GMG Springs + Bilstein B8 Damptronic struts/shocks
#16
04-25-2013, 09:10 AM
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#17
04-25-2013, 09:17 AM
Would be great if kitw found the thread and chimed in on his experience.
Running springs on stock shocks doesn't offer much of a solution at all to me. The car is pretty low already, so lowering that much is not really needed. The biggest issue is that that the shocks are too soft on normal mode and too stiff on sport. I've driven the Damptronic coilover and it offers the perfect blend; normal is a bit stiffer so not mushy and sport is firm, but actually usable.
The other huge benefit of a straight spring/shock swap is that the installation will be much cheaper. No corner balancing or setting the height. In order to adjust the height, you need to load the car measure, get under it and adjust, reload the car and measure, etc. It can be time consuming and I had a tuner charge me quite a bit of money to set a car up once. This eliminates that cost completely. Aside from removing the stock strut hat, this should be a very easy install.
I Googled the shocks and quickly noticed an auto parts company selling them much cheaper than the typical "tuner" price...
Running springs on stock shocks doesn't offer much of a solution at all to me. The car is pretty low already, so lowering that much is not really needed. The biggest issue is that that the shocks are too soft on normal mode and too stiff on sport. I've driven the Damptronic coilover and it offers the perfect blend; normal is a bit stiffer so not mushy and sport is firm, but actually usable.
The other huge benefit of a straight spring/shock swap is that the installation will be much cheaper. No corner balancing or setting the height. In order to adjust the height, you need to load the car measure, get under it and adjust, reload the car and measure, etc. It can be time consuming and I had a tuner charge me quite a bit of money to set a car up once. This eliminates that cost completely. Aside from removing the stock strut hat, this should be a very easy install.
I Googled the shocks and quickly noticed an auto parts company selling them much cheaper than the typical "tuner" price...
#19
07-01-2013, 10:34 AM
Another thread revive. I've been looking around at prices for these shocks, and it appears they are around $2K for all 4 vs. $2750 for the complete B16 coilover kit. Once you buy the GMG lowering springs they are the same price. Maybe I am missing something, but It seems to me that the coilovers would be a better option if they're roughly the same price.
#20
07-01-2013, 12:21 PM
Not so sure. Granted, the struts are 1800, but the gmg Springs seem a bit overpriced, given the Eibachs or h&rs are only 320. (Half the price) Fixed springs assure you that theinstall will be perfect. Some shops will charge several hundred more for a "corner balance" to adjust the springs. No need with fixed springs. Takes away the guess work. The Bilstein are now 2700 from TireRack-maybe cheaper from others. Installed, the diff could be $1000.
#21
07-01-2013, 01:03 PM
Just trying to help here. It's a excellent alternative, a few things I would add:
1. Be careful with the springs you pick and select one per your taste (no right or wrong): GMG is stiffer, H&R is like stock, and Eibach I don't know. Very true the costs are different but the spring rates may not be all the same.
2. You can't adjust height with B8, unlike B16 Damptronic. With B8 your car will be lowered a fixed 24mm, with B16 Damptronic it's adjustable 5mm to 24mm. A consideration for those in big cities.
3. Corner balancing is not part of a coilover install - tuner should never charge you for that and run away from anyone who implies so. In fact corner balancing is not possible without after-market drop link to take away the pre load.
4. The cost for coilover install should not be much more than for lowering spring. Depends on tuner and location of course, but lowest rate for me FWIW was $850 (?? IIRC) for full coilover install 5 years ago in Los Angeles, including alignment. Nowadays, maybe 850-1200 is the range? But I doubt very much there is going to be a big difference between b8 and b16 install, and both will be not much more than lowering springs, within $200 I would think. This is the Porsche tax we talked about.
5. If you are the nutty type who wants to change springs
, b8 limits your choice to expensive lowering springs by vendor with unknown rates, b16 as a full coilover allows you full possibilities of any spring and any rate at about 100 or so each (can't remember how much I paid but it's dirt cheap).
1. Be careful with the springs you pick and select one per your taste (no right or wrong): GMG is stiffer, H&R is like stock, and Eibach I don't know. Very true the costs are different but the spring rates may not be all the same.
2. You can't adjust height with B8, unlike B16 Damptronic. With B8 your car will be lowered a fixed 24mm, with B16 Damptronic it's adjustable 5mm to 24mm. A consideration for those in big cities.
3. Corner balancing is not part of a coilover install - tuner should never charge you for that and run away from anyone who implies so. In fact corner balancing is not possible without after-market drop link to take away the pre load.
4. The cost for coilover install should not be much more than for lowering spring. Depends on tuner and location of course, but lowest rate for me FWIW was $850 (?? IIRC) for full coilover install 5 years ago in Los Angeles, including alignment. Nowadays, maybe 850-1200 is the range? But I doubt very much there is going to be a big difference between b8 and b16 install, and both will be not much more than lowering springs, within $200 I would think. This is the Porsche tax we talked about.
5. If you are the nutty type who wants to change springs
, b8 limits your choice to expensive lowering springs by vendor with unknown rates, b16 as a full coilover allows you full possibilities of any spring and any rate at about 100 or so each (can't remember how much I paid but it's dirt cheap).
Last edited by cannga; 07-01-2013 at 02:33 PM.
#22
07-01-2013, 05:12 PM
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I may go this route, eilbach makes the gmg springs, they also offer a stiffer tuv spring that only drops 15mm.
#23
07-01-2013, 08:17 PM
Just curious: what is it about the spring that makes it TUV?
#24
07-01-2013, 09:05 PM
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I think they can only lower within a certain range to be tuv, or a stock replacement.
Yes, I've done my homework
This is as close to an x73 for the 997tt as you can get. Yes, just as costly as coil overs.
Fvd has them on their site.
C
Yes, I've done my homework
This is as close to an x73 for the 997tt as you can get. Yes, just as costly as coil overs.
Fvd has them on their site.
C
#25
07-01-2013, 09:08 PM
I will be trying this exact setup soon
I personally think the gmg spring rates are ideal for use with an upgraded stiffer valved short body monotube shock like the bilstein sport.
I also like the simplicity of this setup relative to the bilstein damptronic coil with helper springs.
I will update in the coming weeks.
I personally think the gmg spring rates are ideal for use with an upgraded stiffer valved short body monotube shock like the bilstein sport.
I also like the simplicity of this setup relative to the bilstein damptronic coil with helper springs.
I will update in the coming weeks.
#26
07-01-2013, 09:13 PM
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#28
07-03-2013, 12:39 PM
As an update to this
I was able to secure a set of these. I will be tracking my car again next weekend at TWS with my current setup which is the following (will not have the shocks in for this track event)
-GMG springs / sways
-sway set to soft / medium (F/R)
-bridgestone re11 tires in stocks sizes
-lightweight forged breyton wheels 8.5/12
-PFC 08 brake pads with stock rotors
My current driving skill level is blue / blue solo depending on the organization. Still a rookie, but aware enough to evaluate the shocks.
My goal for adding the shocks is to control the rebound damping a little better, and for the suspension to settle quicker and more effectively. by doing this, I hope grip will increase on turn in and quick transitions, as well as on undulating pavement and camber changes. A side benefit is improved ride quality on the street.
Time will tell, and I will update everyone.
I will hopefully have the B8 damptronic shocks installed in a couple weeks and will test them during the next track weekend after this TWS event which will be at NOLA motorsports in a PCA event on July 28-29. Then another track weekend at TWS in mid august.
I was able to secure a set of these. I will be tracking my car again next weekend at TWS with my current setup which is the following (will not have the shocks in for this track event)
-GMG springs / sways
-sway set to soft / medium (F/R)
-bridgestone re11 tires in stocks sizes
-lightweight forged breyton wheels 8.5/12
-PFC 08 brake pads with stock rotors
My current driving skill level is blue / blue solo depending on the organization. Still a rookie, but aware enough to evaluate the shocks.
My goal for adding the shocks is to control the rebound damping a little better, and for the suspension to settle quicker and more effectively. by doing this, I hope grip will increase on turn in and quick transitions, as well as on undulating pavement and camber changes. A side benefit is improved ride quality on the street.
Time will tell, and I will update everyone.
I will hopefully have the B8 damptronic shocks installed in a couple weeks and will test them during the next track weekend after this TWS event which will be at NOLA motorsports in a PCA event on July 28-29. Then another track weekend at TWS in mid august.
