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      03-29-2009, 01:43 PM   #1
J08M3
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Suspension drop help/suggestions needed

I'm pretty good about technology when it comes to cars and working on them. But suspension is my weak point so I need some help and suggestions on what will be the best way to go on my car.

I have a non-EDC car and would like it to sit lower than it does from the factory. No more than 1/2" though, I don't like them slammed to the ground. I also am running OEM 19s w/ PS2s and don't want any issues with tires rubbing. I don't want to sacrifice any performance. I really like the feel of OEM setup, it's quite stiff and handles good, yet comfortable for daily driving. It's just a bit too high. I'm looking for something that can give me the same comfort (or close to) and at least same if not better handling.

What do you guys suggest and why? Approximately how much does this cost?

thanks
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      03-29-2009, 07:40 PM   #2
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Quote:
Originally Posted by J08M3 View Post
I'm pretty good about technology when it comes to cars and working on them. But suspension is my weak point so I need some help and suggestions on what will be the best way to go on my car.

I have a non-EDC car and would like it to sit lower than it does from the factory. No more than 1/2" though, I don't like them slammed to the ground. I also am running OEM 19s w/ PS2s and don't want any issues with tires rubbing. I don't want to sacrifice any performance. I really like the feel of OEM setup, it's quite stiff and handles good, yet comfortable for daily driving. It's just a bit too high. I'm looking for something that can give me the same comfort (or close to) and at least same if not better handling.

What do you guys suggest and why? Approximately how much does this cost?

thanks

It depends how much you want to lower your car. The following is generally the lowering aggressiveness among different brand of springs..

Dinan < Eibach < HR < RD Sport
0.5" all around < 0.8"F/0.6"R < 1.0"F/0.6"R < 1.0+"F/0.6+"R

However obviously the more you lower the more you run on the bumpstops, which IMO is not the best idea... If you want to be safe and a subtle drop, then go with the Dinan or Eibach, for more aggressive look then go with HR or RD Sport.
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      03-29-2009, 07:45 PM   #3
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Quote:
Originally Posted by psuwcc112 View Post
It depends how much you want to lower your car. The following is generally the lowering aggressiveness among different brand of springs..

Dinan < Eibach < HR < RD Sport
0.5" all around < 0.8"F/0.6"R < 1.0"F/0.6"R < 1.0+"F/0.6+"R

However obviously the more you lower the more you run on the bumpstops, which IMO is not the best idea... If you want to be safe and a subtle drop, then go with the Dinan or Eibach, for more aggressive look then go with HR or RD Sport.
Thanks. More subtle is what I want. About .5" sounds perfect. How will these affect performance? Are they as good as OEM? Or does performance and comfort both drop?
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      03-29-2009, 08:03 PM   #4
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Quote:
Originally Posted by psuwcc112 View Post
It depends how much you want to lower your car. The following is generally the lowering aggressiveness among different brand of springs..

Dinan < Eibach < HR < RD Sport
0.5" all around < 0.8"F/0.6"R < 1.0"F/0.6"R < 1.0+"F/0.6+"R

However obviously the more you lower the more you run on the bumpstops, which IMO is not the best idea... If you want to be safe and a subtle drop, then go with the Dinan or Eibach, for more aggressive look then go with HR or RD Sport.
Great info!!!
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      03-29-2009, 08:04 PM   #5
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Quote:
Originally Posted by J08M3 View Post
Thanks. More subtle is what I want. About .5" sounds perfect. How will these affect performance? Are they as good as OEM? Or does performance and comfort both drop?
I think if you want to play safe then perhaps go with Dinan. Dinan springs with its modified shorter spring guard and bumpstops is the only setup that can keep the stock shock travel without riding on the bumpstop all the time. Some people in the forum believe shorten the stock shock travel with shorter spring can worsen performance, although there has been any track performance comparsion between stock and aftermarket spring to back it up... I went with Eibach because i dont feel like of paying premium on the Dinan spring just to keep the warranty, beside i feel i will never stress the car to the extent that i will feel the performance different. So far, i have been pretty happy with Eibach spring. Both ride comfort and handling feel like stock, perhaps just a slightly stiffer.. In case if your concerning about your significant other..It definitely pass the WIFE/GF test so far
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      03-29-2009, 08:09 PM   #6
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J08M3, one thing to consider apart from what has been mentioned already regarding drop distances and suspension travel is the actual stiffness of the springs. I believe all of the aftermarket springs mentioned above will have higher spring rates than stock springs, but I have not seen any force-displacement data on any of them. If you increase the spring rate considerably, you will need to modify your dampers as well at some point, but without having any actual values to consider, that is kind of up in the air. I recently decided to go with the Dinan setup. They do spend a significant amount of time developing their suspension mods, and they only do BMWs, so their efforts seem more focused to me. And, I have read several glowing reviews of Dinan suspension setups with documented improvements in laptimes vs stock and so on, and that does not seem to come at the expense of daily driving comfort. It is indeed more expensive though.
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      03-29-2009, 08:18 PM   #7
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Quote:
Originally Posted by J08M3 View Post
I'm pretty good about technology when it comes to cars and working on them. But suspension is my weak point so I need some help and suggestions on what will be the best way to go on my car.

I have a non-EDC car and would like it to sit lower than it does from the factory. No more than 1/2" though, I don't like them slammed to the ground. I also am running OEM 19s w/ PS2s and don't want any issues with tires rubbing. I don't want to sacrifice any performance. I really like the feel of OEM setup, it's quite stiff and handles good, yet comfortable for daily driving. It's just a bit too high. I'm looking for something that can give me the same comfort (or close to) and at least same if not better handling.

What do you guys suggest and why? Approximately how much does this cost?

thanks
Btw, looks like you dont have EDC, why not just go with coil system including both shocks and springs...? I think most of us swapping the spring only because we want to keep the EDC..
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      03-30-2009, 06:30 AM   #8
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Quote:
Originally Posted by psuwcc112 View Post
Btw, looks like you dont have EDC, why not just go with coil system including both shocks and springs...? I think most of us swapping the spring only because we want to keep the EDC..
Yea, I'm not educated enough in the suspension area of the car to know which way is best to go. From what you've said so far DINAN springs seems the best way to get what I want.

But should I go for a coil system both shocks and springs? Is that way more expensive? I don't mind paying a bit more if quality/performance is better and it will get me what I want. Just want to make sure I get the right thing.

thanks for the help so far
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      03-30-2009, 02:55 PM   #9
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How long should it take if I choose to install a set of Dinan springs? I asked my BMW dealer who sells Dinan stuff and they told me 9 hours. That sounds a little long to me?? I could probably do this on jack stands alone in my garage in less time and I've never tried to do this before.

Any opinions?
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      03-30-2009, 03:14 PM   #10
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Quote:
Originally Posted by J08M3 View Post
Yea, I'm not educated enough in the suspension area of the car to know which way is best to go. From what you've said so far DINAN springs seems the best way to get what I want.

But should I go for a coil system both shocks and springs? Is that way more expensive? I don't mind paying a bit more if quality/performance is better and it will get me what I want. Just want to make sure I get the right thing.

thanks for the help so far
I think coil system with proper tuning is probably the best way to go if dropping couple grands on a new set of suspension is not a issue. But again, there is currently no sufficient data or evidence that can gurantee that coil system perform better than stock on the track....
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      03-30-2009, 03:18 PM   #11
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Quote:
Originally Posted by J08M3 View Post
How long should it take if I choose to install a set of Dinan springs? I asked my BMW dealer who sells Dinan stuff and they told me 9 hours. That sounds a little long to me?? I could probably do this on jack stands alone in my garage in less time and I've never tried to do this before.

Any opinions?
I think that just the way it is with Dinan.. I am not sure if you install yourself you will still be able to keep the Dinan warranty though.. You may want double check with some members that already have their Dinan spring intalled
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      03-30-2009, 05:09 PM   #12
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Quote:
Originally Posted by J08M3 View Post
How long should it take if I choose to install a set of Dinan springs? I asked my BMW dealer who sells Dinan stuff and they told me 9 hours. That sounds a little long to me?? I could probably do this on jack stands alone in my garage in less time and I've never tried to do this before.

Any opinions?
The 8.9 hour quote includes alignment, so the real install quote is more like 7 hours, which is still on the high side. You can take the springs and the bump stops to any local shop. To the best of my knowledge, they don't need to be installed by a Dinan dealer for the Dinan warranty to be in effect as long as the installation is done properly (it's a little more than a spring replacement).
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      03-30-2009, 08:09 PM   #13
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Quote:
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The 8.9 hour quote includes alignment, so the real install quote is more like 7 hours, which is still on the high side. You can take the springs and the bump stops to any local shop. To the best of my knowledge, they don't need to be installed by a Dinan dealer for the Dinan warranty to be in effect as long as the installation is done properly (it's a little more than a spring replacement).
yea, I wouldn't go to the dealer for this anyway. But since they were listed on the Dinan site I figured I give them a call to see what they'd say.

Next question is are you supposed to do the alignment immediately after just a spring change? I know when you replace everything people say drive a week or so until all new stuff settles out then align. Is it necessary to wait when just replacing springs?
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      03-31-2009, 07:33 AM   #14
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Next question is are you supposed to do the alignment immediately after just a spring change? I know when you replace everything people say drive a week or so until all new stuff settles out then align. Is it necessary to wait when just replacing springs?
People claim driving around is necessary. Neither BMW nor Dinan suggests that. I personally do not see what the point of driving around for a week is. It's not as if the spring will plastically deform or anything. If it does, you probably have a bad spring. I can see the spring settling in around the support structures, but I don't see how a short drive will not achieve that. Anyway, you can do it either way I guess. It's not a big deal.
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      03-31-2009, 09:24 AM   #15
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If you don't have EDC then I say do coilovers, regardless of your desire. You're going to get a better result with coilovers versus springs, and you can adjust the ride height to suit your taste.
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      03-31-2009, 09:37 AM   #16
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If you don't have EDC then I say do coilovers, regardless of your desire. You're going to get a better result with coilovers versus springs, and you can adjust the ride height to suit your taste.
Any suggestions on what I should go with?
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      03-31-2009, 10:31 AM   #17
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If I didn't have EDC I probably wouldn't waste my money on springs. I would just go with the coilovers.

However they are much more expensive, the sets cost 2k, and I hear installation and the works will run you another thousand.
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      04-01-2009, 08:11 PM   #18
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Which coilovers are recommended if I just want a .5" drop? This solution better than just going with the Dinan springs?

Any downfalls to going with just springs? Will this small drop ruin my OEM shocks?
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      04-02-2009, 12:28 AM   #19
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I have been contemplating abt this for months - I just ordered eibachs from tire rack.

The drop looks aggressive enough and the ride comfort is still there, maybe 10% stiffer which is not noticeable.

Like you - I drive around a lot on rough roads in Philly. I'm up in New York every other weekend as well and I would hate to have to slowdown for every single pot hole and bumps on the road.

Will keep you updated regarding the install, should be fun.
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      04-02-2009, 06:10 AM   #20
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Yes, please do keep me updated. How much drop do you expect from them?
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