Understanding spring rates on other cars - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Dee240sx · 06-06-2005, 08:56 AM

A friend of mine has an 02-03 RSX. He has tein c/o's with EDFC and I believe his spring rates are something like 8f / 10 or 12R. Now i've driven in this car a few times and it actually rides pretty damn comfortable ( even on highways like the Grand Central Parkway - NYC). Certainly something I could deal with. A little bouncy at times but again, totally acceptable.

Now inregards to the 240. The common spring rates for a lot of c/o's are 8/6 to which many consider and suggest might be too stiff for daily driving on NYC/NJ roads. 8/12 or even 8/10 would be considered VERY stiff on a 240 and certain not suggested for daily driving (I don't think i've even seen spring rates that are higher in the rear then in the front for 240's).

My question is why is a car like a RSX with those springs rates not nearly as stiff as a 240 would be with the same rates?

I was hoping to get a good or close enough example of how my s14 would feel with 8/6 rates by driving in his car, but with the higher rates on the RSX, that threw my little experiment for a loop.

Var · 06-06-2005, 10:31 AM

Cars with double wishbone suspension have a different effective springrate. You'd need a stiffer spring to get the same feel on a double wishbone. I dunno much about honda's but the RSX may have a rear stiff setup to counter understeer. The comfort level in a car is ALL determined by the rear spring spring rate and shock valving. I have Tein HA's. On a soft setting, they are really comfortable, and on stiff, still daily driveable. 2 different coilovers with the same spring rates can also be dramatically different depending on shock valving. Basically..spring rates dont mean much. It's all in the shocks. WHat kinda coils are you interested in buying?

DocTaDrifT · 06-06-2005, 10:35 AM

i have kei office coils on my car and its so stiff i was gettin sick after driving when i first got them hahaha

orion::S14 · 06-06-2005, 10:41 AM

A lot of it is in the shocks (ride comfort and smoothness)...

And as it has been said here...the "wheel rate" of a MacPherson setup is the spring rate (8K spring rate = 8k wheel rate). On a Honda (double wishbone), a 10k spring rate will most likelybe a 5k wheel rate.

See the difference?

It all depends on suspension geometry.

- Brian

95Blue240sx · 06-06-2005, 10:48 AM

Finally a good question that im happy to read.

Anyways it makes a lot of sense. I have HA on my car with 6/5 rates. It set really soft and it still feels everybump on the road. I dont get how some people ride with 8/10 + setups. CRAZY.

Good question though.

pruto · 06-06-2005, 10:50 AM

geez people, we say this EVERYTIME the question springrate vs. comfort comes up:
ride comfort for a coilover is dependant on spring rate AND valving.

8/6 on a tein feels different than 8/6 on Kei's office at the track, it also feels different on the street as well.

also stiffness is dependant on other suspension components as well, how stiff or mushy the arm joints.

my 9/7 on my apex'i N1 pros felt amazing on the street when i first got them. The ride got worse when i replaced all my rear arms and worse still recently when the shocks are starting to go out.

as for other cars, spring rate choice is sorta based on suspension geometry and the weight and weight distributions of cars. Most double wishbone FF hondas have standard coilover rate of like 8/5 or something since most of the weight is up front. 350Zs on the other hand have a higher standard coilover spring rate than 240s at least partially because of the extra weight.

anyway, to keep pounding the point in. By riding in a car with coilovers, you can not acurately judge the comfort level you should expect in your car with a different set of coilovers, even if it is the same spring rate.

WongFeiHung · 06-06-2005, 10:50 AM

The solid RSX chassis probably makes it "feel" more comfortable also...

Dee240sx · 06-06-2005, 11:13 AM

Quote:

Originally Posted by westboroughpimp

Cars with double wishbone suspension have a different effective springrate. You'd need a stiffer spring to get the same feel on a double wishbone. I dunno much about honda's but the RSX may have a rear stiff setup to counter understeer. The comfort level in a car is ALL determined by the rear spring spring rate and shock valving. I have Tein HA's. On a soft setting, they are really comfortable, and on stiff, still daily driveable. 2 different coilovers with the same spring rates can also be dramatically different depending on shock valving. Basically..spring rates dont mean much. It's all in the shocks. WHat kinda coils are you interested in buying?

Alright so using the shock valving as as better way of determining the comfort of daily drivability, what types of shock valving (inverted, monotube, etc - is that correct?) are there? Is one type of shock valving more suitable for comfort instead then another? Is there a way to rate the valving like you see with the spring rates?

Right now i'm considering a few different brands of c/o's (based on few things like price, speaking to people who own them and that I trust their opinions, brand, warranty, rebuildable, etc)

Megan Racing
Silk Road (RM8)
Tein SS
Tein HA
KTS

Megan and KTS being the most afordable and the Tein and Silk Roads being the higher priced brand but come with a great names and a proven track record for themselves. There's more to it that I've been taking into consideration so don't limit this to just price.

Like someone else stated in this thread, I fully understand that upgrading other suspension parts will also affect the comfort of driving. In my last s13 I replaced the bushings in my front end suspension (T/C rods, stb, LCA, etc) with Poly Urethane bushings from PDM. Given my OE bushings were shot to shit the Poly U bushings basically just cleaned up and improved (big time) the sloppy front end. The rich harshness I was already used to.

Dee240sx · 06-06-2005, 11:15 AM

Quote:

Originally Posted by pruto

anyway, to keep pounding the point in. By riding in a car with coilovers, you can not acurately judge the comfort level you should expect in your car with a different set of coilovers, even if it is the same spring rate.

My bad for mis-leading, I certainly didn't intend on walking away from riding in my boy's car based on his c/o's knowing what spring rate I wanted. I just trying to use his car as sort of an example.

I need to make it out to some local NJ/NYC meets and take rides in people's cars who are willing to do so.

Var · 06-06-2005, 11:20 AM

Quote:

Originally Posted by Dee240sx

Alright so using the shock valving as as better way of determining the comfort of daily drivability, what types of shock valving (inverted, monotube, etc - is that correct?) are there? Is one type of shock valving more suitable for comfort instead then another? Is there a way to rate the valving like you see with the spring rates?

Shock valving isnt the same as monotube, or twin tube, or inverted. Valving is how the shock is built to absorb the road. Some shocks are built for extremely fast piston speed with long travel and soft valving to absorb really bumpy terrain. Some are valved really stiff and matched with really stiff springs and can work with only one inch of shock travel. This is the stuff for the racetrack. Valving is how the shock is "programmed"

Dee240sx · 06-06-2005, 11:33 AM

Quote:

Originally Posted by westboroughpimp

Shock valving isnt the same as monotube, or twin tube, or inverted. Valving is how the shock is built to absorb the road. Some shocks are built for extremely fast piston speed with long travel and soft valving to absorb really bumpy terrain. Some are valved really stiff and matched with really stiff springs and can work with only one inch of shock travel. This is the stuff for the racetrack. Valving is how the shock is "programmed"

Thank you for clearing that up, but how would I go about finding out how the shocks are setup to perform? Manufacturer website?

Var · 06-06-2005, 11:51 AM

Quote:

Originally Posted by Dee240sx

Thank you for clearing that up, but how would I go about finding out how the shocks are setup to perform? Manufacturer website?

Most manufacturers will give a description of their products, but it's mostly relative to other stuff that they sell.

Out of the coils you listed, i have ridden in cars with HA(mine) and KTS(bobbyboy) but i didnt really get a chance to feel the KTS on a stiff setting. On half way it was decent..not too stiff not too soft. I think the HA would make a great coil for daily driving if you're concerned about streetability..this is all of couse just my opinion to what is comfortable..and the roads here arent bad so take that into consideration.

The coils you listed.

Tein HA and Tein SS would be my thoughts on street coils.

KTS and Silkroad would be more on the performance side, but this is without riding in a car equipped with them. These are based on their reputations. Unfortunately the only shock dyno out of these that i know of are on the KTS, and if i'm reading them correctly, then they are pretty stiff.

Dee240sx · 06-06-2005, 01:42 PM

Quote:

Originally Posted by westboroughpimp

Most manufacturers will give a description of their products, but it's mostly relative to other stuff that they sell.

Out of the coils you listed, i have ridden in cars with HA(mine) and KTS(bobbyboy) but i didnt really get a chance to feel the KTS on a stiff setting. On half way it was decent..not too stiff not too soft. I think the HA would make a great coil for daily driving if you're concerned about streetability..this is all of couse just my opinion to what is comfortable..and the roads here arent bad so take that into consideration.

The coils you listed.

Tein HA and Tein SS would be my thoughts on street coils.

KTS and Silkroad would be more on the performance side, but this is without riding in a car equipped with them. These are based on their reputations. Unfortunately the only shock dyno out of these that i know of are on the KTS, and if i'm reading them correctly, then they are pretty stiff.

Since you posted this...

Do you have any preference or opinion on the c/o that Megan Racing just put out?

killjoy · 06-06-2005, 01:52 PM

This link shows a load of useful info on suspension and also shows spring rates for almost every manufacturer.

http://texas240sx.com/forums/showthr...?p=677#post677

Var · 06-06-2005, 02:29 PM

Quote:

Originally Posted by Dee240sx

Since you posted this...

Do you have any preference or opinion on the c/o that Megan Racing just put out?

umm..i dont wanna say anything negative about megan except that i dont know anyone who's opinion i trust about suspension that has said anything good about them. There are people that are happy with them, as there are people that are happy with D2's..and i wouldnt use either of those. But that's me. different people have different needs. Honestly..i would probably go for the KTS *for myself* as a daily driver coilover, and something stiffer for my track car. But then again..the HA's aren't that bad either...and i'm getting by with them for drifting even though they are a lot softer than what the other guys at the track use.

NismoSilvia270R · 06-06-2005, 06:52 PM

Quote:

Originally Posted by westboroughpimp

Shock valving isnt the same as monotube, or twin tube, or inverted. Valving is how the shock is built to absorb the road. Some shocks are built for extremely fast piston speed with long travel and soft valving to absorb really bumpy terrain. Some are valved really stiff and matched with really stiff springs and can work with only one inch of shock travel. This is the stuff for the racetrack. Valving is how the shock is "programmed"

idk if you read stuff on corollas, but ive been looking at how those guys make their custom coilover setups and they always talk about getting the right shock for spring.

im wondering how 'too stiff' of springs can blow a shock prematurely. what kind of 'programming' can be used to match shocks and springs? for ex. a line graph that shows what kind of dampening works better with certain springs rates.

also, do shocks blow if their entire stroke isnt being utilized?

Dee240sx · 06-07-2005, 08:30 AM

Quote:

Originally Posted by westboroughpimp

umm..i dont wanna say anything negative about megan except that i dont know anyone who's opinion i trust about suspension that has said anything good about them. There are people that are happy with them, as there are people that are happy with D2's..and i wouldnt use either of those. But that's me. different people have different needs. Honestly..i would probably go for the KTS *for myself* as a daily driver coilover, and something stiffer for my track car. But then again..the HA's aren't that bad either...and i'm getting by with them for drifting even though they are a lot softer than what the other guys at the track use.

In defenese of MR. Jeff240sx made that long post about them over here and @ FA. The general consensus seems to be positive about MR c/o's. I've also spoken to a few people who have them and they recommend them.

Bottom line : I need to get my ass in some c/o equipped 240s.

Var · 06-07-2005, 03:27 PM

hey..stupid me for never checking. The tein HA come with 6/5 springs, not 8/6. No wonder my shit is so damn comfortable. Anyways. I think you should go with the HA.

24Dee · 06-07-2005, 09:13 PM

Quote:

Originally Posted by westboroughpimp

hey..stupid me for never checking. The tein HA come with 6/5 springs, not 8/6. No wonder my shit is so damn comfortable. Anyways. I think you should go with the HA.

How come everywhere i've looked, no one seems to carry Tein HA's

I vaguely remember reading somewhere that Tein wasn't make HA's anymore???

HA's come with camber plates or are they additional?

Var · 06-08-2005, 09:27 AM

any coil is available with. If they are discontinued that's too bad, cause they are an awesome street setup. Also soft enough to absorb fucked up touge's on softer shock settings and stiff enough to drift with.

Dee240sx · 06-09-2005, 06:32 AM

Quote:

Originally Posted by westboroughpimp

any coil is available with. If they are discontinued that's too bad, cause they are an awesome street setup. Also soft enough to absorb fucked up touge's on softer shock settings and stiff enough to drift with.

What I meant is were camber plates included in the price of the HA?

food for thought : I've recently spoken with someone about the M/R c/o's and he said between the 7/5 Cusco's and 8/6 Apex c/o's he's owned, the M/R were definitely the most comfortable. He also said that they are a very quality built product and great bang for the buck. He lives in my area and drives on the same roads I do.

orion::S14 · 06-09-2005, 06:38 AM

Camber plates are(were?) included with HE's....but not HA's.

- Brian

TheTicTac · 06-09-2005, 07:18 AM

hmm? I've always thought that the reason that FF have higher rates in the rear was to keep the weight transfer at the front longer. It never occured to me that wheel rates or suspension geometery made a difference, learn something new everyday.

MakotoS13 · 06-09-2005, 07:55 AM

GRAN TURISMO. ever try to tune a fwd car vs a rwd car in that game? the reawr is stiff as hell cause all it does is basically keep the car steady. they NEED stiff rear to help induce oversteer. with rwd cars you have tires that actually do something in the back so the situation is changed dramatically because you now need the body to sit back on its "haunches" under acceleration but not so much that it gets sloppy in a turn.

idunno, i just figure tuning a FWD car is a lot easier due to these observations.

Dee240sx · 06-09-2005, 08:05 AM

Quote:

Originally Posted by orion::S14

Camber plates are(were?) included with HE's....but not HA's.

- Brian

Any info on whether or not HA's are discontinued?

orion::S14 · 06-09-2005, 10:47 AM

Never heard that they were discontinued...

See here: http://www.tein.com/nissan.html - They're still listed for S14.

HE's were supposed to be replaced with some other "drift spec" coilover...and they are no longer listed there.

- Brian

Ian · 06-09-2005, 11:30 AM

the HA was replaced by the HE and then the HE was replaced by the "super drift" i believe

i have MR coilovers, i had a small issue w/ one of them breaking on me (shock blew prematurely) so i mailed it back and they replaced it within a week. other then that, great quality for the price. If you CAN afford better ones, do it...I suggest getting MR if there is little possibility of you coming up w/ the extra 400-500 or so to get better ones.

if you have extra money, i hear good things about:
silk road
KTS
Tanabe DD (best ones before you go into super expensive pro stuff)

axiomatik · 06-09-2005, 11:38 AM

There are several reasons why FWD cars have stiffer springs in the rear. First, a stiffer rear spring will reduce weight transfer on acceleration, providing more traction to the front wheels. Second, FWD cars are very nose-heavy, creating more understeer. A stiffer rear suspension reduces understeer and makes the car more neutral.

Also, to address an earlier question, there isn't really an 'ideal' damping level for a given spring rate, since so many people drive so differently and have different ideas on how their car should handle. However, there is an optiomal range. If a damper is too weak (for example, when your shocks are blown), the spring will continues to oscillate for several cycles after hitting a bump, causing unpredictable handling. If a damper is too strong, it will take the spring too long to return to its equilibrium position after hitting a bump, again resulting in unpredictable behavior.

06-06-2005, 08:56 AM	#1
Dee240sx Leaky Injector Join Date: Feb 2003 Location: North Jersey Posts: 55 Trader Rating: (0) Feedback Score: 0 reviews	Understanding spring rates on other cars A friend of mine has an 02-03 RSX. He has tein c/o's with EDFC and I believe his spring rates are something like 8f / 10 or 12R. Now i've driven in this car a few times and it actually rides pretty damn comfortable ( even on highways like the Grand Central Parkway - NYC). Certainly something I could deal with. A little bouncy at times but again, totally acceptable. Now inregards to the 240. The common spring rates for a lot of c/o's are 8/6 to which many consider and suggest might be too stiff for daily driving on NYC/NJ roads. 8/12 or even 8/10 would be considered VERY stiff on a 240 and certain not suggested for daily driving (I don't think i've even seen spring rates that are higher in the rear then in the front for 240's). My question is why is a car like a RSX with those springs rates not nearly as stiff as a 240 would be with the same rates? I was hoping to get a good or close enough example of how my s14 would feel with 8/6 rates by driving in his car, but with the higher rates on the RSX, that threw my little experiment for a loop.

06-06-2005, 10:31 AM	#2
Var Post Whore! Join Date: Sep 2003 Location: Norcal Age: 42 Posts: 5,032 Trader Rating: (0) Rides Gallery: Var Feedback Score: 0 reviews	Cars with double wishbone suspension have a different effective springrate. You'd need a stiffer spring to get the same feel on a double wishbone. I dunno much about honda's but the RSX may have a rear stiff setup to counter understeer. The comfort level in a car is ALL determined by the rear spring spring rate and shock valving. I have Tein HA's. On a soft setting, they are really comfortable, and on stiff, still daily driveable. 2 different coilovers with the same spring rates can also be dramatically different depending on shock valving. Basically..spring rates dont mean much. It's all in the shocks. WHat kinda coils are you interested in buying? __________________ Hi

06-06-2005, 10:35 AM	#3
DocTaDrifT Zilvia Addict Join Date: Oct 2003 Location: Montebello Age: 37 Posts: 966 Trader Rating: (0) Feedback Score: 0 reviews	i have kei office coils on my car and its so stiff i was gettin sick after driving when i first got them hahaha __________________ 09 VW GTi S14 not so daily driver

06-06-2005, 10:41 AM	#4
orion::S14 Nissanaholic! Join Date: May 2003 Location: Orange Park, FL Posts: 1,666 Trader Rating: (0) Feedback Score: 0 reviews	A lot of it is in the shocks (ride comfort and smoothness)... And as it has been said here...the "wheel rate" of a MacPherson setup is the spring rate (8K spring rate = 8k wheel rate). On a Honda (double wishbone), a 10k spring rate will most likelybe a 5k wheel rate. See the difference? It all depends on suspension geometry. - Brian __________________ www.KA24DEvelopment.com

06-06-2005, 10:48 AM	#5
95Blue240sx Post Whore! Join Date: Jul 2002 Location: Girls pee-pee when they see me Age: 40 Posts: 4,084 Trader Rating: (0) Rides Gallery: 95Blue240sx Feedback Score: 0 reviews	Finally a good question that im happy to read. Anyways it makes a lot of sense. I have HA on my car with 6/5 rates. It set really soft and it still feels everybump on the road. I dont get how some people ride with 8/10 + setups. CRAZY. Good question though. __________________ Please leave me feedback

06-06-2005, 10:50 AM	#6
pruto Zilvia Addict Join Date: Jan 2003 Location: Los Angeles Age: 42 Posts: 982 Trader Rating: (1) Feedback Score: 1 reviews	geez people, we say this EVERYTIME the question springrate vs. comfort comes up: ride comfort for a coilover is dependant on spring rate AND valving. 8/6 on a tein feels different than 8/6 on Kei's office at the track, it also feels different on the street as well. also stiffness is dependant on other suspension components as well, how stiff or mushy the arm joints. my 9/7 on my apex'i N1 pros felt amazing on the street when i first got them. The ride got worse when i replaced all my rear arms and worse still recently when the shocks are starting to go out. as for other cars, spring rate choice is sorta based on suspension geometry and the weight and weight distributions of cars. Most double wishbone FF hondas have standard coilover rate of like 8/5 or something since most of the weight is up front. 350Zs on the other hand have a higher standard coilover spring rate than 240s at least partially because of the extra weight. anyway, to keep pounding the point in. By riding in a car with coilovers, you can not acurately judge the comfort level you should expect in your car with a different set of coilovers, even if it is the same spring rate. __________________ Paul Black and Red

06-06-2005, 10:50 AM	#7
WongFeiHung Zilvia Member Join Date: Jun 2003 Location: Dallas, TX Posts: 221 Trader Rating: (0) Feedback Score: 0 reviews	The solid RSX chassis probably makes it "feel" more comfortable also... __________________ www.projectnissan.com

06-06-2005, 01:52 PM	#14
killjoy Zilvia Member Join Date: Sep 2001 Location: San Antonio, TX Posts: 215 Trader Rating: (0) Feedback Score: 0 reviews	This link shows a load of useful info on suspension and also shows spring rates for almost every manufacturer. http://texas240sx.com/forums/showthr...?p=677#post677 __________________ stolen s13 new stock non-stolen s13

06-07-2005, 03:27 PM	#18
Var Post Whore! Join Date: Sep 2003 Location: Norcal Age: 42 Posts: 5,032 Trader Rating: (0) Rides Gallery: Var Feedback Score: 0 reviews	hey..stupid me for never checking. The tein HA come with 6/5 springs, not 8/6. No wonder my shit is so damn comfortable. Anyways. I think you should go with the HA. __________________ Hi

06-08-2005, 09:27 AM	#20
Var Post Whore! Join Date: Sep 2003 Location: Norcal Age: 42 Posts: 5,032 Trader Rating: (0) Rides Gallery: Var Feedback Score: 0 reviews	any coil is available with. If they are discontinued that's too bad, cause they are an awesome street setup. Also soft enough to absorb fucked up touge's on softer shock settings and stiff enough to drift with. __________________ Hi

06-09-2005, 06:38 AM	#22
orion::S14 Nissanaholic! Join Date: May 2003 Location: Orange Park, FL Posts: 1,666 Trader Rating: (0) Feedback Score: 0 reviews	Camber plates are(were?) included with HE's....but not HA's. - Brian __________________ www.KA24DEvelopment.com

06-09-2005, 07:18 AM	#23
TheTicTac Zilvia Junkie Join Date: May 2002 Location: CA Posts: 449 Trader Rating: (0) Feedback Score: 0 reviews	hmm? I've always thought that the reason that FF have higher rates in the rear was to keep the weight transfer at the front longer. It never occured to me that wheel rates or suspension geometery made a difference, learn something new everyday. __________________ GorgeousGarage L.oose S.ocks D.aisuke !

06-09-2005, 07:55 AM	#24
MakotoS13 BANNED Join Date: Jan 2004 Location: Texas Age: 41 Posts: 4,205 Trader Rating: (0) Feedback Score: 0 reviews	GRAN TURISMO. ever try to tune a fwd car vs a rwd car in that game? the reawr is stiff as hell cause all it does is basically keep the car steady. they NEED stiff rear to help induce oversteer. with rwd cars you have tires that actually do something in the back so the situation is changed dramatically because you now need the body to sit back on its "haunches" under acceleration but not so much that it gets sloppy in a turn. idunno, i just figure tuning a FWD car is a lot easier due to these observations.

06-09-2005, 10:47 AM	#26
orion::S14 Nissanaholic! Join Date: May 2003 Location: Orange Park, FL Posts: 1,666 Trader Rating: (0) Feedback Score: 0 reviews	Never heard that they were discontinued... See here: http://www.tein.com/nissan.html - They're still listed for S14. HE's were supposed to be replaced with some other "drift spec" coilover...and they are no longer listed there. - Brian __________________ www.KA24DEvelopment.com

06-09-2005, 11:38 AM	#28
axiomatik Post Whore! Join Date: Dec 2003 Location: ATL Posts: 4,697 Trader Rating: (0) Feedback Score: 0 reviews	There are several reasons why FWD cars have stiffer springs in the rear. First, a stiffer rear spring will reduce weight transfer on acceleration, providing more traction to the front wheels. Second, FWD cars are very nose-heavy, creating more understeer. A stiffer rear suspension reduces understeer and makes the car more neutral. Also, to address an earlier question, there isn't really an 'ideal' damping level for a given spring rate, since so many people drive so differently and have different ideas on how their car should handle. However, there is an optiomal range. If a damper is too weak (for example, when your shocks are blown), the spring will continues to oscillate for several cycles after hitting a bump, causing unpredictable handling. If a damper is too strong, it will take the spring too long to return to its equilibrium position after hitting a bump, again resulting in unpredictable behavior.