’s and I’m generally happy with them. They also do improve with use so don’t judge until you’ve put at least a few hundred miles on them. Make sure your lower arms move freely with as little resistance as possible as this will have a very big impact on ride quality. You can only then judge the ride quality of the BC’s.

The main issue I have is with regard to the amount of height adjustment. With the strut cut to leave 50mm of tube you cannot get the car that low. I would probably leave a little less tube sticking out. Especially on the back. Or just go the the extreme low which have the ability to drop your car another 1”. The standard are listed at 1”-3” drop and the extreme 2”-4”. Here is a picture of my zed with the standard BC’s at their lowest ride height. I could lower it further by removing some pre load but didn’t want to go that route.

The picture is with 16x8 0et wheels/205/55r16 tyres.

I've had some BCs delivered for my 280z, haven't fitted them yet. I've got low profile 15" wheels going on.

I'm thinking I should have gone for the extreme low option. Don't suppose you know where the key difference is? You mention about leaving the tube sticking out 50mm? I have a welder doing the work as I'm still fairly useless so keen to ensure I get the height I want.

Thanks
 

johnymd

Club Member
Paul - no, same height.

When I do another set I will probably only leave 40mm of tube left. Make sure they are cut accurate as this will limit the maximum drop for each strut and you would want them the same. The difference is the length of damper body and therefore travel.
 

Turn & Burn

Club Member
Paul - no, same height.

When I do another set I will probably only leave 40mm of tube left. Make sure they are cut accurate as this will limit the maximum drop for each strut and you would want them the same. The difference is the length of damper body and therefore travel.

John, on the BCs the shaft sleeves over the 50mm section where you cut and rests on the forging at the base of the 50mm stub. I don’t think u can gain anything by shortening the stub?
 

moggy240

Insurance Valuations Officer
Staff member
Club Member
John, on the BCs the shaft sleeves over the 50mm section where you cut and rests on the forging at the base of the 50mm stub. I don’t think u can gain anything by shortening the stub?
That's what I thought aswell as on my bc's the thread does not go all the way down so you would not gain anything by doing them shorter. Might be different if you have the extra low kit.
 

johnymd

Club Member
The stub in the bottom prevents the body from being screwed down any further.......I think. I think the sleeve is threaded all the way. So when you wind the body down into the sleeve it will stop when it hits the stub so if you shorten the stub then the body will thread down further. I have some spare sleeves so I’ll check the thread length tomorrow.
 

moggy240

Insurance Valuations Officer
Staff member
Club Member
I can't remember but it did not go all the way to the end. Next time someone gets some it would be interesting to see how far it does go. I know mine are almost to the bottom of the threaded section.i remember thinking I thought it would have been threaded further down when I fitted mine.
 

johnymd

Club Member
Ok. I guess I just assumed they went all the way down without really thinking about it. I’ll check the sleeves I have at the workshop.
 
with the 'extreme' low kit I'd bet you end up with dampers that have a super short stroke/working stroke and suspension thats only useful for taking pics?
 

Turn & Burn

Club Member
Ok. I guess I just assumed they went all the way down without really thinking about it. I’ll check the sleeves I have at the workshop.
Thread stops well short but below this the bore is at least as big as the thread OD. I think what John says is right, they wind down until you hit the stub. On mine this is 150mm down from the top flange (cut at 45mm stub length). The threaded portion on the BC shock shaft is about 180mm long from base to sleeve locking collar.
 

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johnymd

Club Member
I guess the odds are I had to be right at some point in time :)

The stoke listed by BC is smaller (obviously) but not by that much.
 

moggy240

Insurance Valuations Officer
Staff member
Club Member
Maybe I was wrong then, might see if mine will go lower then.
 
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