SPRINGS-which work best?

[GS70350]

Need some traffic in the forum, which by the way is an excellent and needed addition to the board, thanks.
Anyway, i see a spring chart on another thread. My question is, which springs work best for a road course/autocross type situation, without giving up too much on the straightline traction.

I dont want the spring rates to be too stiff like 700 lbs springs up front, i think there is a limit where stiffer is not better. Of course our cars are heavy and may need stiffer springs. Whats the best to use up front?

On the back, the spring rates are quite low from the factory. what should be used in the rear? I would really like to be able to trim the springs, so some camaro type with single pigtails would be nice.

Thanks

 

[Racer X]

I run 600# in the front and 135# in the rear. This seems to work pretty well for me. You are right, there is a limit to the spring rates on both the high and the low side. If you get too soft the car will roll over too much and put too much weight on the outside tires causing them to lose grip. On the other hand, if you get the springs too stiff, the car will not roll over enough and it will feel like it's skating.

Of course, just like the engine recipes, there is a suspension recipe as well. Stiffer springs need softer sway bars and softer springs need stiffer sway bars.

 

[GS70350]

Saw on laureneng.com that they sell something they call a rear sway bar update kit. basically, it looks like they put 2 mid links on the sway bar connecting it to the axle tubes. For 127 bucks it seems way to expensive, but would this actually help much?

Right now my car has stock suspension and bilstein shocks, it does what you say and rolls over on the outer tires around turns. Also it has positive camber. Is there a way to adjust for some negative camber in the alignment? From what i hear its not very easy. thanks

 

[Chad Oliver]

I've heard of 2 schools of thought for autocross regarding springs: heavy spring, small swaybar or light spring, big swaybar.

 

[Racer X]

Originally posted by GS70350
Saw on laureneng.com that they sell something they call a rear sway bar update kit. basically, it looks like they put 2 mid links on the sway bar connecting it to the axle tubes. For 127 bucks it seems way to expensive, but would this actually help much?

The rear sway bar is kinda like a spring that runs from one side of the car to the other to help transfer weight. What they have done there is effectively cut the bar into thirds thus making the bar stiffer. They even say on the site that it makes a 7/8" bar *feel* like an 1-1/4 bar. I would prefer to just have the bigger bar, but that's just me

Originally posted by GS70350
Right now my car has stock suspension and bilstein shocks, it does what you say and rolls over on the outer tires around turns. Also it has positive camber. Is there a way to adjust for some negative camber in the alignment? From what i hear its not very easy. thanks

I just take my car to the local alignment/tire store and have them set the car to my specs. I am lucky enough that the shop has the latest Hunter Alignment Rack I run 255/45/16 in the front and I can't get much more than -1.5*. A little trick to see how much rollover you are getting is to take some white shoe polish and mark from just up on the tread and come down the sidewall a couple of inches and then go out and hit a twisty road and then see how much shoe polish is gone.

 

[GS70350]

Yea, when i was at the autocross/road course thing, the chalk wasnt necessary, i just saw my sidewall disapear instead. around 1.5 inches of roll over if thats what that is. now my sidwall tread is next to gone, what do you suggest doing.

 

[GS70350]

only on the front tires of course, the backs have no wear whatsoever, fronts were at 45 psi, backs at 38, thats where Eric set them that worked best on the course, he was driving.

 

[Racer X]

Are you still using 15" tires? It sounds like you are to be running that kinda tires pressure

You need to dial in as much negative camber as your car will allow. However, I would not run a bunch of camber for everyday driving. You will wear out the tire unevenly and you will no longer have any effective camber. I only set the aggresive camber setting for the track.

What's happenig to your car is that when you turn in, the outside tires are changing their slip angle and going into positive camber and you are only using the outer edge of the tire(not a lot of grip). So by setting the car to, oh lets say -1.5* your are riding on the inner edge of tire down the straights. Then when you get into the corner and you turn in the slip angle of the tire will (hopefully) go to 0* camber, meaning that the whole tire is now in contact with the pavement(contact patch), and that's maximum grip (and that's much faster ).

I run 255/45/16 on all four corners. I ran with the 15" tires a couple of times and I thought I was going to drive the tires right off the rims

 

[GS70350]

still using stock 87 GN rims with yokohama AVS intermediates. 15 inchers yes.

I cant get any 16 inch rims for cheap, if i could i would already have them. My budget for rims and tires is going to be 276 dollars, if i can get some nice used tires and some GTA style rims then ill do that but its not easy.

Anyone know where i can get a set this cheap? gotta stay in the budget.

 

[turbo buicks]

my buddy (red regal t) runs 16 inch IROC Camaro rims on his T type. im sure you could find a set of cheap used ones. also check summit. they got some gay ass lookin rims but they are cheap as hell.