Seeking Suspension Improvement.
04-18-2018, 07:20 AM
#1
Seeking Suspension Improvement.
2006 AP2 Mostly Stock Car that is 80% track toy at this time.
- club racer pads/rs4 tires/rollbar; otherwise stock
- I am interested in improving suspension (less dive and pitch)
From what I've read Stock:
- Front: 262 lbs/in (4.7 kg/mm)
- REar: 269 lbs/in (4.8 kg/mm)
Has anyone TRACKED with Swift SPEC-R Sport Springs?
- Front (kg/mm): 7.5 (419 lbs/inch)
- Rear (kg/mm): 7 (391 lbs/inch)
- Front Drop: -30mm (-1.2 in)
- Rear Drop: -30mm (-1.2 in)
Is there anyone out here that has used the swift spring and improved lap times on stock shocks/dampeners
- I'm interested in performance not looks.
- Will drop in height require "roll center correction"?
- If no improvement I might as well just wait for coilovers....
- thinking about FA510 vs HKS SPs vs IDK...
- club racer pads/rs4 tires/rollbar; otherwise stock
- I am interested in improving suspension (less dive and pitch)
From what I've read Stock:
- Front: 262 lbs/in (4.7 kg/mm)
- REar: 269 lbs/in (4.8 kg/mm)
Has anyone TRACKED with Swift SPEC-R Sport Springs?
- Front (kg/mm): 7.5 (419 lbs/inch)
- Rear (kg/mm): 7 (391 lbs/inch)
- Front Drop: -30mm (-1.2 in)
- Rear Drop: -30mm (-1.2 in)
Is there anyone out here that has used the swift spring and improved lap times on stock shocks/dampeners
- I'm interested in performance not looks.
- Will drop in height require "roll center correction"?
- If no improvement I might as well just wait for coilovers....
- thinking about FA510 vs HKS SPs vs IDK...
04-18-2018, 10:26 AM
#2
Here's my own experience...
I went from a full 07 OEM set up to CR sway bars & CR shocks with the Swift Spec R springs. They lowered the car a good bit and looked impressive.
I also took that exact set up to Gridlife, and on 245/40-17 RE71Rs the car was flying. Podiumed at Gingerman behind a Corvette C5 and a S197 Mustang GT, and won Autobahn outright.
It was definitely better than stock, but there was still quite a bit of body roll and pitch. Most notably, Autobahn Country Club North Layout, T3-T4 transition. Once you load the car up going through the fast right, it takes a while for the car to get settled before you can turn in for the fast left that followed immediately. On one occasion I tried to do it a little too aggressively and ended up spinning off the track backwards. Similar issues at Gingerman T8-T9.
Depending on your driver skills, these could be a very effective upgrade from the stock shocks for sure, especially for a street-track hybrid. A larger front sway bar like the Whiteline 30mm bar can also be used to help bring body roll under control.
Eventually I outgrew that setup, but my old Tein Type Flex was barely an upgrade. I now have a set of custom-valved Stance XR1s, 14K springs at the front and 12K at the rear. Probably a little too harsh for the road but feels a lot nicer and more under control on track.
I went from a full 07 OEM set up to CR sway bars & CR shocks with the Swift Spec R springs. They lowered the car a good bit and looked impressive.
I also took that exact set up to Gridlife, and on 245/40-17 RE71Rs the car was flying. Podiumed at Gingerman behind a Corvette C5 and a S197 Mustang GT, and won Autobahn outright.
It was definitely better than stock, but there was still quite a bit of body roll and pitch. Most notably, Autobahn Country Club North Layout, T3-T4 transition. Once you load the car up going through the fast right, it takes a while for the car to get settled before you can turn in for the fast left that followed immediately. On one occasion I tried to do it a little too aggressively and ended up spinning off the track backwards. Similar issues at Gingerman T8-T9.
Depending on your driver skills, these could be a very effective upgrade from the stock shocks for sure, especially for a street-track hybrid. A larger front sway bar like the Whiteline 30mm bar can also be used to help bring body roll under control.
Eventually I outgrew that setup, but my old Tein Type Flex was barely an upgrade. I now have a set of custom-valved Stance XR1s, 14K springs at the front and 12K at the rear. Probably a little too harsh for the road but feels a lot nicer and more under control on track.
04-18-2018, 10:44 AM
#3
Hell just swapping in a 00-01 427lb front sway bar will be a very noticeable improvement! You need a stiffer front bar to keep the body roll down and the rear end glued. The stiffer spring rates all around will also help substantially, but first thing is to get the sway bar balance right, and its not right from the factory on your year s2k.
04-18-2018, 07:05 PM
#5
Determine first:
What is your budget? Both for the car and for running it for a year which will include brakes, tires, etc.
Do you plan to run in any competitive class that has rules? Rules often set the limits on what can be done, for example, wheel and tire size, aerodynamics, necessary safety equipment.
You seem to be looking at coil-overs which will include springs. You seem to be looking at coil-overs under $2000. Note that with the exception of the Bilstein PSS (which would need different springs and revalving to be a good track shocks) all the coil-over monotubes in that price range (considering a twin tube wouldn't be wise) are a common cartridge that is put into a lower shock mount. The OEM rear shocks and the Bilstein PSS have a piggyback reservoir to add travel in contrast with the cartridge shocks taking it away.
Most using coil-overs seem to run springs stiff enough that the anti-roll bar size isn't as critical. Some of that is to control pitch and dive with the S2k's short wheelbase. However, if running a bar going with one with replaceable torsion bars like the Karcepts would provide more tuning options.
The roll center adjusters reduce the angle of the lower arms when lowered, but not the upper. That should shorten the swing arm but maintain a higher roll center. In order to get enough negative camber, you will need offset ball joints. Some of the roll center adjusters combine an offset to increase the camber.
Adding brake cooling ducts and changing to rotors with more mass seem to be essential changes. Going to aftermarket calipers with larger diameter front rotors is a way to get there, but just changing the rotors, pads, and ducts are probably adequate.
BTW, did you mean rollbar and harness? You've already cut up the interior to fit the bar? Have you changed the seat?
,
What is your budget? Both for the car and for running it for a year which will include brakes, tires, etc.
Do you plan to run in any competitive class that has rules? Rules often set the limits on what can be done, for example, wheel and tire size, aerodynamics, necessary safety equipment.
You seem to be looking at coil-overs which will include springs. You seem to be looking at coil-overs under $2000. Note that with the exception of the Bilstein PSS (which would need different springs and revalving to be a good track shocks) all the coil-over monotubes in that price range (considering a twin tube wouldn't be wise) are a common cartridge that is put into a lower shock mount. The OEM rear shocks and the Bilstein PSS have a piggyback reservoir to add travel in contrast with the cartridge shocks taking it away.
Most using coil-overs seem to run springs stiff enough that the anti-roll bar size isn't as critical. Some of that is to control pitch and dive with the S2k's short wheelbase. However, if running a bar going with one with replaceable torsion bars like the Karcepts would provide more tuning options.
The roll center adjusters reduce the angle of the lower arms when lowered, but not the upper. That should shorten the swing arm but maintain a higher roll center. In order to get enough negative camber, you will need offset ball joints. Some of the roll center adjusters combine an offset to increase the camber.
Adding brake cooling ducts and changing to rotors with more mass seem to be essential changes. Going to aftermarket calipers with larger diameter front rotors is a way to get there, but just changing the rotors, pads, and ducts are probably adequate.
BTW, did you mean rollbar and harness? You've already cut up the interior to fit the bar? Have you changed the seat?
,
04-18-2018, 09:53 PM
#6
Hell just swapping in a 00-01 427lb front sway bar will be a very noticeable improvement! You need a stiffer front bar to keep the body roll down and the rear end glued. The stiffer spring rates all around will also help substantially, but first thing is to get the sway bar balance right, and its not right from the factory on your year s2k.
04-18-2018, 10:07 PM
#7
^^^Oops you got me, Punk! 
Sudden laps in memory.
Let me revise my recommendation. Get the 00-01 393lb front sway swapped in.
Now go bug your wife, we got a concert to attend!
Ps, I'm going to join up on the Lotus forum so I can monitor the opinion pieces going on over there
Sudden laps in memory.Let me revise my recommendation. Get the 00-01 393lb front sway swapped in.
Now go bug your wife, we got a concert to attend!
Ps, I'm going to join up on the Lotus forum so I can monitor the opinion pieces going on over there
Last edited by s2000Junky; 04-18-2018 at 10:25 PM.
Trending Topics
04-20-2018, 12:43 PM
#8
Determine first:
What is your budget? Both for the car and for running it for a year which will include brakes, tires, etc.
Do you plan to run in any competitive class that has rules? Rules often set the limits on what can be done, for example, wheel and tire size, aerodynamics, necessary safety equipment.
You seem to be looking at coil-overs which will include springs. You seem to be looking at coil-overs under $2000. Note that with the exception of the Bilstein PSS (which would need different springs and revalving to be a good track shocks) all the coil-over monotubes in that price range (considering a twin tube wouldn't be wise) are a common cartridge that is put into a lower shock mount. The OEM rear shocks and the Bilstein PSS have a piggyback reservoir to add travel in contrast with the cartridge shocks taking it away.
Most using coil-overs seem to run springs stiff enough that the anti-roll bar size isn't as critical. Some of that is to control pitch and dive with the S2k's short wheelbase. However, if running a bar going with one with replaceable torsion bars like the Karcepts would provide more tuning options.
The roll center adjusters reduce the angle of the lower arms when lowered, but not the upper. That should shorten the swing arm but maintain a higher roll center. In order to get enough negative camber, you will need offset ball joints. Some of the roll center adjusters combine an offset to increase the camber.
Adding brake cooling ducts and changing to rotors with more mass seem to be essential changes. Going to aftermarket calipers with larger diameter front rotors is a way to get there, but just changing the rotors, pads, and ducts are probably adequate.
BTW, did you mean rollbar and harness? You've already cut up the interior to fit the bar? Have you changed the seat?
,
What is your budget? Both for the car and for running it for a year which will include brakes, tires, etc.
Do you plan to run in any competitive class that has rules? Rules often set the limits on what can be done, for example, wheel and tire size, aerodynamics, necessary safety equipment.
You seem to be looking at coil-overs which will include springs. You seem to be looking at coil-overs under $2000. Note that with the exception of the Bilstein PSS (which would need different springs and revalving to be a good track shocks) all the coil-over monotubes in that price range (considering a twin tube wouldn't be wise) are a common cartridge that is put into a lower shock mount. The OEM rear shocks and the Bilstein PSS have a piggyback reservoir to add travel in contrast with the cartridge shocks taking it away.
Most using coil-overs seem to run springs stiff enough that the anti-roll bar size isn't as critical. Some of that is to control pitch and dive with the S2k's short wheelbase. However, if running a bar going with one with replaceable torsion bars like the Karcepts would provide more tuning options.
The roll center adjusters reduce the angle of the lower arms when lowered, but not the upper. That should shorten the swing arm but maintain a higher roll center. In order to get enough negative camber, you will need offset ball joints. Some of the roll center adjusters combine an offset to increase the camber.
Adding brake cooling ducts and changing to rotors with more mass seem to be essential changes. Going to aftermarket calipers with larger diameter front rotors is a way to get there, but just changing the rotors, pads, and ducts are probably adequate.
BTW, did you mean rollbar and harness? You've already cut up the interior to fit the bar? Have you changed the seat?
,
- The car is used/will be used for track days ~ 20 days per year plus the occasional weekend drives
- The car is only being used in DE's/lapping days so no SPEC to abide too
- My goal is really to just get better/faster
- Roll bar is in, I use a hard top, I have the BYS rails installed (and removed ~ 1 inch of foam from the seat bottom)
- You're correct in that I am looking at coil-overs, but I would be satisfied (for now) with the springs if I get 80% of what a nice set of coil-overs would get me
- You mention that sub 2k are sub-optimal, then what do you consider optimal?
Last edited by auric; 04-20-2018 at 01:01 PM.
04-20-2018, 01:43 PM
#9
Something I would consider that will be useful now and in the future if ever you upgrade to coil overs are roll center adjusters.
It's more important now on the non-adjustable OEM shocks that were engineered and designed for a specific suspension geometry and ride height. Lowering the car with springs only will affect both of those items negatively.
You can do the J's racing type of ball joint up front and add in the roll center plate. It also has the added benefit of giving you more adjustable camber to get in to the -3.0 range which is what the s2k really needs up front for all of the best summer tires.
Manufactures include:
-J's (S1 or S2)
-EVS - evasive makes one now
-Hardrace
-Megan racing
The rear is just an RCA alone, full ball joint replacement that requires a press to remove and install.
They're not necessary, but they are a part that will benefit you overall for lowering the car. it corrects the suspension geometry change whether on lowering springs or coil overs. Do you have to do it? No. Does it affect things? Probably (at least in a theoretical, engineering, mathematical model sort of way). Has anyone tested a before and after of RCAs only (no other modifications or suspension changes) with/without - probably not. Does it shave seconds off of laptimes? Doubtful.
It's more important now on the non-adjustable OEM shocks that were engineered and designed for a specific suspension geometry and ride height. Lowering the car with springs only will affect both of those items negatively.
You can do the J's racing type of ball joint up front and add in the roll center plate. It also has the added benefit of giving you more adjustable camber to get in to the -3.0 range which is what the s2k really needs up front for all of the best summer tires.
Manufactures include:
-J's (S1 or S2)
-EVS - evasive makes one now
-Hardrace
-Megan racing
The rear is just an RCA alone, full ball joint replacement that requires a press to remove and install.
They're not necessary, but they are a part that will benefit you overall for lowering the car. it corrects the suspension geometry change whether on lowering springs or coil overs. Do you have to do it? No. Does it affect things? Probably (at least in a theoretical, engineering, mathematical model sort of way). Has anyone tested a before and after of RCAs only (no other modifications or suspension changes) with/without - probably not. Does it shave seconds off of laptimes? Doubtful.
04-20-2018, 02:54 PM
#10
- Bull thanks for the advice.
- I've purchased the Megan Racing kit
- The question that remains is whether I go Swift Spec-R or Sub 2K coilover (like the HKS 4 SP)
- How much better is the sub 2K coilover on track?
- I've purchased the Megan Racing kit
- The question that remains is whether I go Swift Spec-R or Sub 2K coilover (like the HKS 4 SP)
- How much better is the sub 2K coilover on track?
