steering and suspension Spring Rate Poll

[ClarenceTE72]

I'm still researching on what shock to use. The majority of my experience was setting up older toyota corollas. Specifically the ae86 chassis. I noticed that they have similar shocks so I'm considering running tokico hts shocks from the corolla in the e10 using swift coil over springs along with helper springs. My experience with tokico hts are great, they perform well on the track full stiff and can set soft enough to enjoy street driving. I'd like something adjustable, konis are an option too.

 

To my surprise, both the AE86 chassis and the E10 chassis are  closely similar in weight distribution and weight itself. Of course both cars drive differently. But its an idea I'm working on to see to build something different and more specific to my driving style. 

 

The ultimate goal is to build a pretty aggressive suspension for the mountain road/ track but yet just enough for street. I want to make it as nimble as possible with the least amount of roll without making it too stiff for the street.

 

Anyway, I just measured and I have about 26mm sway bars up front and 23mm in the rear. The car came with them when I bought the car. 

I plan to run 195/60/14 azenis tires for grip and 60 series tires should compensate for a more comfortable ride on the street.

 

I currently have 195/45/15 toyo t1r tires on bilstein sports and eibach pro kit springs. Its not bad. But I still have to refresh the bushings, maybe upgrade the front sway and go coil overs. I'm still in the planning process to put the pieces together. I just wanted opinions from experienced racers so that I can maximize the handling without sacrificing too much harshness on the street.

 

Thanks for the quick reply!

Edited January 15, 2015 by ClarenceTE72

[02TurboMI]

Phew...it's been over 10 years, but instead of starting a new thread I thought it would be better to continue this.

 

I'm looking for advice. Looking for a nice sporty street feel. Not going to be tracked.

 

Front & Rear Coilovers

Front: 300lbs/in 2.5" Springs + Koni Sport Struts

Rear: 350 lbs/in 2.5" Springs + QA1 DS601 Adjustable Shocks

 

What I'd really like to know is if that spring combo has treated people well with the Koni Sports in front.

Will it be too stiff for a daily street driver? If so, I'd go down to 250 FR, 300 RR.

[Son of Marty]

Subjectively this is way to wide a subject to cover here, what's just right for faqer A is way to stiff for faqer B, it would be like you buying your underwear brand because it fit your buddy so well. Your best bet would be to get a ride in as many 02's as you can find in your area.

[uai]

I really liked the progressive Alpina Spring I had in my car 35-65 kg/cm front and rear at standing position they were around 43 kg/cm = 240 lb/in
Right now I am at 80kg/cm front =450 lb/in but that is more track oriented.

[TobyB]

For 'sporty street' I'd be looking in the 200- 250 range front, unless your streets are smoother than ours.

300 was painful around here.

 

As to damping vs springs, I think 300 is going to be OK for Sports, until they start working hard and getting hot.

 

As to mixing and matching dampers, just be careful, and make sure not to go nuts on rebound damping in back.

 

I raced at both Pacific and Portland on 400 lb/inch springs  and that never caused much trouble.

Maybe a bit stiff for Pacific when it was so rough, and a bit soft at Portland, but changing springs never

found much lap time.

 

I agree with SoM, it's all so relative to everything

from ride height to seat choice to butt fat thickness that one person's

ideal is the next one's hell.

 

t

well- padded

 

 

Edited January 20 by TobyB

[wheelieking]

On 1/19/2024 at 7:58 PM, 02TurboMI said:

Phew...it's been over 10 years, but instead of starting a new thread I thought it would be better to continue this.

 

I'm looking for advice. Looking for a nice sporty street feel. Not going to be tracked.

 

Front & Rear Coilovers

Front: 300lbs/in 2.5" Springs + Koni Sport Struts

Rear: 350 lbs/in 2.5" Springs + QA1 DS601 Adjustable Shocks

 

What I'd really like to know is if that spring combo has treated people well with the Koni Sports in front.

Will it be too stiff for a daily street driver? If so, I'd go down to 250 FR, 300 RR.

 

I have the Ground Control kit with 350lb springs and Koni Sport adjustable dampers.  For street use I wouldn't want to go much firmer.  I haven't tested how many clicks the dampers are at, but I had the car aligned and corner balanced at a race prep shop and they did the adjusting. I might start playing with it this summer, but I need to do it methodically, so I can keep track of which settings are good/bad/best etc. 

[AceAndrew]

@02TurboMI  That's pretty spot on for an aggressive street car in my experience.  I prefer the 250-275 w/ 8" for a "firm but not stiff" street car.  If it was a bit more aggressive with an occasional autoX/track day, I'd go up to 300-350 w/ 7".

 

Just one point of context, when building the Clarion '02 it was specced w/ 250's and HD's initially.  Most of the drivers/media enjoyed the balance for canyon driving (I believe Mr. Macha and Mr. Danco here on the FAQ drove it), but then Chris Forsberg (excellent drift driver) drove it out on track and suggested stiffening the rates.  Swapped to 350's w/ sports.  Handled better and it was still livable on the street, but then the Clarion rep drove it and politely requested I put back in the original setup under the impression it was more in line of what they were after.

Edited January 23 by AceAndrew

[02TurboMI]

Speaking about Linear Springs specifically...

 

One point of discussion that I'd like to note, is the length of the spring should not impact the overall performance of the spring. "325 lbs/in" does not relate at all to the spring length, only to the resistive force of the spring during compression and expansion. The length also effects the spring travel (an 8in spring can compress twice the length of a 4in spring, assuming same rate).

 

I've heard a lot of talk about 7in vs 8in springs with different rates, and my brain started hurting remembering way back to my Dynamics engineering course in college. So a quick phone call to H&R confirmed, spring length does not affect overall performance (compression and tension).

 

There are some minor differences (i.e. load at block, block height, etc), but those parameters are outside of the the scope I believe we are discussing here. Also, this comment negates ride height adjustability with different length springs

Edited January 29 by 02TurboMI

[AceAndrew]

Yes, great explanation, loved dynamics ... however, as you note at the end... my inclusion of spring heights were in relation to the vehicle ride height and how that does affects handling.

Edited January 29 by AceAndrew

[02TurboMI]

On 1/23/2024 at 1:25 PM, AceAndrew said:

 then Chris Forsberg (excellent drift driver) drove it out on track and suggested stiffening the rates. 

 

Oh yeah, 3-time Formula Drift champion Chris Forsberg...no big deal. 😆

[TobyB]

Quote

One point of discussion that I'd like to note, is the length of the spring should not affect the overall performance of the spring. "325 lbs/in" does not relate at all to the spring length, only to the resistive force of the spring during compression and expansion. The length also affects the spring travel (an 8in spring can compress twice the length of a 4in spring, assuming same rate).

Yup, totally-

as long as the spring is in the linear part of its travel then length doesn't matter at all.  Neither does 'sag'-

if a 10" spring has dropped to a 9" free height, it will still have the same rate.

 

t

coil bind is bad.

[John76]

Almost here! 🙂

 

[Son of Marty]

I like spring rolls. Oh wait a minute where are my glasses. Oh, OK never mind🤯

Edited February 9 by Son of Marty