Hi im looking to see what you guys recommend me for my rear springs i dont like how the rear of my car is now bouncy that i swapped to sportlines springs plus as soon as one passenger get in it rubs so bad i cant even more the car and i already rolled my rear quarters. heres a pic of my car im also runnin 27" tall tire

 

I went to call you and I guess I do not have your phone nunber- I messave you on facebook. Send me you phone number on there or I'll call Val and get it.

 

Can you guys post up any recommendations, I have a similar problem with the pro-kit.. Thinking about Global west or Gulstrand (I know they are old school) springs. Just wanted someone who has done some developement on these cars. I know you can take certain moog springs and trim to desired height. I was hoping for something more scientific. However if this is the easiest route, please advise. I want to keep it simple, I have Bilstien HD's already & know that they are, or seem slightly underdampened. Bilstien is local to me, so re-valving is not out of the question, just need the right spring /shock specs for a solid aggressive street/ mild autocross ride.

I don't want to give in to the ground control/ 900/200/koni quite yet because I already spent the money on what I have. what I would really like is to know how to get a 5" hyperco spring at the right size(length frt & rr) & rate and the right specs to revavle the Bilstiens. I know this may be a fantasy.

 

Your best bet would be to use Allstar weight jacks in the rear... I know, its not what your wanting. But it works.

http://pitstopusa.com/i-5066715-alls...uster-nut.html

You can then use a 5 x 10.5 inch spring or a 5x8 inch spring with whatever spring rate you want & have adjustability.

 

No that is great, Exactly the kind of info I was looking for.. what I meant is I would rather piece a custom kit with premium race quality parts for less$$ & awesome performance. Just Would you run the 10.5" or the 8" for street driven rear?

I've never seen anyone with solid revalve info, that would be great too. Or is a HD Bilstien enough to control a 150~200lb spring?

 

You can get more adjustment with the 8 inch spring; but a 10.5 inch spring will ride better.

Without looking at a dyno sheet I'm not sure if the HD Bilstiens are good or not out of the box. (but I've heard nothing but good things about them, so I assume they would work)

I would call Bilstien and tell them what your wanting to do with the car; and they should be able to valve them appropriately. Sorry I dont have better info than that...

Good luck with your build.

 

I could write a novel here and still not give a specific answer. It is only done through trail and error when dealing with spring and shock rate. I am currently on my 3rd spring rate change and 2nd of many to cone shock valving changes on our racecar going into race 4 of this season. Trust me when I tell you I spend hours of testing and data collection combined with my knowledge and still have to make guesses( albeit educated guesses) on the next purchase and or adjustments of shock and spring rate alterations. It's time and mobey- no substitute.

 

Thanks, That was my fear. I just don't have much time to develop my suspension through trial & error.(Would love to though) There seemed to be people used to regularly have custom shock/spring combos that were relatively simple. Also I know someone must have valving specs(lost art for thridgens). Just looking for a solid street set up that can be autocrossed . I know a good roadrace car would not be a good AX car & vice versa. Just want a balanced car with reasonably high road holding, neutral steering, & select chassis bracing. Maybe no simple way to get there. Car is 90% done just needs the final few suspension tweaks & tuning.

 

Noshow/Dean

For rear - should you use the pigtail style or is the standard spring OK. Is there a simlar set up for the front? I saw the front spring set up on TEDgrad's car and was wondering if there was an similar adjuster to the ground control units but a race part like is offered through pitstop. For the front what length? Sorry for all the questions, some of these have been answered in the past and some have not. Dean had the ultimate thread, I really wish it was still up - it was the best suspension info for a thirdgen I've seen.

 

A data point to consider: my 200lb rear springs combined with 900lb front springs felt really well balanced. Then I installed my jegs panhard bar adjuster and lowered the panhard bar. Now my steering feels heavier than it did before; and I believe I need to up my rear spring rates.. Thinking about going up to 250lbs to see how it feels. My point is it's taking me trial & error to get the feel of my car to where I like it; this is something you really cant avoid unless you just get lucky.

Just dialing in my shocks rebound made a big difference for me. You will have to make time to set your suspension to how you like with road testing.

I'm a little confused by these questions; are you asking about GC weight jacks VS allstars WJ set up? You will have to run 5" rear pigtail springs if your going with GC weight jacks. The Allstar weight jack set up I'm running in the *rear only* (pictured in post #4) is designed to take a 5" diameter regular coil spring; you do not need pig tail springs using allstars.

For the front I just went with 5.5" x 12" hypercoil springs from here:

http://pitstopusa.com/c-134738-sprin...x-12-tall.html

 

I could do spring rates on a car and let two different people here drive it- and get two different opinions on the feel of the car. It all boils down to driving style. How and why does this differ? I'll do my best to give two different examples/opimions of the same setup.

Lets take a car with 800 fronts and 225 rears. from compression rate is a 6 (of 1-12, 12 being firmest compression damper valving) which is actually quite firm for comp side, but not for rebound)- lets use a 6-6 (comp rebound) strut setting for this example.

Now based on car features (weights, ride height- ie roll centers in stagnant position, etc etc- the list goes on and on like tq arm lentgh, camber and caster settings, bushing deflection, chassis flex, brake bias, etc etc etc...you ge tthe drift) lets say this individual car and driver like this setup for a good balnced feel under braking and cornering...and it works for him.

...the next driver gets in the car and brakes a little later and harder. A little shorter braking zone but with alot more chassis attitude force change. What happens? the car does not turn initially until the *** end finally stands on end and highsides around from possible jacking effect of the rear. What changes? the dynamic laoding of the front spring rate "combined" with the "rate momentary build" of the front compression damper rate. This causes the front to go tight and plow under hard braking for a 2 second moment until the chassis nose dives to set . then upon release of brakes the car snapps back to softer front rate and the *** end climbs around into snap oversteer.

The smoother "sooner braking" driver set the chassis down more proportioned and the firmer front damper setting allowed for a sooner initial gradual turn-in of the car under balance, and then with a slow in and fast off style the driver gets onto the throttle sooner and leaves the corner with the *** end tight and planted arching off the corner with very good throttle imput because the front RC did not change into the snap oversteer.

Nopw to taylor the car to the second driver- you up the front spring rate to 900, and valve the shock to a 4-7. By lowering the comp rate, there is less change in dynamic loading under really hard braking. The car will be loose going in (loose enough to rotate under hard braking- but not under light braking) and then the lower front rebound will hold weight tranfer to the rears slightly more under hard initial throttle burst to momentarily keep the *** end tight and not snap out under abrupt throttle induction. The car will stat to gradually step out as the dynamic shock loading starts to occur at rear compression set but the front will follow suit as the higher front rebound difts the steering outward to 4 wheel drift off the corner under predictable stabiity. ... THis is this drivers style and loves the feel of the car- ye tthe first driver would be smoother on the pedal imputs and the car would not come off the corner without agressive oversteer imputs and pedal stabs.

Now take into account one person has iron heads (v8 car), and the next guy has aluminum heads and a heavy stereo amp setup out back- two totally different chassis dynamics of the somewhat identical car...or so you thought. This is why in a very short answer there is no perfect tried and true spring/shock combo. Now take all the other factors and your head will just go "aww screw it it's close enough" It's that final 10%-to-5-to-2% that will make or break a chassis overall setup. Anything else the typical car enthusienst will find "good enough". Im the type of freak that seeks that last 2% and will embarass a Corvette driver with a pickup truck becuase I know and understand how to make a vehicle handle to my driving style through testing and tuning and pedal work.

That leads to the next thing. I do not drive all vehicles the same. I drive them to how they need to be manipulated based on size and weight and modifications (or lack of) I do not take the same lines on a race course with every car- on the contrary I take very different lines with every car.

Just food for thought.

Dean

ps- if I could ever be so arrogant to float my own boat on here and express what I am better than anyone you would ever see do something? ...that is the uncanny ability to read a car on a track while not being in it. I have a gift to see things the average racer can not report to me- or generally will report the opposite. I have learned to trust my gut over theirs and make the changes I see, not what I hear from them. It takes many races before I can finally get a driver to learn what they need to tell me through testing and educating them on what they are to be feeling for when I make changes to a car. I have a gift in this area in life and it has been well witnessed at Toyota Speedway by many race teams that watch me in puzzlement and listen to my barking insructiuons to my crew as the car is coming off course after a test session. If I had a nickle for every time one of my peers asked me- how the heck did you see that? After the last race, I told Ronnie and the reast of the crew we have a shock issue. 4 days later I pulled down the RR and found a blown vlave on that shock with a 1/4" dead spot in travel stroke. I could see how the car was reacting coming off turn 2.

 

^^^Well put. There is no universal set up that handles well. With the F-body platforms massive weight differences from car to car; it becomes even harder to give someone advice on where to start.

Getting weight off the front of these cars is a must.

 

Excellent guys,

that is the info/advice I'm looking for. Gives me insight & some direction as to the fact I need to thoughroughly think this through and find a place where "I" will be happy with the cars handling.

Nowshow, so your running a standard 12" spring on the front without any type of weight jack? where do you end up on your ride hieght? Also Are you running a double adjustable shock? I'm a total novice here so I appreciate your bearing with me.

 

Right around 25" measured from the front fender lip to ground.

I'll give a more accurate measurement (within 1/10) after I get my engine re-installed. I'm swapping the 305 for a 383; so the front of my car is all jacked up off the ground without an engine lol. But now I'm thinking about swapping my vortec heads for a set of aluminum heads. The vortecs are nice; but iron heads are HEAVY. A 50lb+ weight savings up front from just a head swap is serious weight; especially that high up on the engine. Not to mention I'm dropping a TON of other stuff out of the engine bay as I type this. So my weight distribution will be much better with the new engine. (Also, my ride height will raise with the lighter set up; but I'm hoping to compensate by installed .75" extended BJ's from howe)

And no I'm just running regular off the shelf Koni sports. I'm hoping to go with some double adjustable S&S down the road; but I cant find any struts from a brand I like for our cars other than single adjustable struts. But Koni does have some nice double adjustable shocks that will bolt right up to our rears. But for the record, these single adjustable konis are really nice.

Keep in mind your ride height may vary depending on what options your car has.

 

NOSHOW,

Thinking about trying your set up with the jegster lowering bracket. Going 900/200 with a .75 spacer on the front to get a little more ride hieght, & use the all star adjusters on the rear. Thinking about the .75 BJ's too. Have you tried the stiffer rate rear springs yet? would you do 225, or do you think 250? Trying to get it right or close on the 1st shot. Going to see if Bilstein can get my shocks valved to match the rates with enough rebound. (They are litterally accross the street from where I work) so I'm gonna jump in and try to get the car fully sorted to be all it can be. Hope it's worth the effort I want to finish the car right and get it to handle.

 

Hey Kennerz;

I was going to use 250lb rear springs with .75 ext. BJ's. But I got a hold of some Belltech 2" Drop spindles, so it will take me some road testing to see if I need the increased rear spring rate now. My car is STILL on jack stands!
So I have not gotten a chance to drive the car with drop spindles to see how it feels.

If your car is lowered and has an Iron block v8 then I think 250lb springs would be the least I would run with a dropped panhard bar. This is based of my road testing with 200lb rear springs, no ext. BJ's & a dropped panhard bar (25.5" front fender height). 250lb rears still may not be enough. Only road testing would confirm if it feels right.