Track Day Suspension Questions...
02-23-2009, 08:09 PM
#11
2nd Gear Member
Join Date: Dec 2006
Location: Flanders, NJ
Posts: 408
Tires and Brakes will be your best upgrades. Everything you stated is about what the car does, just the handling characteristics of these mustangs. I never tracked my car on the stock dampers but I did autocross it before I put the Koni Yellows in. I never felt the rear end get twichy, unless I was being careless, on the Koni's but like Brad said, I have done the same; learn to drive around it. A good set of R-Comps will take you a long way, RA-1, NT01, R888 are all very good track tires for a reasonable price. An alignment will help also, -2.0 deg camber you can get out of your stock suspension with out camber plates. That will help take out the the vague feeling out of the steering, I also have Sam Strano's adjustable front sway bar end links.
02-24-2009, 12:19 AM
#12
5th Gear Member
Join Date: May 2007
Location: Central Texas
Posts: 2,388
Hey Steve! I thought you car was already modified in the suspension dept, I was gonna talk to you at the mall, but we hit the road and then I forgot.
I too enjoyed the cruise...hell I'm still grinning about it!...
I recently put in Steeda springs and Tociko D-specs and it made a big difference in the cornering and handling, while lowering the car only about an inch up front and 1.25" at the back. But I also have numerous other suspension parts that all help here and there as listed in my sig. Without them there's no way I could have driven that route we drove at the [legal] speeds we were driving.
DAMN THAT WAS FUUUUUUUUUUUUUUNNNNNNNN
I too enjoyed the cruise...hell I'm still grinning about it!...
I recently put in Steeda springs and Tociko D-specs and it made a big difference in the cornering and handling, while lowering the car only about an inch up front and 1.25" at the back. But I also have numerous other suspension parts that all help here and there as listed in my sig. Without them there's no way I could have driven that route we drove at the [legal] speeds we were driving.
DAMN THAT WAS FUUUUUUUUUUUUUUNNNNNNNN
02-24-2009, 01:25 PM
#13
Former Sponsor
Join Date: Sep 2007
Posts: 1,936
I come to all you handling gurus for some advice!!
After spending most of Saturday blitzing the back roads around Austin and Marble Falls I’ve found a few shortcomings with the Mustang that I’d like to address if possible. I realize the car will never really be considered ‘nimble’ but I’d like to improve some aspects of the handling.
I’ve raced sportbikes on the track for several years so I’ll try to translate the lingo into car talk... :-)
1. So when I’m going into a corner a briskly (I’m on stock tires and suspension) I can feel the front end push a little bit. The turn in seems a bit vague, not as direct as I’d like it to be.
2. Once I get the car into the corner it seems to settle in and track quite well. However very minor steering corrections seem to unsettle the chassis rather easily. Also, bumps in the middle of the corner are never good, but the GT seems to ‘wallow’ or ‘jostle’ around the rear end when hitting a small dip or raise mid-corner.
3. On corner exits the car was great actually. I was able to do a little rear-wheel steering in some of the corner exits, but it certainly isn’t the fastest way around the corner. :-) I would like to be able to put the power down a little better as I tended to get some unexpected wheel spin a few times.
All in all, I was surprised with how well our “muscle car” performed in the twisties. I did definitely go a bit faster than is prudent on public roads, but I was always well within my comfort range. The nice thing is that I know the car has more potential when on the track.
I also found that this car seems to likes a more swooping arc around corners. I tried the slow in, fast out approach and that was fun… also the fast in, (brake hard) and fast out approach but that really seemed to unsettle the rear end and to be honest, I don’t like going fast into the corners on the public roads… lastly I just tried to set my speed at the start of the corner and then carry it all the way through and then accelerate out.
So, now that I’ve written a book on my impressions (sorry, no cliff notes) I’m looking for advice on what would be the best route for me to take suspension wise. This is my daily driver, but I’m going to start doing some trackdays around here and would really like to improve the handling some. Since it will be my DD, I don’t want anything hard core suspension wise or anything too pricey. Also, I can’t do it all at once… I’ll have to pace myself with these mods.
I know better tires will help, but I’m looking more for actual suspension bits… on my old racebike I dropped 6 seconds off my time at Texas World Speedway (and 4 at MSR Cresson) when I swapped to a high performance shock and fork internals. I’m hoping to be able to feel similar improvements with the car!
Any advice you all can provide would be much appreciated!!
After spending most of Saturday blitzing the back roads around Austin and Marble Falls I’ve found a few shortcomings with the Mustang that I’d like to address if possible. I realize the car will never really be considered ‘nimble’ but I’d like to improve some aspects of the handling.
I’ve raced sportbikes on the track for several years so I’ll try to translate the lingo into car talk... :-)
1. So when I’m going into a corner a briskly (I’m on stock tires and suspension) I can feel the front end push a little bit. The turn in seems a bit vague, not as direct as I’d like it to be.
2. Once I get the car into the corner it seems to settle in and track quite well. However very minor steering corrections seem to unsettle the chassis rather easily. Also, bumps in the middle of the corner are never good, but the GT seems to ‘wallow’ or ‘jostle’ around the rear end when hitting a small dip or raise mid-corner.
3. On corner exits the car was great actually. I was able to do a little rear-wheel steering in some of the corner exits, but it certainly isn’t the fastest way around the corner. :-) I would like to be able to put the power down a little better as I tended to get some unexpected wheel spin a few times.
All in all, I was surprised with how well our “muscle car” performed in the twisties. I did definitely go a bit faster than is prudent on public roads, but I was always well within my comfort range. The nice thing is that I know the car has more potential when on the track.
I also found that this car seems to likes a more swooping arc around corners. I tried the slow in, fast out approach and that was fun… also the fast in, (brake hard) and fast out approach but that really seemed to unsettle the rear end and to be honest, I don’t like going fast into the corners on the public roads… lastly I just tried to set my speed at the start of the corner and then carry it all the way through and then accelerate out.
So, now that I’ve written a book on my impressions (sorry, no cliff notes) I’m looking for advice on what would be the best route for me to take suspension wise. This is my daily driver, but I’m going to start doing some trackdays around here and would really like to improve the handling some. Since it will be my DD, I don’t want anything hard core suspension wise or anything too pricey. Also, I can’t do it all at once… I’ll have to pace myself with these mods.
I know better tires will help, but I’m looking more for actual suspension bits… on my old racebike I dropped 6 seconds off my time at Texas World Speedway (and 4 at MSR Cresson) when I swapped to a high performance shock and fork internals. I’m hoping to be able to feel similar improvements with the car!
Any advice you all can provide would be much appreciated!!
Your background will be a help to understanding things.
First, let me say that part of the complaint #1, all of #2 and part of #3 are damper related and that's ABSOLUTELY where I'd start. I say this not only based on theory, but on what I've done with results to prove it.
Better dampers will do the following: Give you more crisp turn in response. Settle the back end's tendency to jump around so much way down. The car will take a set much better and more quickly, the wobbly feel is the fact the car is not taking a set because the mass is not being damped and wants to continue to wiggle around. I'll pull no punches here, I certainly prefer Koni over D-specs and right now it's nice that Koni's are on sale for $700 shipped.....
The other thing I'd do is change the alignment to enhance the front end grip (read more negative camber). We can do this a number of ways from different upper mounts/camber plates to some Ford or aftermarket camber bolts (aftermarket cheapies being my least favorite choice as they are more prone to slipping).
Those are the first recommended mods, and we reassess from there. Sure you can do springs, change bars, and add about a million other available parts. But based on your debreifing (which I might add is on of the better, on point break downs I've seen in while), it's clear to me we need to work the dampers.
02-24-2009, 07:36 PM
#14
1st Gear Member
Join Date: Dec 2007
Posts: 100
I know it's been said here a couple times, but probably not emphatic enough. If you want to drive the car at track days, deal with the brakes first. Any other modification would likely only send you into the braking zone even faster than the stock suspension and tires. I didn't even bother taking my stock GT to the track without pads (Hawk HP+), stainless lines and high-temp fluid based upon what I read here.
That said, having some background in driving (karting, race schools, autocross, etc.) I quickly found the limits of this setup and before my very next track event needed to add brake ducts and the Hawk Blue pads. It's no fun nursing inadequate brakes around a road course. Given that you've done track events on a bike, I'd say you may be pushing the car to the limits sooner than somebody without that experience.
It doesn't mean you can't take it easy on the brakes when doing such things, it's just much easier to keep up with other cars in your run group if your brakes inspire confidence. I do understand that using brake ducts on a daily driver might not be ideal, I just offer my experience so that at least if you do have brake issues, they won't be unexpected.
FWIW, if I had to have a setup that would pull double duty for street and track I would probably use the biggest brake discs I could find for the front in order to increase my heat sink and dissipation capacity as much as possible.
Beyond brakes, I will echo much of the other comment: tires, camber, dampers and, if you want more neutral handling in steady-state turns, a rear sway bar.
That said, having some background in driving (karting, race schools, autocross, etc.) I quickly found the limits of this setup and before my very next track event needed to add brake ducts and the Hawk Blue pads. It's no fun nursing inadequate brakes around a road course. Given that you've done track events on a bike, I'd say you may be pushing the car to the limits sooner than somebody without that experience.
It doesn't mean you can't take it easy on the brakes when doing such things, it's just much easier to keep up with other cars in your run group if your brakes inspire confidence. I do understand that using brake ducts on a daily driver might not be ideal, I just offer my experience so that at least if you do have brake issues, they won't be unexpected.
FWIW, if I had to have a setup that would pull double duty for street and track I would probably use the biggest brake discs I could find for the front in order to increase my heat sink and dissipation capacity as much as possible.
Beyond brakes, I will echo much of the other comment: tires, camber, dampers and, if you want more neutral handling in steady-state turns, a rear sway bar.
02-25-2009, 07:43 PM
#15
Join Date: Mar 2006
Posts: 13
ESP - Dampers? What else?
That said, I run ESP and would like to look at the next step for what to do with the car.
If Koni yellows are the way to go, how do I know how to adjust them? My ***-o-meter isn't all that refined, so there's a danger I'd screw up the adjustments. Is it pretty straightforward? Are the Koni's a bunch better than the multimatic FRPP dampers?
Any other car mods which are high bang-for-the-buck for ESP?
I've ran about 12 events last year, had a 2 day Evo school, will be going to the StLoius Evo school in a few weeks......so the loose nut behind the wheel is hopefully getting better.
Jim
02-25-2009, 08:21 PM
#16
4th Gear Member
Thread Starter
Join Date: Dec 2007
Location: TEXAS
Posts: 1,491
All, thanks for the advice. There really is a wealth of knowledge here and I appreciate your responses!
I think I'm going to go the route of new/better dampers as it sounds like they will have the biggest initial impact on performance. I'll have to do some more research into which one is going to be best for me: Koni or Tokico.
One question though, with the dampers can I run the stock springs and still gain the performance advantage or would it be best if I upgraded the springs at the same time and got some camber plates to round things out?
tx_zstang... unfortunately my suspension is still stock and it got one heck of a workout this weekend. On our way back me and the orange 2002 GT, and the two hellion turbo'd 2007 GTs went back down 1431 alone. We definitely wicked up the pace and had an absolute blast. I didn't realize your car was a V6 until I saw your signature, it sounds like an 8 when you're just cruising around!
I think I'm going to go the route of new/better dampers as it sounds like they will have the biggest initial impact on performance. I'll have to do some more research into which one is going to be best for me: Koni or Tokico.
One question though, with the dampers can I run the stock springs and still gain the performance advantage or would it be best if I upgraded the springs at the same time and got some camber plates to round things out?
tx_zstang... unfortunately my suspension is still stock and it got one heck of a workout this weekend. On our way back me and the orange 2002 GT, and the two hellion turbo'd 2007 GTs went back down 1431 alone. We definitely wicked up the pace and had an absolute blast. I didn't realize your car was a V6 until I saw your signature, it sounds like an 8 when you're just cruising around!
02-25-2009, 10:37 PM
#17
2nd Gear Member
Join Date: Feb 2007
Location: Texas
Posts: 162
I've also been told that it's not such a bad thing to experience brake fade, but since you raced bikes you probably don't need that particular lesson.
- Wayne
02-25-2009, 10:54 PM
#18
4th Gear Member
Thread Starter
Join Date: Dec 2007
Location: TEXAS
Posts: 1,491
I've been told, again and again, to make one change at a time. And as Sam Strano finally drummed into my head, try different settings on the dampers before you go out and buy the next new part.
I've also been told that it's not such a bad thing to experience brake fade, but since you raced bikes you probably don't need that particular lesson.
- Wayne
I've also been told that it's not such a bad thing to experience brake fade, but since you raced bikes you probably don't need that particular lesson.
- Wayne
02-25-2009, 11:04 PM
#19
5th Gear Member
Join Date: May 2007
Location: Central Texas
Posts: 2,388
On our way back me and the orange 2002 GT, and the two hellion turbo'd 2007 GTs went back down 1431 alone. We definitely wicked up the pace and had an absolute blast. I didn't realize your car was a V6 until I saw your signature, it sounds like an 8 when you're just cruising around!
Thanks for the feedback on sound; I have no idea what she sounds like from behind. There were some great sounding cars out there.
02-26-2009, 07:04 AM
#20
6th Gear Member
Join Date: Feb 2007
Location: state of confusion
Posts: 7,635
Originally Posted by http://www.salug.org/~davidm/cars/koni.html
Adjusting the REBOUND Damping Control
Once you have found what you feel to be the best bump setting on all four wheels, you are now ready to proceed with adjusting the rebound. The rebound damping controls the transitional roll (lean) as when entering a turn. It does *not* limit the total amount of roll; it *does* limit how *fast* this total roll angle is achieved. How much the vehicle actually leans is determined by other things such as spring rate, sway bars, roll center, ride heights, etc.
It should be noted that too much rebound on either end of the vehicle will cause an initial loss of lateral acceleration (cornering grip) a that end which will cause the vehicle to oversteer or understeer excessively when entering a turn. Too much rebound control in relation to spring rate will cause a condition known as "jacking down." This is a condition where, after hitting a bump and compressing the spring, the damper does not allow the spring to return to a neutral position before the next bump is encountered. This repeats with each subsequent bump until the car is actually lowered onto the bump stops. Contact with the bump stops causes a drastic increase in roll stiffness. If this condition occurs on the front, the car will understeer; if it occurs on the rear, the car will oversteer.
STEP 1: With rebound set on full soft and the bump control set from your earlier testing, drive the car one of two laps, paying particular attention to how the car rolls when entering a turn.
STEP 2: Increase rebound damping three sweeps (or 3/4 turn) on all four dampers and drive the car one or two laps. Repeat Step 2 until the car enters the turns smoothly (no drastic attitude changes) and without leaning excessively. An increase in the rebound stiffness beyond this point is unnecessary and may result in a loss of cornering power. Note: As with the bump settings, this point will probably be reached at one end of the car before the other.
However, individual drivers may find it desirable to have a car that assumes an oversteering or understeering attitude when entering a turn. This can be easily "dialed-in" using slightly excessive rebound settings at either end.
Once you have found what you feel to be the best bump setting on all four wheels, you are now ready to proceed with adjusting the rebound. The rebound damping controls the transitional roll (lean) as when entering a turn. It does *not* limit the total amount of roll; it *does* limit how *fast* this total roll angle is achieved. How much the vehicle actually leans is determined by other things such as spring rate, sway bars, roll center, ride heights, etc.
It should be noted that too much rebound on either end of the vehicle will cause an initial loss of lateral acceleration (cornering grip) a that end which will cause the vehicle to oversteer or understeer excessively when entering a turn. Too much rebound control in relation to spring rate will cause a condition known as "jacking down." This is a condition where, after hitting a bump and compressing the spring, the damper does not allow the spring to return to a neutral position before the next bump is encountered. This repeats with each subsequent bump until the car is actually lowered onto the bump stops. Contact with the bump stops causes a drastic increase in roll stiffness. If this condition occurs on the front, the car will understeer; if it occurs on the rear, the car will oversteer.
STEP 1: With rebound set on full soft and the bump control set from your earlier testing, drive the car one of two laps, paying particular attention to how the car rolls when entering a turn.
STEP 2: Increase rebound damping three sweeps (or 3/4 turn) on all four dampers and drive the car one or two laps. Repeat Step 2 until the car enters the turns smoothly (no drastic attitude changes) and without leaning excessively. An increase in the rebound stiffness beyond this point is unnecessary and may result in a loss of cornering power. Note: As with the bump settings, this point will probably be reached at one end of the car before the other.
However, individual drivers may find it desirable to have a car that assumes an oversteering or understeering attitude when entering a turn. This can be easily "dialed-in" using slightly excessive rebound settings at either end.
Norm
Last edited by Norm Peterson; 02-26-2009 at 07:07 AM.