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suganuma 10-28-04 10:56 PM

FD coilover spring rates
 
I've been trying to get some real world experience concerning the topic of spring rates on the FD and what different individuals have found to work better in different situations. I am specifically wondering about what everyone is using with their ground control coilover "kits". I guess when some people ordered their set a pre-determined set of springs came with them? I am currently running 500#F and 400#R with GAB super-Rs and the car tends to lean towards understeering at corner entry, which I thought was maybe just my novice skills causing me to approach the corner too hot but I drove a stock Subaru Impreza around the same slow/tight corners I play with around here without that issue.....we're talking ~30mph before turning in. I had the same issue the last time I went to a larger/higher speed track which caused me to not be able to carry a lot of speed into & around the corner. :\

Maybe it is something with the car or my driving. Either way I'm curious as to what rates you more experienced guys have found that you like.

TIA,

-Nic

Fritz Flynn 10-30-04 07:15 PM

Need a lot more info. What type sways frt and rr? What size wheels and tires front and rear. What's your alignment settings? etc...

Generally if you want turn in loosen the front and tighten the rear. The FD is really well balanced so my set up is really even front and rear. If I want some turn in I'll trail brake or using trailing throttle oversteer to point the car. These cars have incredibly good turn in.

The Gabs and the GCs are a great setup for the track and those spring rates are fine.


Originally Posted by suganuma
I've been trying to get some real world experience concerning the topic of spring rates on the FD and what different individuals have found to work better in different situations. I am specifically wondering about what everyone is using with their ground control coilover "kits". I guess when some people ordered their set a pre-determined set of springs came with them? I am currently running 500#F and 400#R with GAB super-Rs and the car tends to lean towards understeering at corner entry, which I thought was maybe just my novice skills causing me to approach the corner too hot but I drove a stock Subaru Impreza around the same slow/tight corners I play with around here without that issue.....we're talking ~30mph before turning in. I had the same issue the last time I went to a larger/higher speed track which caused me to not be able to carry a lot of speed into & around the corner. :\

Maybe it is something with the car or my driving. Either way I'm curious as to what rates you more experienced guys have found that you like.

TIA,

-Nic


suganuma 10-31-04 01:06 AM

Thanks for the reply Fritz, but I guess my post on the turn-in issue with the car probably belongs in another section. I haven't driven another FD, but my car compared to other cars I have driven does not have quick turn in (and I know that it should be better therefore my concern). I understand how I could drive the car around the issue or set it up so it would transfer the weight differently to counteract it, but I'd rather try to find out what the issue is if there is one.

The higher speed/longer track info could problem be thrown out as it was on the other tires with low tread in the front. I haven't been out on a higher speed course with the new tires.

I think all this probably belongs in another post though....
mods - feel free to delete anything above the next line.

How about I start over......

What spring rates are y'all using with which shocks and what settings do you find to work best for street/autoX/road course?

I have 500#-6" front/ 400# - 7" rear with GAB super Rs set at 5 front 3 rear.
unobtanium bushings
everything else is stock.
BFG KDWs 245/45/16 on stock wheels.

TIA,

Nic

DamonB 10-31-04 09:50 AM

Is the turn in problem in all corners or only corners of a particular speed?

What tires are on your car vs what you've driven? Different tires have different turn in characteristics, regardless of ulitmate grip. I've been on plenty of tires that were all good tires, but you still had to drive them slightly differently to get the most from them.

Shocks account for a lot of this too but the GAB R is a good shock and I know it to be even more agressive than my Konis.

Other than that I completely agree with Fritz. You really have to screw this car up to make it not turn it well as that's one of the things it does the best.

Mahjik 10-31-04 10:35 AM

suganuma,

I know a few people running Tokicos and GC coilovers. One of them ended up removing his R1 Strut bar and the rear sway bar to get the handling he was looking for on the track. He goes by RTS3GEN here on the forum if you want to PM him about his settings. I'm not sure what he has the Tokicos set to, but I would imagine 5's all around for the track.

The other guy I know running a similar setup ended up removing his rear sway bar as well but he didn't have a front strut bar to begin with.

I run Tokicos with the S-Tech springs which are 436F 324R. I put the Tokicos at 5F and 4R. That setup was real nice for my last event. Unfortunately, the motor didn't like it. :(

DamonB 10-31-04 11:54 AM

I have no idea how the valving of the front vs rear of a Tokico compares to the valving of the front vs rear of a Koni, but I have always found my car on Konis to work best (in any situation) with much stiffer front shocks than the rears. I always have boat loads more shock in the front of my car than the rear with the Konis.

Fritz Flynn 11-01-04 10:11 PM


Originally Posted by suganuma
Thanks for the reply Fritz, but I guess my post on the turn-in issue with the car probably belongs in another section. I haven't driven another FD, but my car compared to other cars I have driven does not have quick turn in (and I know that it should be better therefore my concern). I understand how I could drive the car around the issue or set it up so it would transfer the weight differently to counteract it, but I'd rather try to find out what the issue is if there is one.

The higher speed/longer track info could problem be thrown out as it was on the other tires with low tread in the front. I haven't been out on a higher speed course with the new tires.

I think all this probably belongs in another post though....
mods - feel free to delete anything above the next line.

How about I start over......

What spring rates are y'all using with which shocks and what settings do you find to work best for street/autoX/road course?

I have 500#-6" front/ 400# - 7" rear with GAB super Rs set at 5 front 3 rear.
unobtanium bushings
everything else is stock.
BFG KDWs 245/45/16 on stock wheels.

TIA,

Nic

Because these cars have such good turn in most people dial it out for high speed courses buy removing the rear sway or using a staggered wheel and tire combo etc...

I have the exact same setup as you on my car and it has awesome turn in. You can literally go into a drift at will. Like Damon I use full stiff on the front which would be an 8 with the Gabs and I use 6 in the rear. If you want more turn in use 6 front 8 rear. I would suspect that either your car is not corner weighted properly or aligned properly. It's amazing how much alignment can affect the handing of your car. For example if you have lots of camber in the rear and none in the front your car will push like mad. If you have the front coilovers pretty low and the rear pretty high it will also push like mad. Remember the more you raise one corner or the more tension you put on the spring the more weight that's tranferred to that portion of the car. It's counter intuitive but if you think about it like the spring is bench pressing and it pushing up the hardest then it's holding the majority of the load. Another thing to consider is Jims bushings are really difficult to maintain a susp setting because they are so stiff they literally bang themselves out of wack so you have to constantly monitor the settings. Also if you didn't install the complete kit front and rear then they would really stiffen whichever portion has his bushings.

My recommendation is to leave everything alone but have the car corner weighted and then aligned using the settings from Pettits web sight.

RedR1 11-02-04 04:07 AM

suganuma, I don't personally have experience with all of these coilovers, but I thought I would post their rates to help you out. I wish I had some first hand experience with the different models but I dont. All rates for these "out of the box" coilovers (most common ones among FD owners) are for the FD.

Zeal Function S6 and Function S6 - 504/448 lbs/in (street) 640/559 lbs/in (track)
JIC FLT-A2 - 671/504 lbs/in
HKS Hipermax II - 450/450 lbs/in
Tein Flex - 559/448 lbs/in
Tein RA - 895/895 lbs/in
Tein N1 with race springs - 1119/1119 lbs/in

RenoCYM 11-10-04 03:47 AM

What are the stock R1 spring rates??

suganuma 11-11-04 01:22 AM


Originally Posted by Fritz Flynn
My recommendation is to leave everything alone but have the car corner weighted and then aligned using the settings from Pettits web sight.

That's my current plan of action, but there isn't really anywhere in Del Rio (read edge of TX and Mexico) that I would trust with the car or would even know wtf I'm talking about if I took it to them. I plan on driving the car home to Dallas for Thanksgiving....Damon, maybe you could recommend a place? I've taken the car to get a quick/cheap alignment at a local Dallas firestone shop to see if that might fix the issue, but it did not. That was quite a while ago before a track session and the car was a handful b/c it simply wouldn't turn in toward the apex without having to slow down excessively. I am very much a novice so I'm sure y'all will side with that being the culprit, but I assure you that you would notice if you drove the car....even if only on the street.

Fritz, what are your spring rates & lengths out of curiousity. Sounds like from other posts that the car is fairly sorted out.

Thanks,

-Nic

DamonB 11-11-04 07:26 AM

I've been using the NTB at Beltline Road and I-35 for the past few years. The guy who runs their rack is very sharp and I always speak with him personally. I show him the numbers I want and he understands it's for a "race" car so I don't have to talk him into it. He is always dead on. I've also used a place in Frisco called Dallas Precision Imports. They're a small shop and also do a good job but they are far from me.

suganuma 11-11-04 11:46 PM

Thanks Damon, I'll look into those places.

I plan on trying out the Pettit long track settings.
Front:
Toe - 1/16" IN
Camber - -1.5
Caster - +6.0
Rear:
Toe - 0
Camber - -1.3

Unless y'all have a different suggestion....

racedriver 11-12-04 05:24 PM

I've road raced mine since 97. I run 650/ 450 , light mm front bar set at middle, stock rear bar, gab super r's set at max .=slight push in slow corners with toyo ra1's. neutral in most other stuations and drivable/ positionable with the throttle. With racing slicks i recommend 850/ 550.

We may enter speedvision in 05. Car is silver

wouter

fstfwd 06-16-05 01:51 PM


Originally Posted by RedR1
suganuma, I don't personally have experience with all of these coilovers, but I thought I would post their rates to help you out. I wish I had some first hand experience with the different models but I dont. All rates for these "out of the box" coilovers (most common ones among FD owners) are for the FD.

Zeal Function S6 and Function S6 - 504/448 lbs/in (street) 640/559 lbs/in (track)
JIC FLT-A2 - 671/504 lbs/in
HKS Hipermax II - 450/450 lbs/in
Tein Flex - 559/448 lbs/in
Tein RA - 895/895 lbs/in
Tein N1 with race springs - 1119/1119 lbs/in

Hey suganuma, sorry for jumpin in on your thread... but wanted to put a quick question in here.

I'm currently looking at either the HKS Hipermax IIs or the Tein Flex setup. I'm noticing that the TEINs have a little over 100lbs on the HKSs in the front springs... is that a considerable difference, or does the TEIN shock mellow that out a bit. Like others, I'm trying to improve performance a bit... while keeping my teeth :o). The roads here suck.

adax 06-16-05 02:09 PM


Originally Posted by suganuma
Thanks Damon, I'll look into those places.

I plan on trying out the Pettit long track settings.
Front:
Toe - 1/16" IN
Camber - -1.5
Caster - +6.0
Rear:
Toe - 0
Camber - -1.3

Unless y'all have a different suggestion....

I've tried the 0 rear toe and did not like it. It was almost undriveable in long sweeping corners. 1/8" in feels much better to me.

gnx7 06-17-05 02:31 PM

I have 550/450# springs with delrin bushings and GAB Super R's (8way adj).

front:
-2.1* camber
6.1* caster
zero toe

rear:
-1.3* camber
1/16 combined toe

Car handles awesome. Turn in is crisp and very predictable in other aspects.
285/30/18's all around.


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