You'd hope so Gary but mine passed it's MOT a few months and less than 2k miles before this thread started so the bushes couldn't have been in much better shape than when you got to see them...
#ZedShed Project Dino D
- Thread starter GazHyde
- Start date
Started the job today @Dino D, I have a few other things that I'm going to change at the same time so hopefull back together in a week or so.
How are you finding the 6kg springs?
I'm finding them very good and got a few more miles done in wet and dry weather to test them out.
Running around 15-17 clicks from soft on the rear and 2 clicks less on the fronts.
I've extended the shocks at the rear fully and raised the rear slightly but I am still getting what I think is bottoming out on sharp bumps like recessed manhole covers and missing chunks of Tarmac (plenty of that here...).
Not entirely sure if it's bottoming out or is it the hard nylon shock bolt bush transmitting more noise or the new top mounts are just harsher than the Meyle ones in there before. It could also be that it needs a spring pad on top too. Some useful threads over on M3 cutters about the BC's and some on there say the shocks should be wound in and on their shortest setting to prevent bottoming out...you might find this useful when doing yours although it is M3 specific but similar setup to ours: http://forums.m3cutters.co.uk/archive/index.php/t-109631.html
Not sure if it's the spring rate but will have it all looked at by suspension guys when it goes in for corner weighting. They are MX5 specialists so should have seen plenty BC's by now. Hopefully in the next week or two depending on schedules.
Running around 15-17 clicks from soft on the rear and 2 clicks less on the fronts.
I've extended the shocks at the rear fully and raised the rear slightly but I am still getting what I think is bottoming out on sharp bumps like recessed manhole covers and missing chunks of Tarmac (plenty of that here...).
Not entirely sure if it's bottoming out or is it the hard nylon shock bolt bush transmitting more noise or the new top mounts are just harsher than the Meyle ones in there before. It could also be that it needs a spring pad on top too. Some useful threads over on M3 cutters about the BC's and some on there say the shocks should be wound in and on their shortest setting to prevent bottoming out...you might find this useful when doing yours although it is M3 specific but similar setup to ours: http://forums.m3cutters.co.uk/archive/index.php/t-109631.html
Not sure if it's the spring rate but will have it all looked at by suspension guys when it goes in for corner weighting. They are MX5 specialists so should have seen plenty BC's by now. Hopefully in the next week or two depending on schedules.
Little update...
So had a motorway trip this week (first one since the drive home from Dr Lee) and I am seriously enjoying these coilovers.
Over a certain stretch of the A2/M2 I used to get a bouncing motion as the FK's could not damp properly (you often see this on very low cars going down the motorway).
None of that with the BC's. Not sure if the increased ride height helps here or just better dampers, suspect a bit of both.
Real pleasure on the motorway now. Alert but not fidgety and harsh.
Then took my 18's off for a refurb and put on my 17inch staggered style 32's and the car rides even better!
The rubber is a bit old on these tyres but the increased side wall and narrower width make for smoother going and more movement in corners (in a good way) but overall less direct and more understeer (oversteer on demand).
I can probably firm up the shocks a bit when on the 17's.
17's are ideal for bumpy roads. When I can afford a really nice dished set of 17's I think that's what will go on next but for now the 18's are going to refurbished to a better than new finish with a few touches to set them off.
The spring pads at the top of the rear shocks where removed by previous owner for the FK's and I suspect this is causing harshness rather than actually bottoming out.
So got a pair on order from BMW and once here car goes in for full corner weighting and alignment...should be even sweeter then...
So had a motorway trip this week (first one since the drive home from Dr Lee) and I am seriously enjoying these coilovers.
Over a certain stretch of the A2/M2 I used to get a bouncing motion as the FK's could not damp properly (you often see this on very low cars going down the motorway).
None of that with the BC's. Not sure if the increased ride height helps here or just better dampers, suspect a bit of both.
Real pleasure on the motorway now. Alert but not fidgety and harsh.
Then took my 18's off for a refurb and put on my 17inch staggered style 32's and the car rides even better!
The rubber is a bit old on these tyres but the increased side wall and narrower width make for smoother going and more movement in corners (in a good way) but overall less direct and more understeer (oversteer on demand).
I can probably firm up the shocks a bit when on the 17's.
17's are ideal for bumpy roads. When I can afford a really nice dished set of 17's I think that's what will go on next but for now the 18's are going to refurbished to a better than new finish with a few touches to set them off.
The spring pads at the top of the rear shocks where removed by previous owner for the FK's and I suspect this is causing harshness rather than actually bottoming out.
So got a pair on order from BMW and once here car goes in for full corner weighting and alignment...should be even sweeter then...
Finally tidied up the rear parcel shelf carpet and put the plastic lugs back etc, fiddly work so had been putting it off.
My Winblox deflector has clever cutouts at the rear bottom edges so I can reach in and adjust my rear damper speed easily.
I like how the adjusters are just visible from outside when the good is up.
Would love some stickers over the knobs with GHD logos and 'hot' and 'cold' for the complete hairdresser effect(!)
My Winblox deflector has clever cutouts at the rear bottom edges so I can reach in and adjust my rear damper speed easily.
I like how the adjusters are just visible from outside when the good is up.
Would love some stickers over the knobs with GHD logos and 'hot' and 'cold' for the complete hairdresser effect(!)
I am interested in this as it is an issue I have seen on a number of cars in the past and on my M it is sometimes an issue.... my M is currently having a few bits of work done which I hope will resolve many issues but I always thought the shift issue was more to do with the gearbox ins rather than diff bushes?
BTW... did those bushes not register on the MOT?
@bertiejaffa It's more a combination of all the bushes allowing the rear to sit p***** making the alignment sit out. When I lowered Dino's chassis that diff bush fell out, but looked ok sat under the weight. In fact all the bushes were the worst I have seen this is most likely due to how much the car has been lowered and the wheel offset.
^ What Lee said.
But bear in mind this a BMW so if you have had Jap cars you'll be used to rifle bolts shifts that I never experienced on any BMW.
I too thought my clutch was worn or something in the box but the change in bushes (both subframe and diff) have made the shift as good as when new I reckon.
Never had advisory on MOT for bushes, only have had advisory for corroded brake pipes, nothing else...
The other thing is the amount of power that gets sapped by worn bushes, I thought my vanos was going as it felt bogged down off the line, new bushes and it just pulls now!
But bear in mind this a BMW so if you have had Jap cars you'll be used to rifle bolts shifts that I never experienced on any BMW.
I too thought my clutch was worn or something in the box but the change in bushes (both subframe and diff) have made the shift as good as when new I reckon.
Never had advisory on MOT for bushes, only have had advisory for corroded brake pipes, nothing else...
The other thing is the amount of power that gets sapped by worn bushes, I thought my vanos was going as it felt bogged down off the line, new bushes and it just pulls now!
CORNER WEIGHTS AND ALIGNMENT
So I finally got the corner weights and alignment done
The short update is this:
I've already gushed about how great the car feels before the alignment and corner weights. After this it's even better. Really can't believe a Z3 can be this planted, confident and fun to drive!
Love it!
The longer update.
@Lee had managed to get the cross weights pretty close, there was just 2% difference which without professional garage equipment is impressive!!
Chris at Kent MX-5 who did my car said on the road I would probably not notice that small of a difference and I didn't really, the car felt so good when I got it back from Lee I was wondering wether I should spend the extra doing the corner weighting. However it did need alignment anyway and I just wouldn't be 'sure' until it was done that it was all 100%.
The big changes I could instantly feel are:
-1 degree camber on the front. What a revelation to steering precision, feel and bite.
Much less hunting over bumps and the front just hooks up, understeer pretty much eliminated.
Front feels welded to the road.
A point to note for others doing this set up- Chris originally wanted to dial in -1,5 degree camber but with the adjustable top mounts he could only get -1,5 on one side and not the other hence settling for -1 on both sides.
Given my tyres are wide (225 but fitted over a wide rim) this is still plenty make a difference. For those who want to track it and run more camber than you'll probably needed some other changes to allow more camber than what just the top mounts can offer.
I also had the front lowered slightly and can notice that from the drivers seat I feel that I am more on top of the front end and in control. I'll admit to wanting a slight nose down stance for looks too.
Alignment - no pulling to the right and just feels sweet. It used to pull a bit to the right.
These are weights now:
Weight if driver: 75kg
1/4 tank fuel.
LF 335kg RF371kg
LR 338kg RR364kg
Cross weight 50,3%
Total weight 1406kg
Ride height
LF 5"9/16 RF 5"8/16 (from front ARB)
LR 7"7/16 RR 7"3/8 (from rear beam)
Camber -1 degree both sides (front)
Front toe: 0,5mm toe in
I looked around for places for corner weights and all I found have Motorsport backgrounds but the thing is most are too busy with track season upon us. Chris at MX5 services is also busy with track work but is geared to people with road cars too. So although it took a few weeks to make a date that worked for us both he was helpful to accommodate. Great service from a knowledgable guy who has raced RWD big engined car for years.
I'll paste in some bits from his site here to explain the corner weighting and importantly the equipment he uses (ensures that the car is truly level):
MODS: hope this ok?
http://www.kentmx5.co.uk/mx5-suspension-set-up/
Here at Kent MX5 Services, we are specialists in full suspension set up, 4 wheel laser alignment plus much more.
We have all the latest digitail and laser alignment equipment:
Full corner weighting and cross weighting facilties by Long Acre as used in USA by NASCAR
Full Lite Align 4 wheel laser alignment
Fully adjustable flat floor with laser level for accurate suspension readings.
All castor, camber, bump steer , Akerman and ride height / rake adjustment equipment.
Fast Road / race spec. suspension and brake upgrade packages supplied and fitted.
Again, due to our vast experience in suspension tuning, not just with the MX5, but with various motorsport disciplines over many years, we have various set up options that we will offer your MX5.
There are various theories on suspension tuning, and what alterations do x, y and z, but there is a lot of truth in the phrase " there is more than one way to skin a cat". Our knowledge has been gained by extensive and exhaustive testing over many years, and we feel we have the best set up options available for your MX5 in all disciplines, from fast road use to full race specifications.
Corner weighting (and cross weighting) a car is the most important chassis tuning process you can do for any car. It is nothing short of Critical.
Corner weighting.....what is it?
Corner weighting a car allows precise vehicle weight distribution which is critical for that ultimate car balance on the track. It is highly regarded as the most important chassis tuning tool available, and is the only true way to obtain that perfect balance of a car. Of course castor, camber, ackerman angles etc all matter, BUT, a degree or minute here and there does not have the same effect to a car that corner weighting / cross weighting does. Cross weights ideally should be 50%, but depending on what discipline you are doing, can easily be adjusted with a turn here and a turn there on spring platforms. For example, we run 51% cross weight at Brands Hatch as the circuit has more right handers than left.
The classic symptom of a car that has not been corner weighted is the difference in balance of a car through right hand corners compared to left. On an exagerrated basis, if you have oversteer in corners going one direction, and understeer in the other, your corner weights, or more to the point cross weight, are wrong. In fact it has to be said, when setting up a car that does NOT have a central driving position, it is in fact the cross weight you go buy, and not as what most people think, the corner weights. It is all about making sure the percentages between the LF and LR are the same as the RF and RR, regardless of their actual corner weight. And yes....the driver is needed for corner weighting a car. For at least the first set up seesion anyway, and providing accurate measurements have been recorded during the set up process, without a driver is possible. But rule of thumb....WITH DRIVER IN THE CAR.
How long does this take, and how much?
Well it depends on what you want done of course.....and what is needed. A road car will not need as much as a full race car set up. We have extremely accurate and complex systems that we use, which need to be set up each time for each car. We know from experience, our equipment measures more accurately than the 4 wheel alignment systems used in most garages that are on fixed ramps. When permanent ramps / alignment stations have been in garages for a while, there is what only can be an assumption that the ramp the car is on is still level. We have had a few customers witness this. When the car was on the ramp, they could visibly see that the ramp was not sitting level compared to the floor and the wall. Therefore whilst the laser was level, the car wasn't. We then had to redo the cars castor and camber angles using our adjustabe laser flat floor.
Throughout the whole set up process, our adjustable laser flat floor is always used. It is the only way to be accurate. We charge £100 which allows all the equipment to be set up, and all your cars angles etc to be measured. This allows us 2 hours, and of course included in this are any alterations done in that period. We then charge £12.50 every 15 minutes there after. WE DO NOT KNOW THE WORDS RUSH OR HURRY. Accuracey takes time. If your MX5 has coil over suspension, and is used for track disciplines, then corner weighting etc is done. However, for a full race spec set up, with full set up sheets available afterwards, the price is £320, and we will need you car for a day.
Please note, that any broken compents / snapped bolts are not included in these costs. New parts / bolts will be charged in addition, and labour at 15 minute intervals on top (£12.50). Kent MX5 Services do not except any responsability for any broken parts / bolts.
So I finally got the corner weights and alignment done
The short update is this:
I've already gushed about how great the car feels before the alignment and corner weights. After this it's even better. Really can't believe a Z3 can be this planted, confident and fun to drive!
Love it!
The longer update.
@Lee had managed to get the cross weights pretty close, there was just 2% difference which without professional garage equipment is impressive!!
Chris at Kent MX-5 who did my car said on the road I would probably not notice that small of a difference and I didn't really, the car felt so good when I got it back from Lee I was wondering wether I should spend the extra doing the corner weighting. However it did need alignment anyway and I just wouldn't be 'sure' until it was done that it was all 100%.
The big changes I could instantly feel are:
-1 degree camber on the front. What a revelation to steering precision, feel and bite.
Much less hunting over bumps and the front just hooks up, understeer pretty much eliminated.
Front feels welded to the road.
A point to note for others doing this set up- Chris originally wanted to dial in -1,5 degree camber but with the adjustable top mounts he could only get -1,5 on one side and not the other hence settling for -1 on both sides.
Given my tyres are wide (225 but fitted over a wide rim) this is still plenty make a difference. For those who want to track it and run more camber than you'll probably needed some other changes to allow more camber than what just the top mounts can offer.
I also had the front lowered slightly and can notice that from the drivers seat I feel that I am more on top of the front end and in control. I'll admit to wanting a slight nose down stance for looks too.
Alignment - no pulling to the right and just feels sweet. It used to pull a bit to the right.
These are weights now:
Weight if driver: 75kg
1/4 tank fuel.
LF 335kg RF371kg
LR 338kg RR364kg
Cross weight 50,3%
Total weight 1406kg
Ride height
LF 5"9/16 RF 5"8/16 (from front ARB)
LR 7"7/16 RR 7"3/8 (from rear beam)
Camber -1 degree both sides (front)
Front toe: 0,5mm toe in
I looked around for places for corner weights and all I found have Motorsport backgrounds but the thing is most are too busy with track season upon us. Chris at MX5 services is also busy with track work but is geared to people with road cars too. So although it took a few weeks to make a date that worked for us both he was helpful to accommodate. Great service from a knowledgable guy who has raced RWD big engined car for years.
I'll paste in some bits from his site here to explain the corner weighting and importantly the equipment he uses (ensures that the car is truly level):
MODS: hope this ok?
http://www.kentmx5.co.uk/mx5-suspension-set-up/
Here at Kent MX5 Services, we are specialists in full suspension set up, 4 wheel laser alignment plus much more.
We have all the latest digitail and laser alignment equipment:
Full corner weighting and cross weighting facilties by Long Acre as used in USA by NASCAR
Full Lite Align 4 wheel laser alignment
Fully adjustable flat floor with laser level for accurate suspension readings.
All castor, camber, bump steer , Akerman and ride height / rake adjustment equipment.
Fast Road / race spec. suspension and brake upgrade packages supplied and fitted.
Again, due to our vast experience in suspension tuning, not just with the MX5, but with various motorsport disciplines over many years, we have various set up options that we will offer your MX5.
There are various theories on suspension tuning, and what alterations do x, y and z, but there is a lot of truth in the phrase " there is more than one way to skin a cat". Our knowledge has been gained by extensive and exhaustive testing over many years, and we feel we have the best set up options available for your MX5 in all disciplines, from fast road use to full race specifications.
Corner weighting (and cross weighting) a car is the most important chassis tuning process you can do for any car. It is nothing short of Critical.
Corner weighting.....what is it?
Corner weighting a car allows precise vehicle weight distribution which is critical for that ultimate car balance on the track. It is highly regarded as the most important chassis tuning tool available, and is the only true way to obtain that perfect balance of a car. Of course castor, camber, ackerman angles etc all matter, BUT, a degree or minute here and there does not have the same effect to a car that corner weighting / cross weighting does. Cross weights ideally should be 50%, but depending on what discipline you are doing, can easily be adjusted with a turn here and a turn there on spring platforms. For example, we run 51% cross weight at Brands Hatch as the circuit has more right handers than left.
The classic symptom of a car that has not been corner weighted is the difference in balance of a car through right hand corners compared to left. On an exagerrated basis, if you have oversteer in corners going one direction, and understeer in the other, your corner weights, or more to the point cross weight, are wrong. In fact it has to be said, when setting up a car that does NOT have a central driving position, it is in fact the cross weight you go buy, and not as what most people think, the corner weights. It is all about making sure the percentages between the LF and LR are the same as the RF and RR, regardless of their actual corner weight. And yes....the driver is needed for corner weighting a car. For at least the first set up seesion anyway, and providing accurate measurements have been recorded during the set up process, without a driver is possible. But rule of thumb....WITH DRIVER IN THE CAR.
How long does this take, and how much?
Well it depends on what you want done of course.....and what is needed. A road car will not need as much as a full race car set up. We have extremely accurate and complex systems that we use, which need to be set up each time for each car. We know from experience, our equipment measures more accurately than the 4 wheel alignment systems used in most garages that are on fixed ramps. When permanent ramps / alignment stations have been in garages for a while, there is what only can be an assumption that the ramp the car is on is still level. We have had a few customers witness this. When the car was on the ramp, they could visibly see that the ramp was not sitting level compared to the floor and the wall. Therefore whilst the laser was level, the car wasn't. We then had to redo the cars castor and camber angles using our adjustabe laser flat floor.
Throughout the whole set up process, our adjustable laser flat floor is always used. It is the only way to be accurate. We charge £100 which allows all the equipment to be set up, and all your cars angles etc to be measured. This allows us 2 hours, and of course included in this are any alterations done in that period. We then charge £12.50 every 15 minutes there after. WE DO NOT KNOW THE WORDS RUSH OR HURRY. Accuracey takes time. If your MX5 has coil over suspension, and is used for track disciplines, then corner weighting etc is done. However, for a full race spec set up, with full set up sheets available afterwards, the price is £320, and we will need you car for a day.
Please note, that any broken compents / snapped bolts are not included in these costs. New parts / bolts will be charged in addition, and labour at 15 minute intervals on top (£12.50). Kent MX5 Services do not except any responsability for any broken parts / bolts.
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^^^ Great reading, had my first outing with the BCs last Tuesday at Cadwell, they performed really well but not convicted about the rear on the public road, bit too harsh and crashey.
Are you running the 6kg or 8kg rear springs Brian?
I'm on 6kg all round.
I agree with the rear on 'public' roads (code for 3rd world rubbish roads!).
The actual control is good and it never feels like it loses contact but it sounds and at times feels harsh on the really bad bits.
In normal hood surfaces it's fine.
The FK's I had prevails sounded and felt less harsh but funnily would be skittish on the rear.
The BC's are better now with a bit of height that I dialed in.
I forgot to mention the rear upper spring pads- I got some but there is no way to fit them on top of the BC spring.
The rears are just uprated parts, not actually coilovers so I believe we can switch out dampers and springs easily enough. What do you reckon can be done to improve it?
I've seen that the Z3 race car had had a true coilover conversion done. The should allow longer springs.
Ps what damper stiffness were you running on track Brian?
I'm on 6kg all round.
I agree with the rear on 'public' roads (code for 3rd world rubbish roads!).
The actual control is good and it never feels like it loses contact but it sounds and at times feels harsh on the really bad bits.
In normal hood surfaces it's fine.
The FK's I had prevails sounded and felt less harsh but funnily would be skittish on the rear.
The BC's are better now with a bit of height that I dialed in.
I forgot to mention the rear upper spring pads- I got some but there is no way to fit them on top of the BC spring.
The rears are just uprated parts, not actually coilovers so I believe we can switch out dampers and springs easily enough. What do you reckon can be done to improve it?
I've seen that the Z3 race car had had a true coilover conversion done. The should allow longer springs.
Ps what damper stiffness were you running on track Brian?
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I put the 8kgs in Dino but could not get them low enough for me, they are about 25-30mm taller than the 6kg springs, I am going to speak with BC to see what they recommend
I got the upper spring pads with bump stops in with mine.
I think I'm going to pop my Eibach springs back in the rear just now until I hear from BC, with the stiffness on the dampers turned to hard the ride is brutal, with the stiffness of the dampers turned down it sounds as if the trailing arms are hitting against the stops, I have tried various settings but have not found the optimum one yet.
On the track I had 20 clicks from soft on the front and 15 on the rear.
Hi Brian,
How much are the rears shocks extended by?
I extends them as far as possible (so that I just see the end if the screw thread through hole at the bottoms). This improved things a lot.
Although I've read on M3 cutters that winding the shock in is better...
What damper setting are you using on road?
I'm now around 15 at the rear and 16 at the front.
20 at the front is firm, must have been pretty sharp...
15 at the rear I find good, any harder and it's easy to spin up, good for deifying I guess!
Interesting that you got the upper pads in, I was told they would go in...was it hard to get them in?
Not sure if this actually helps though, possibly making the spring a bit shorter?
When I had Chris in the car I went over some bad ruts so he could hear the rear over bad bumps and asked what he thought and he said it was just typical of a firm spring set up.
Let me know what you hear back from BC. I don't think there are many Z's out in UK with them yet..
How much are the rears shocks extended by?
I extends them as far as possible (so that I just see the end if the screw thread through hole at the bottoms). This improved things a lot.
Although I've read on M3 cutters that winding the shock in is better...
What damper setting are you using on road?
I'm now around 15 at the rear and 16 at the front.
20 at the front is firm, must have been pretty sharp...
15 at the rear I find good, any harder and it's easy to spin up, good for deifying I guess!
Interesting that you got the upper pads in, I was told they would go in...was it hard to get them in?
Not sure if this actually helps though, possibly making the spring a bit shorter?
When I had Chris in the car I went over some bad ruts so he could hear the rear over bad bumps and asked what he thought and he said it was just typical of a firm spring set up.
Let me know what you hear back from BC. I don't think there are many Z's out in UK with them yet..
I have mine set in a little, I did originally have them set like yours to match the length of the OEM shocks but after reading all the blurb it suggested that when you lower the car on the spring adjusters you need to lower the shocks too! Its a learning game so I may just wind them back out to see.
Not too far off you, 15 ant the front and 10 at the rear, I must say the front is superb no issues whatsoever, its just the rear I need to get right.
Should not make the spring any shorter as the pads sit above the spring, the bump stop comes through the spring adjuster, If i am hitting the bump stops (which I am) the trailing arms are being raised too high. This is why I wanted 8KG springs.
Will do
@Brian H
Just thinking a couple of things. I read the bit about adjusting the se pings and shocks together in the instructions too (interesting English...!) but upon speaking with the suspension guy Chris he said they do this to cover themselves so that people don't adjust the shock extra long and spring extra short so that the spring could jump out when the car rises over a bump (highly unlikely but you never know what people could get up to).
So I extended the shock fully but did make sure that even when fully extended the springs were long enough to have just a bit of tension so no chance of them moving about.
Interesting point is that HSD apparently use a threaded body shock body and adjustable springs like this too.
Re the top spring pad, it's quite thick and from what I understand adding the pad on the spring adds the same plus a certain amount more to the ride height.
So having them in is making you run the springs shorter to to get the ride height you want?
Having the springs shorter than needed is not what we really want here is it? More travel the better I think.
Out of interest did you drive it with 8kg springs?
Do the Eibachs have a 'kg' measurement too?
You right about being a learning game but without many others out there is seems like it's just us with Z's so far on BC's (!). Plenty of M3's with them over on M3 cutters.
Just thinking a couple of things. I read the bit about adjusting the se pings and shocks together in the instructions too (interesting English...!) but upon speaking with the suspension guy Chris he said they do this to cover themselves so that people don't adjust the shock extra long and spring extra short so that the spring could jump out when the car rises over a bump (highly unlikely but you never know what people could get up to).
So I extended the shock fully but did make sure that even when fully extended the springs were long enough to have just a bit of tension so no chance of them moving about.
Interesting point is that HSD apparently use a threaded body shock body and adjustable springs like this too.
Re the top spring pad, it's quite thick and from what I understand adding the pad on the spring adds the same plus a certain amount more to the ride height.
So having them in is making you run the springs shorter to to get the ride height you want?
Having the springs shorter than needed is not what we really want here is it? More travel the better I think.
Out of interest did you drive it with 8kg springs?
Do the Eibachs have a 'kg' measurement too?
You right about being a learning game but without many others out there is seems like it's just us with Z's so far on BC's (!). Plenty of M3's with them over on M3 cutters.
This is very interesting fellows! Keep it coming, please! JIM
Good call, Im going to elongate the shock back to the setting I first had, with my rear H&R ARB and drop links there is no way the springs will pop out, the roll bar hits the drive shafts first.
The top of the spring pad is 2 - 3mm thick so not too bad, I think I would rather have it in than not, I cannot see the tolerance being this small.
Not tried it with the 8kg springs, I did not want to use them until BC came back to me, I may have to return them.
I have looked everywhere for this info but to no avail, most other manufacturers seem to use spring rates rather than Kgs.
I'm sure well get there
Had an email from BC racing, not too helpful really, I asked about the rear springs and the drop links in the supplied kit, I have to supply pictures of the front setup so that they can see which type of drop links we use and they informed me that the 8kg springs are 10mm longer than the 6kg,
I have had the 6kg in place with approx 20mm of spacing on the spring adjuster, with this setup the car sat really nice but the ride was too harsh, on track, great but on the public roads it is a no no. I have installed the 8kg springs with no spring adjustment screws, just the seat pad and the car is sat higher than it was but ride quality is 100 times better, no more looking ahead to seek out every imperfection in the road so that I could avoid it. I hope over the next couple of days/weeks the springs will sag a little but I can live with how it sits just now.
I'll update my own thread at some point but thought I would put this here as a conclusion to the discussions above.
I have had the 6kg in place with approx 20mm of spacing on the spring adjuster, with this setup the car sat really nice but the ride was too harsh, on track, great but on the public roads it is a no no. I have installed the 8kg springs with no spring adjustment screws, just the seat pad and the car is sat higher than it was but ride quality is 100 times better, no more looking ahead to seek out every imperfection in the road so that I could avoid it. I hope over the next couple of days/weeks the springs will sag a little but I can live with how it sits just now.
I'll update my own thread at some point but thought I would put this here as a conclusion to the discussions above.
Hi Brian,
Thanks for the update.
The drop links they sent the kit are are way too long, I think they are e46 items.
Is the 8kg in with the top pad and the bottom pad?
Did you try the 6kg without an adjusters in?
Interesting to hear such a big improvement.
I find the 6kg ok, yes it's stiff but coming from what I had before it's better but if the 8kg is such a big improvement I need to look into this.
Hoping the 8kg springs are not too much extra to buy?
Can you get some pics up of your ride height now?
Are you going to be down south anytime, would love to compare ride quality!
I'm actually puzzled how a stiffer spring improves the ride actually, I guess it removes an bottoming out but I would have thought the trade off would be even more harshness?
Thanks for the update.
The drop links they sent the kit are are way too long, I think they are e46 items.
Is the 8kg in with the top pad and the bottom pad?
Did you try the 6kg without an adjusters in?
Interesting to hear such a big improvement.
I find the 6kg ok, yes it's stiff but coming from what I had before it's better but if the 8kg is such a big improvement I need to look into this.
Hoping the 8kg springs are not too much extra to buy?
Can you get some pics up of your ride height now?
Are you going to be down south anytime, would love to compare ride quality!
I'm actually puzzled how a stiffer spring improves the ride actually, I guess it removes an bottoming out but I would have thought the trade off would be even more harshness?