2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Need some help with spring rates.

Thread Tools
 
Search this Thread
 
Old Dec 15, 2008 | 06:32 PM
  #1  
sunburn's Avatar
Thread Starter
Mother****ing Wow
 
Joined: Jul 2008
Posts: 1,290
Likes: 0
From: NJ
Need some help with spring rates.

Sorry for the noob question -but I'm not really that knowledgeable in the word of suspension... figured I would turn to here for some help.

I ordered Stance AL+ pro coilovers for my FC and I have the option to pick any spring rate I want. They come with 9k front 7k rear, any suggestions on rates or should I just just go with the 9/7k? I plan on drifting and tracking the car, it will see the streets on the weekends and some cruising once in a while.

TIA

Last edited by sunburn; Dec 15, 2008 at 06:35 PM.
Reply
Old Dec 15, 2008 | 07:15 PM
  #2  
sunburn's Avatar
Thread Starter
Mother****ing Wow
 
Joined: Jul 2008
Posts: 1,290
Likes: 0
From: NJ

EDIT: Nevermind I got my answer. I'm going with the 9/7 and getting a 10/8 set as well.
Reply
Old Dec 15, 2008 | 09:52 PM
  #3  
w0ppe's Avatar
CC of L-Squared Shots
Tenured Member: 20 Years
 
Joined: Oct 2003
Posts: 644
Likes: 0
From: Columbus, Ohio
You sure about that? 9/7 rates are pretty stiff...
Reply
Old Dec 15, 2008 | 10:54 PM
  #4  
TitaniumTT's Avatar
Banned. I got OWNED!!!
 
Joined: Mar 2006
Posts: 1,970
Likes: 1
From: Connecticut
Yeah, I've got a set of 8/6 downstairs and 7/5 on the car now. I think you may have gone the wrong way

EDIT - Nevermind - drifter
Reply
Old Dec 16, 2008 | 12:17 AM
  #5  
Black91n/a's Avatar
Lives on the Forum
Tenured Member 10 Years
 
Joined: Sep 2003
Posts: 5,707
Likes: 6
From: BC, Canada
For drifting, fine, for the street use that you stated that you'll be using it for too, too stiff. I'm running 7/5 also and I wounldn't want to go any stiffer.
Reply
Old Dec 16, 2008 | 06:12 AM
  #6  
sunburn's Avatar
Thread Starter
Mother****ing Wow
 
Joined: Jul 2008
Posts: 1,290
Likes: 0
From: NJ
Originally Posted by w0ppe
You sure about that? 9/7 rates are pretty stiff...
If I was going to DD the car I would go with something softer... but this is going to be a weekend warrior/track car.
Reply
Old Dec 16, 2008 | 03:41 PM
  #7  
kleetuz's Avatar
Senior Member
Tenured Member 15 Years
iTrader: (2)
 
Joined: Oct 2001
Posts: 377
Likes: 0
From: West Los Angeles
9/7 is way to stiff for the street, but could be bearable as long as you set the dampers to be pretty soft. And I would venture about as stiff as you would want to go. 500lb/in and 390lb/in - That's stiff. But if you are on a smooth track this would work well as the car won't be disturbed by random bumps and cracks in the track surface. The guys at stance know what they are doing, but they are testing this on very nice tracks (compared to streets or parking lot autocrosses) from the videos I've seen.

But drifting doesn't necessarily mean you have to get rid of your grip to do it, you just need to find a balance where the springs make the car neutral and the response is fast enough that you can control the car properly. If you go with rates that high you will really need a larger anti roll bar front and rear to control the roll of the car properly, those springs will easily over power the stock anti roll bars.

Though this was not intended for a drift based setup... I ordered 7/5 and have now gone to 6/5 which has really balanced the car out towards neutral and made the front end track much better. Driving around on the street is very reasonable with this setup and at the limit the car is quite neutral. Also I'm just using the stock anti roll bars, which really need to be upgraded.

Really with suspension it's all about the balance, especially for drifting where you are beyond the limit all the time.
Reply
Old Dec 16, 2008 | 05:31 PM
  #8  
sunburn's Avatar
Thread Starter
Mother****ing Wow
 
Joined: Jul 2008
Posts: 1,290
Likes: 0
From: NJ
Originally Posted by kleetuz
9/7 is way to stiff for the street, but could be bearable as long as you set the dampers to be pretty soft. And I would venture about as stiff as you would want to go. 500lb/in and 390lb/in - That's stiff. But if you are on a smooth track this would work well as the car won't be disturbed by random bumps and cracks in the track surface. The guys at stance know what they are doing, but they are testing this on very nice tracks (compared to streets or parking lot autocrosses) from the videos I've seen.

But drifting doesn't necessarily mean you have to get rid of your grip to do it, you just need to find a balance where the springs make the car neutral and the response is fast enough that you can control the car properly. If you go with rates that high you will really need a larger anti roll bar front and rear to control the roll of the car properly, those springs will easily over power the stock anti roll bars.

Though this was not intended for a drift based setup... I ordered 7/5 and have now gone to 6/5 which has really balanced the car out towards neutral and made the front end track much better. Driving around on the street is very reasonable with this setup and at the limit the car is quite neutral. Also I'm just using the stock anti roll bars, which really need to be upgraded.

Really with suspension it's all about the balance, especially for drifting where you are beyond the limit all the time.
Thanks for your input... I did talk to someone at Stance when sorting out the rates, he does in fact, drive an FC... I will certainly be upgrading the sways and giving basically then entire suspension/drivetrain a good workover (diff, clutch, bushings, ect) Later down the road I can always simply order another set of springs at whatever rate I want... I know to some people they may seem a bit stiff -but that is what I'm used to and suits my driving style well.
Reply
Old Dec 16, 2008 | 07:22 PM
  #9  
TitaniumTT's Avatar
Banned. I got OWNED!!!
 
Joined: Mar 2006
Posts: 1,970
Likes: 1
From: Connecticut
Bushings will make the biggest difference in the way the car handles and cost about 10-15% of what a set of coilovers will run
Reply
Old Dec 16, 2008 | 10:01 PM
  #10  
w0ppe's Avatar
CC of L-Squared Shots
Tenured Member: 20 Years
 
Joined: Oct 2003
Posts: 644
Likes: 0
From: Columbus, Ohio
Thicker Anti-roll bars as well to help with the "Squirrly" effect helps.
Suspension tuning is about movement of the car. Anything that deals with the movement of anything about the car is part of it. If you ever feel like your adjustments aren't doing anything to help, try adjusting something else!
Reply
Old Dec 17, 2008 | 04:41 AM
  #11  
sunburn's Avatar
Thread Starter
Mother****ing Wow
 
Joined: Jul 2008
Posts: 1,290
Likes: 0
From: NJ
Originally Posted by w0ppe
Thicker Anti-roll bars as well to help with the "Squirrly" effect helps.
Suspension tuning is about movement of the car. Anything that deals with the movement of anything about the car is part of it. If you ever feel like your adjustments aren't doing anything to help, try adjusting something else!
will be doing a set-up very close to this:

http://www.ziptied.com/forums/index.php?topic=7676.0
Reply
Old Dec 17, 2008 | 11:44 AM
  #12  
TitaniumTT's Avatar
Banned. I got OWNED!!!
 
Joined: Mar 2006
Posts: 1,970
Likes: 1
From: Connecticut
You have much to learn about the difference between race cars and street cars
Reply
Old Dec 17, 2008 | 02:19 PM
  #13  
eage8's Avatar
1308ccs of awesome
Tenured Member: 20 Years
iTrader: (9)
 
Joined: Sep 2003
Posts: 6,189
Likes: 18
From: Woodbine, MD
I have 7/6 on my car which is not a daily driver..., 9/7 is going to be rough... good luck.
Reply
Old Dec 17, 2008 | 02:56 PM
  #14  
Gene's Avatar
10 lb. boost, 5lb. bag
Tenured Member 10 Years
iTrader: (1)
 
Joined: Mar 2001
Posts: 1,075
Likes: 2
From: New York, NY
I have Tein Super Drifts on my FC which are 8/6. I wouldn't call it comfortable but with the dampers dialed to a soft setting they are bearable. This isn't a DD though, I drive the car like twice a month. I've got the RB front bar, no rear bar, and the handling is excellent. I use it for HPDE, not drifting. The bump and rebound curves on the Super Drift are substantially different than Tein's Flex setup, but a little experimenting with the damper settings made the car very neutral and easy to drive. For track tires I run 225F and 245R BFG-R1s.
Reply
Old Dec 17, 2008 | 03:02 PM
  #15  
Rexpelagi's Avatar
53.6%/46.4% - Crap!
Tenured Member 10 Years
 
Joined: Apr 2006
Posts: 337
Likes: 1
From: Canton, OH
I will be running 525 lb/in in the front and 375 lb/in in the rear for my spring rates with Koni Sports, but I most likely have slightly more weight in the front than you. I have no idea how it will ride and unfortunately I won't know until it gets warmer so I probably won't be able to help in time, but I will let you know how it goes.
Reply
Old Dec 17, 2008 | 03:12 PM
  #16  
sunburn's Avatar
Thread Starter
Mother****ing Wow
 
Joined: Jul 2008
Posts: 1,290
Likes: 0
From: NJ
Originally Posted by Rexpelagi
I will be running 525 lb/in in the front and 375 lb/in in the rear for my spring rates with Koni Sports, but I most likely have slightly more weight in the front than you. I have no idea how it will ride and unfortunately I won't know until it gets warmer so I probably won't be able to help in time, but I will let you know how it goes.

we will be about the same.. a 9/7 metric split would be 504 lb/in front and 392 lb/in rear.
I'll post reviews when I get them... my car is going to be "front heavy" soon
Reply
Old Dec 17, 2008 | 03:23 PM
  #17  
Rexpelagi's Avatar
53.6%/46.4% - Crap!
Tenured Member 10 Years
 
Joined: Apr 2006
Posts: 337
Likes: 1
From: Canton, OH
Originally Posted by sunburn
we will be about the same.. a 9/7 metric split would be 504 lb/in front and 392 lb/in rear.
I'll post reviews when I get them... my car is going to be "front heavy" soon
Yep, I noticed my rates were real close to yours so that's why I responded. Maybe we can get a CF fender/hood group buy going to take care of these damn front heavy cars...
Reply
Old Dec 17, 2008 | 09:57 PM
  #18  
w0ppe's Avatar
CC of L-Squared Shots
Tenured Member: 20 Years
 
Joined: Oct 2003
Posts: 644
Likes: 0
From: Columbus, Ohio
Originally Posted by sunburn
will be doing a set-up very close to this:

http://www.ziptied.com/forums/index.php?topic=7676.0
I don't trust anyone that is going to say throw the rear-sway bar away...
If it's drifting I guess it's fine since the rear-end will bend side-ways a lot; but, you'll notice a huge difference when you try and accelerate out of a corner...
Reply
Old Dec 17, 2008 | 10:12 PM
  #19  
TitaniumTT's Avatar
Banned. I got OWNED!!!
 
Joined: Mar 2006
Posts: 1,970
Likes: 1
From: Connecticut
I know of a few pro road race teams that run no sway bar in the rear on FC's
Reply
Old Dec 17, 2008 | 10:15 PM
  #20  
Black91n/a's Avatar
Lives on the Forum
Tenured Member 10 Years
 
Joined: Sep 2003
Posts: 5,707
Likes: 6
From: BC, Canada
Many, MANY road racers ditch the rear sway bar. It HELPS traction out of the corner to not have it there, since you're not unloading the inside wheel with the sway bar. If your spring rates are set up for it not being there, the car will handle just fine.
Reply
Old Dec 18, 2008 | 05:50 AM
  #21  
sunburn's Avatar
Thread Starter
Mother****ing Wow
 
Joined: Jul 2008
Posts: 1,290
Likes: 0
From: NJ
Originally Posted by Black91n/a
Many, MANY road racers ditch the rear sway bar. It HELPS traction out of the corner to not have it there, since you're not unloading the inside wheel with the sway bar. If your spring rates are set up for it not being there, the car will handle just fine.
Yeah I know people that have tried all sorts of rear sway bar set-ups and at the end of the day running without one always netted better results.
Reply
Old Dec 18, 2008 | 08:47 AM
  #22  
w0ppe's Avatar
CC of L-Squared Shots
Tenured Member: 20 Years
 
Joined: Oct 2003
Posts: 644
Likes: 0
From: Columbus, Ohio
Maybe I just suck then. I'm just basing that on my own experience of with and without. I like it with.
Reply
Old Dec 18, 2008 | 08:54 AM
  #23  
TitaniumTT's Avatar
Banned. I got OWNED!!!
 
Joined: Mar 2006
Posts: 1,970
Likes: 1
From: Connecticut
The springs you're using are probably too soft to control the car properly without a rear sway bar. I certainly wouldn't suggest you bump your rates to 350-400lb rear springs just to not use a sway bar unless it's a track only car though. The **** it, keep experimenting. But like you said above, 9/7 is probably too stiff and from the guys I've spoken too, that's about where they start with rear springs, right in the 350 and above range.

Again, huge difference between a track car and a street car. Street car drivers are going to want springs/shocks that are alot more forgiving for some of the shittier roads. A track car is going to be under more cornering loads over a smoother surface and can benefit from a stiffer spring/shock to deal with the cornering loads while allowing the IRS to be as independant as possible for traction reasons.
Reply
Old Dec 18, 2008 | 08:16 PM
  #24  
Black91n/a's Avatar
Lives on the Forum
Tenured Member 10 Years
 
Joined: Sep 2003
Posts: 5,707
Likes: 6
From: BC, Canada
Also keep in mind that a race car with a stripped out interior will have a lot less weight over the rear than a street car with a full interior, which will affect the handling balance. So a street car might need a rear sway with the same rates as a race car that doesn't.

I'm running 7/5 springs an RB front bar and the stock rear bar with a full interior, roll bar, no AC, no PS and it's ever so slightly understeery.
Reply
Old Dec 18, 2008 | 09:51 PM
  #25  
BLUE TII's Avatar
Rotary Motoring
Tenured Member: 25 Years
Liked
Loved
Community Favorite
iTrader: (9)
 
Joined: Mar 2001
Posts: 8,479
Likes: 932
From: CA
Yep, another vote for no rear swaybar.

I just tried it on the CSP car.

2400lbs
comp bushings, toe elim
16x7.5/16x8 w/ 245/45 RA1
JIC FLT-A2 7/5 rates

The car was very oversteer happy. I think it is the valving of the rear shocks- no matter what you do it oversteered and you had to keep up constant adjustments to keep the rear in line.

Without the rear bar there IS some understeer if I turn in too fast (instead of oversteer), but it seems to be very neutral at the limit and is still driftarific if your inputs are too hard. Feels more like it did with shocks/lowering springs and the rear bar.

The rear seems less harsh in damping at the same setting and the rear tires seem more stable over bumps.

I think the advantages of taking off the swaybar has to do a lot with keeping the rear trailing arms independent in movement (ESPECIALLY with short stroke suspension) and eliminating the binding.

I will try it on the SM2 car as well, though I expect less of a difference due to the spherical bearing swaybar end links on that car that eliminate much binding.
Reply



All times are GMT -5. The time now is 06:03 AM.