Suspension gurus. Need advice on setup.

[BuickGN]

I've got a group of people from work going to Willow Springs in the next couple months and I was invited. My TL was stock for many miles but I started the upgrades immediately after the talk of Willow a year ago.

So far here's what I have.....

Koni Yellow shocks with adjustable rebound.
Factory A-spec springs (maybe 20% stiffer than stock, barely noticable)
24mm rear swaybar that's adjustable
28mm front swaybar that's adjustable
255/40 high performance summer tires on stock 17" rims.

I know I need more spring but this is a daily driver semi-luxury car so I'm not willing to go any further on spring rates. That's why I compromised with larger swaybars than I would normally get. I realize too big is a problem but since this is a daily driven car I figure the compromise is worth it.

Right now handling is pretty balanced. It has slight understeer wtih my foot barely on the throttle and will rotate the tail if I lift.

I have some 13" Wilwoods on the way. Engine mods are not an option.

I'm not sure what else to do besides going with some stickier tires which is very likely. I need to compete with some co-worker's BMWs, a Cayenne, Cayman, WRX, and a Scion. I'm a bit worried about the Cayman but the owner is not a car guy and I'm hoping I can out drive him. It's very hard for me to get used to this FWD platform, it goes against everything I've learned over the years. I have to think about what to do when it slides rather than it being natural like the GN. Maybe some practice will help. These guys are some of the biggest trash talkers and I would never hear the end of it if I didn't place well.

 

[np6000]

I know you wanted to know about suspension, but what brakes planning to run? Spring for the race fluid and maybe a set of track rotors and pads that are dedicated for track use.

Two laps of hard driving will make pedal fade an unwanted friend.

Sticky tires will also make for a huge improvement in your lap times. No matter how sticky you think your high perf. summers are, they probably aren't up to the task of full out track driving.

I learned all of the above the hard way.

 

[BuickGN]

Originally Posted By: np6000
I know you wanted to know about suspension, but what brakes planning to run? Spring for the race fluid and maybe a set of track rotors and pads that are dedicated for track use.

Two laps of hard driving will make pedal fade an unwanted friend.

Sticky tires will also make for a huge improvement in your lap times. No matter how sticky you think your high perf. summers are, they probably aren't up to the task of full out track driving.

I learned all of the above the hard way.



I could probably get away with some R compunds and the people I'm going with would never know.

I have some 13" Wilwoods that are supposed to fit under the stock 17" rims on the way. I'm going with DOT 5.1 fluid because I've found the ABS doesn't seem to hinder performance as bad with the thinner fluid. With DOT 3 it seems like ABS is way too conservative. I may even go so far as to pull the ABS fuse at the track.

 

[tom slick]

Are you running on the Streets of Willow or the International track? It'll make a big difference in setup. The "Streets" are somewhat flat and tight. The International track is long with a few long sweepers and elevation changes, very very fast speeds.

 

[IndyIan]

Sounds like you've got all the weapons, the biggest bang for the buck is to get some sticky tires and run some autocross events atleast. Especially if the other guys have sticky tires you'll need some to be somewhere close and some track time will help you get your sway bars and shocks adjusted in the ball park atleast.
Which track are you going on? With the adjustable sway bars and shocks I'd watch you don't get the car too loose especially if you're on the big track. Worrying about swapping ends doesn't help your entry speeds... If you're on the tighter courses then you can have a more aggresive setup.
Track time will help you the most though, pratice throwing the back end out and gassing to save it, trail braking into a corner etc... I assume your car has all the electronic stabilty stuff too so figure out if it kills your speed or is your guardian angel... For solo 2 everyone at my club turns it all off, some even disable the ABS but its lower speed stuff.
Also you could adjust the camber abit, I run about -1.5 on the front with very little effect on the street.

I'd be tempted to run the buick if your on the smaller courses, with sticky tires it could be fun.

 

[BuickGN]

Originally Posted By: IndyIan
Sounds like you've got all weapons, the biggest bang for the buck is to get some sticky tires and run some autocross events atleast. Especially if the other guys have sticky tires you'll need some to be somewhere close and some track time will help you get your sway bars and shocks adjusted in the ball park atleast.
Which track are you going on? With the adjustable sway bars and shocks I'd watch you don't get the car too loose especially if you're on the big track. Worrying about swapping ends doesn't help your entry speeds... If you're on the tighter courses then you can have a more aggresive setup.
Track time will help you the most though, pratice throwing the back end out and gassing to save it, trail braking into a corner etc... I assume your car has all the electronic stabilty stuff too so figure out if it kills your speed or is your guardian angel... For solo 2 everyone at my club turns it all off, some even disable the ABS but its lower speed stuff.
Also you could adjust the camber abit, I run about -1.5 on the front with very little effect on the street.



Thank you. I'm not sure which course, I'm hoping for the lower speed course because my car is somewhat lacking in the power department.

My stability control isn't that intrusive. It will let the rear come out a few degrees before doing anything. The ABS is what I hate. It's as if it can't take advantage of the better tires. I beat the ABS by nearly 20' from 60mph over 5 stops with the fuse pulled.

I'm not worried about spinning, I think I've driven sideways as much as I've driven in a straight line lol, but I know the tail hanging out isn't the fastest way around a course.

Right now I have the shocks and swaybars in the soft settings and I plan to adjust in small increments from there. I just tried a neighborhood (20-55mph corners)that never got finished so it's nothing but streets, no houses, people, or cars, and the car definately pushes on anything but lifting thottle and even then it makes it somewhat neutral. I may go a step firmer on the rear bar this afternoon.

One question I have, adjusting the front shocks, will firmer typically reduce or increase understeer? After the front swaybar installation last night I feel that it needs a little more rebound damping. Before the front bar upgrade this car was very tail happy. One of the few FWD cars that I could regularly take a corner with the tail out. It's no wonder with a 24mm solid in the rear and a stock 25mm hollow up front.

Any opinions on swaybars vs springs to get the desired result? I know the disadvantages of too large of a swaybar on either end and so far I have no trouble putting the power down coming out of a corner but that may be because there's only 198hp at the wheels. Even though I'm not going any stiffer on the springs, do you think I'm losing a lot of performance going with the stiffer bar/softer spring route?

It's funny you mention -1.5 degrees of camber. Mine is not adjustable stock and with the slight lowering of the a-spec springs, I have -1.5 in front and -1.7 in the rear. Maybe I got lucky??

Thanks everyone for all the help.

 

[BuickGN]

Whoa, just saw the Mustang. So it is sliding to the right with a slight steering correction?

I've run the Buick at a couple autocrosses. It does surprisingly well but I have to manhandle it and get very good at predicting when the turbo is going to come online or it's 150hp to 600hp in a matter of a second. Quite honestly, I would love to take it on some of the high speed courses but the brakes would be gone before the first lap was over. Besides, I would have to turn the boost down, probably in the 450rwhp level to make it reliable for an all day event.

That car has much more extensive suspension mods. Tubular upper control arms, balljoint relocation kit to change the instant center, the typical springs and shocks all the way around, upper and lower control arm bushings replaced with bearings, 1.5" front bar, 1 5/8" rear bar, billet aluminum lower control arms, boxed stock uppers, tons of frame and body bracing, c-clip eliminators, Eaton posi, quicker steering ratio, etc. It feels like it outcorners the TL and it's 400lbs lighter so it may.

 

[IndyIan]

Originally Posted By: BuickGN
Whoa, just saw the Mustang. So it is sliding to the right with a slight steering correction?

That's how I see it too from the rubber on the pavement, looks like alot of fun! I imagine your TL might be lifting the inside rear on corner entry if you get R compounds. It will be interesting to see how well a heavy fwd car does with all the goodies on it. I have to say I've never really seen one on the track.
Originally Posted By: BuickGN

I've run the Buick at a couple autocrosses. It does surprisingly well but I have to manhandle it and get very good at predicting when the turbo is going to come online or it's 150hp to 600hp in a matter of a second. Quite honestly, I would love to take it on some of the high speed courses but the brakes would be gone before the first lap was over. Besides, I would have to turn the boost down, probably in the 450rwhp level to make it reliable for an all day event.

Here's a video to get your racing juices flowing, A Buick V6 Datsun leaving a Viper ACR at Mosport... http://www.youtube.com/watch?v=1KPxGxUiyoQ


As for the TL shock settings, my basic understanding is that making the front relatively stiffer promotes understeer, rear relatively stiffer promotes oversteer.
If its your first time on a fast track with the TL I'd start with the front bar stiff as possible, front shocks full stiff too, and the rear bar and shocks almost on full soft or where you think the car will understeer abit. Then start making the back stiffer to get a more neutral balance, if the car still plows with the back at full stiff then you could start backing off the front bar a little. You can play with tire pressures too, harder acts like stiffer springs, so you may end up with the back tires much harder than the fronts.
Anyways you probably won't find the perfect setup the first day out, take notes to remember what worked and what didn't.
Sounds like a fun day though.
Ian

 

[BuickGN]

Nice! We have a 4.1 Buick turbo V6 made of spare parts we've accumulated over the years getting ready to drop into a 71 Opel GT. Had the car weighed minus the engine at 1,800lbs and it made nearly 600hp on the engine dyno with a mild tune that we can run flat out all day. Should be fun.

Tried the car again today, definately going stiffer on the rear bar. It understeers almost like stock with the new front bar. I need to find out which track we're going to be on before I decide to dial out too much understeer but as of now it's pretty bad.

 

[AdRock]

Personally I find it much easier to control oversteer than understeer. If you want some brakes that will not fade hardly at all throw some cryo treated rotors and some of the Hawk racing pads on when you switch to the wilwood setup.

As far as the tires go, I've got some friends that do road track days & autocross and they've been happy with the new Nitto NT01 that came out recently.

If you want something for daily driving I've talked to people that seem to like the NT05 street tire. I've been thinking about trying some of those out myself.

 

[BuickGN]

Originally Posted By: AdRock
Personally I find it much easier to control oversteer than understeer. If you want some brakes that will not fade hardly at all throw some cryo treated rotors and some of the Hawk racing pads on when you switch to the wilwood setup.

As far as the tires go, I've got some friends that do road track days & autocross and they've been happy with the new Nitto NT01 that came out recently.

If you want something for daily driving I've talked to people that seem to like the NT05 street tire. I've been thinking about trying some of those out myself.


Same here, understeer scares me because there's not much you can do once it starts. Oversteer is recoverable in 90% of the situations.

I'll give those Nittos a look. Right now for a street tire I had my eye on the Dunlop Durezza Sport star spec. My car is very sensitive to road/tire noise and unfortunatly I have to take that into consideration.

 

[XS650]

Originally Posted By: AdRock
Personally I find it much easier to control oversteer than understeer.


Definitions:

Oversteer: When one end of the car breaks loose and the passenger is scarred.

Understeer: When one end of the car breaks loose and the driver is scared.

Or run ubber stiff rear sway bars on a FWD and experience both in the same corner

 

[BuickGN]

Originally Posted By: AdRock
Personally I find it much easier to control oversteer than understeer. If you want some brakes that will not fade hardly at all throw some cryo treated rotors and some of the Hawk racing pads on when you switch to the wilwood setup.

As far as the tires go, I've got some friends that do road track days & autocross and they've been happy with the new Nitto NT01 that came out recently.

If you want something for daily driving I've talked to people that seem to like the NT05 street tire. I've been thinking about trying some of those out myself.


I looked at those Nittos and I'm so glad I did. Even the street version looks very aggressive and it looks like it would be fairly quiet too. I'm not one to consider looks at all when buying tires but those things are pretty. On top of that, they're cheap.

Besides the obvious wear, is there any problem with running the race tires as a daily tire such as heat buildup on freeway trips?

The car is handling awesome. I went one step firmer on the rear bar and there's a hint of understeer at the limit but it's not bad at all. I'm very impressed with the difference in handling with a minimal change in comfort. Now I'm trying to wear these BFGs out so I don't feel guilty for buying the Nittos with half the tread left on my old tires.

 

[Shannow]

I'd pick a different employer...this lot seems way too competitive.

Just go slicks, nitrous, and load up on sodium before the race

 

[IndyIan]

Originally Posted By: Shannow
I'd pick a different employer...this lot seems way too competitive.

Just go slicks, nitrous, and load up on sodium before the race

LOL, it does seem a bit competitive for a "fun" track day... I'm waiting to hear that the guy with the Scion is a top notch driver and brought a set of hoosier autocross tires and smoked them all... For a lap or two anyways...

 

[BuickGN]

Originally Posted By: Shannow
I'd pick a different employer...this lot seems way too competitive.

Just go slicks, nitrous, and load up on sodium before the race


It's going to be a fun event. Most of these guys are not car guys, they just make a lot of money and wanted something pretty and shiny. I seem to get a lot more heat than the others, mostly because they're all friends that go home and game after work and I'm the resident power lifter so they're always trying to one up me in a friendly way. Maybe I came across as too competitive.

Although I considered a small 35-50 shot to help even things out but this is my daily driver so I decided against it.

 

[BuickGN]

Originally Posted By: IndyIan
Originally Posted By: Shannow
I'd pick a different employer...this lot seems way too competitive.

Just go slicks, nitrous, and load up on sodium before the race

LOL, it does seem a bit competitive for a "fun" track day... I'm waiting to hear that the guy with the Scion is a top notch driver and brought a set of hoosier autocross tires and smoked them all... For a lap or two anyways...



That has crossed my mind numerous times lol. Geting beat by a Porsche is ok. A Scion would hurt.

 

[IndyIan]

Originally Posted By: BuickGN
Originally Posted By: IndyIan
Originally Posted By: Shannow
I'd pick a different employer...this lot seems way too competitive.

Just go slicks, nitrous, and load up on sodium before the race

LOL, it does seem a bit competitive for a "fun" track day... I'm waiting to hear that the guy with the Scion is a top notch driver and brought a set of hoosier autocross tires and smoked them all... For a lap or two anyways...



That has crossed my mind numerous times lol. Geting beat by a Porsche is ok. A Scion would hurt.


Yeah, when I first started solo 2 again I got thrashed by an Hyundai Accent, it had so much bodyroll it was scary... Not that a H-stock Neon is expected to win FTD but it was motivation to get some sticky tires, add some camber, and eventually a rear sway bar. And I'm driving better too.

Does the track do timing for you guys? sectors even? It would be interesting to see all the laps at the end of the day.

 

[tom slick]

Have you been to Willow Springs before? It's a fun place, pretty laid back. I used to live just down the road from in the big city of Rosamond.
If you want an alternate route (more fun) to get there, take Tehachapi Willow Springs Rd. from Tehachapi. It cuts through the mountains and wind farms over to Tropico and Rosamond Blvd.

Maybe you guys should plan Buttonwillow next, it's a good track too.

 

[BuickGN]

Originally Posted By: tom slick
Have you been to Willow Springs before? It's a fun place, pretty laid back. I used to live just down the road from in the big city of Rosamond.
If you want an alternate route (more fun) to get there, take Tehachapi Willow Springs Rd. from Tehachapi. It cuts through the mountains and wind farms over to Tropico and Rosamond Blvd.

Maybe you guys should plan Buttonwillow next, it's a good track too.


Never been there but I can't wait to go.

I've actually passed Willow Springs Rd several times. Never thought that it would take me to Willow Springs lol. Sounds like a nice way to get "warmed up" for the track.

I used to work at the Enron/Zond Wind turbines, now GE, I believe.