edit:
For those who just join this discussion...
Helper springs is NOT Tender/Assist springs. Please don't mix these terminology up.
Read this to learn about helper and tender.

After couple of hours of research, this is what i came up with, see page 2
/end edit



Current setup:
- KYB AGX
- Tanabe GF210 (4.1kg/mm, 2.6kg/mm)

Thoughts:
- 1.5" drop, Handles great, I love the current setup, however it still understeers under hard cornering, so a little bit less under would be perfect. After 5 years of usage, the ride comfort had decreased significantly... to the point i can't bear it anymore, driving on the shitting roads here is NOT FUN anymore.

Next setup:
- Progress CSII coilover shocks
- FRONT: Tanabe PRO210 TP656K150 (6kg/mm)
- REAR: Tanabe PRO210 TP655K150 (5kg/mm)
- All 4 corners: Swift Assist A65-068-040 (4kg/mm)
- eBay extended top hats (optional)
- Will raise it to 1.3, function over form, plus i like the look with some fender gap, more balanced.

Reasons:
- CSII coilover replacement shocks is cheap ~70$/ea, and they handles 250-500lbs. (optimal is ~300-350lbs)
- Shorter body than AGX or Koni yellow, should be more suitable for lowered car
- Almost the same piston size as Koni (36mm), CSII is 35mm.
- Need a better ratio on the spring to further reduce understeer, old setup is almost like 1/0.63 ratio, new setup is 1/0.83, so i should get less under.
- I had Tanabe springs before, and they are great, ZERO sag, the PRO series are not that expensive and have a wide selection of size and kg/mm. So i chose them again.
- Swift makes 2 type of springs, assist and helper, helper is just to keep the primary spring seated, assist however, do a little more than that, it also acts a little as primary spring. The one i am chosing is 4kg/mm which will be close to the stock rate of my Integra. COMFORT IS IMPORTANT... because roads here looks like this like 70% of the time:



Questions:
- What will be the effect of the assist springs on the primary springs?
- Will the assist fully compress first before the primary takes over? or will they both begin to compress and the assist will reach its max stroke first?
- Since my assist's ratio is 1:1, i believe my initial turn in should be good, at least similar to ITR (ITR fully compressed also have ~4kg/mm, and is also 1:1), what is your input on that?

Thanks.

 

Honestly a front sway bar would do a lot more to reduce under-steer. Mine sure did.

If going with a progress setup, I'm sure for a fee they'd make you custom rates. I've had my CS-II for 9 months now and they're like new.

Sounds like you could go with the 350/250 setup they sell off the shelf, however.

Again, getting sway bars (if you don't have them) would do a lot more for the car.

I've got 22mm front and 22mm rear and the car has very minimal under-steer on the autocross courses I've frequented.

Lastly, I'm 99.9% positive tanabe springs won't work with CS-II's. You can PM the Progress dealer in the marketplace and ask, but they can just make you custom rates.

 

No, front sway bar does not reduce understeer. Rear sway does. Integra already come with 24mm front sway (same as ITR) and i have already upgrade my rear to 22mm with ASR brace. A bigger front sway bar will however improve steering response (Mugen also sells 26mm for both front and rear). It is all about the final spring ratio in the end... if spring rate + sway bar gives higher rate at the back, it could reduce understeer.

I emailed Progress 2 months ago asking their shock specification, and they told me that their shock will accept standard springs with ID of 2.5" and height of 8.75". So the springs mentioned in my post will fit, the overall height of the combined height would be 8.5", not too far away from their range.

I know my rates are close to the standard 350/250, but would like to include assist spring to help combat the insane/ridiculous roads here. Actually, now that you mentioned it, i will ask them to see if they could make custom spring of 6" tall... that way i could put in the assist in there...

But really this post, i'd like to get some feedback of people who tried assist springs.

 

I seem to get the impression that is the conventional wisdom, but I'm telling you I've done half the current autocross season with no front sway bar and a 22mm rear progress bar.

Adding the front sway bar a month ago changed that, I have no or very little understeer. Maybe My driving has just improved, but it seems like the sway-bar helped a lot too. It went from being easy to do and annoying, to hard to do and trivial.

Since understeer occurs when the suspension is active, how does the swaybar not play a role since it changes the acting spring rate?

 

I can't comment on the transition from no front sway to having a front sway.
I think this site explains it fairly well: http://www.houseofthud.com/cartech/swaybars.htm

Can someone else who use assist spring give their impression here? Thanks.

 

Adding the front bar, without changing the spring rates, increased the total roll resistance, which reduces body roll, which could be keeping the front tires at a better camber angle, which would decrease understeer.

If you want to compare front bar vs. none, you need to change the front spring rates to compensate for the change in total roll resistance. Otherwise there are too many variables to learn from the comparison.

 

That makes sense.

 

True, but one of the benefit of using the CSII is that it accepts the standard coils, if ever i want to upgrade or change the spring rates, i can in the future.
Also i figured the shock would last for at least 5 years with shitty road here, it'd come down to like 13$/yr or something...

And it looks like the Koni/GC combo is 1200$? Granted that's MRSP, so lets some HT vendor sell it for 800$...(which i doubt)? If i really want, i think could piece the whole thing for like 600$?

CSII x 4 = 250$
TEIN coils = 200$
GC extended top hat = 150$

Anyhow, I'm just really interested in finding out the effect of the assist spring.

PS: Assist spring is NOT helper spring. http://www.e30m3project.com/e30m3per...ings/index.htm

 

You seem bound and determined to be different, I don't think it's going to be good for you. You're finding very poor reasons to not use tried and true setups.

Why can't you change the spring rates on koni/GC? Just order new ones and sell the old. You can pick any rates you want with ground control.

The Koni/GC combo is $800. It's more like $950 anywhere but from THMotorsports, and it's certainly $1200+ with top hats, which are pointless unless you're absolutely slamming the car.

 

My primary goal here is to find the balance between performance, comfort AND cost. To do that, i need progressive spring rate, somewhat softer rate for shitty roads and higher rates for performance...

Look guys, I've heard enough stories and know that KONI IS THE ****~! I know is a good product. So many reputable coilover system out there, TEIN, PIC, AMR... but they all have static spring rate which is about 8k/6k setup (PIC offer 7/6 and 6/5 i think). 8k/6k is GREAT for roads in the US and at the track, I've driven to the US before, 80% of the roads there is like race track smooth (except around Detroit lol).

But you need to take into consideration here that, roads here is ****. Different environment require different setup, you need to understand that. People at the track runs 10k+ rates with road cage and is amazing, doesn't mean the same setup will work for DD with smooth roads, and the same goes with DD with SHITTY roads.

I hope with that said, you will understand where i'm coming from what why i want to go with assist spring in order to archive the progressive rate characteristic for my coilover setup. Different usage calls for different setup. Now, i just need to understand MORE on the effects of the assist springs, and hear from people who used it have anything to say on it, so that i could truly determine whether assist would be the right choice for the right task. This is still in my research phase.

Few points to note here:
- Standard coilover springs don't come in progressive.
- Koni is expensive and their combo is fixed rate.
- Money don't fall from tree, if i can save 400$ i will, the money goes towards the snail i need to purchase this winter.

@Libertariat: Actually, i am going to email Koni to see how much they sell for just the coilover body, or just their setup and ask for shorten springs (so i could just throw in the assist). Totally didn't think about that.

@solbrothers: 1000$ vs 600$ is a big difference, i agree with you that free replacement is good, but i don't believe the CSII will blow every year either. Assuming my 2 front shock could blow after 5 years, i could still replace them twice in 10 years with 400$, by then, i'm sure newer technology would've emerged, bigger piston or something... if i still keep my car for that long, i'd get the newer product instead. Bottom line is, the extra 400$ don't justify the cost right now.

 

Well, you don't need top hats. The Koni/GC setup with custom rates is $800 from THMotorsports. That is indeed not much mroe than $600.

I'd recommend my progress CS-II($600) for anyone who wants a mild drop and is in entry level autocross. Koni/GC($800) for the next up, and AMR($1200) for people really looking to compete.

Koni/GC and AMR are really the end all for "low end" suspension. There are plenty of suspension setups out there that are $3,000-$5,000. A lot of car enthusiasts are extremely jealous that civic owners have such a tremendously competitive market driving down prices of quality suspension.

$800 for arguably the best mid/high end suspension setup with totally customizable spring-rates and re-valvable shocks is a a downright steal.

 

Yea, hence why i put tophat optional in my first post. I will also keep the Koni/GC setup in mind. Another thing to note is the CSII have shorter body than the standard Koni yellow.

I will pm THM right now to see what kind of setup I could get from them...

 

What's the advantage of the shorter shock body?

There isn't one. At least not regarding the consumer decision you're trying to make. It's a different design with ups and downs.

 

Look i'm not going to argue with you with other side topic, please just focus on the topic (assist spring) that I raised. Thank you.

To answer your question... With a short body design, your shock won't be bottoming out compared to shocks with longer body. This is exactly the same reason why Koni designed their SRT.T (orange) with shortened shock bodies. There is no downs if you lower your car and uses shorten shock.

The yellow series from Koni had been there for over 10 years+ (if not more), it is highly unlikely that they will redesign the yellow to use the new shorten design. Plus Koni Yellow is also widely used in many OEM application where people may not drop their ride height at all, the cost of redesigning the Yellow would be huge for Koni.

 

Jesus, what's wrong with you, if you read my QUESTIONS in my first post, i only ask for feedback on the assist springs (from people who used it) and the effect of the assist spring, i didn't ask for opinion on which is the best off the shelf suspension combo to get.

Which part of, "no one setup fits all roads", do you not understand? Obviously I've read everything that had been posted thus far, and obviously i DON'T THINK that your recommendation will suit my needs.

I'm done with HT, thank you.

 

this thread is 19 posts deap and no one has any info on these assist springs that codenamezero is trying to find out about. Everyone and their dad knows about koni yellow and ground control, yeah they good whatever. Once someone tries to do something different to benefit THIER NEEDS people tell them its not a good idea and buy ground control and yellows. fak that hondatech

 

"Assist springs", I've never heard before.
"Tender springs", I have.

The basic theory is to couple a pair of springs to achieve a somewhat progressive rate. Somewhat, because you have 1 rate (main + tender in series) until coilbind is achieved on the tender, then a different rate afterward (just the main).

The complexity of such a system is beyond what most amateurs are willing to play with. There won't be a lot of information on here about setting that up.

The biggest difficulty in tuning will be determining the amount of tender spring travel needed such that the system transitions from the softer rate to the stiffer one under the right conditions. Defining "the right conditions" will also pose a challenge.

 

Please dont give up on this thread codenamezero!! I read your posts and you are on point so far IMO. You are using formulas to calculate what happens in the suspension, you are weighing positives and negatives of different situations using different parts/combinations....and you have a firm goal in mind. You are leaps and bounds beyond the "noise" being posted in this thread. I find that users like "libertariat" owe their information to the "he said, she said" crowd rather than the technical aspects of whats REALLY going on. (I say that not as an attack, but rather just pointing out the obvious because some of the info he has provided, is just flat out wrong.)

Unfortunately i dont have any first hand experience or information regarding the assist springs you are looking at, but from a technical standpoint...as long as the calculations work out in a favorable dynamic load ratio (You will have some math to do, in order to see what impact the assist springs will have under load) I think your idea will work great to accomplish the goals you have. I am leaning towards that setup being linear under compression (i feel as if the assist spring will compress completely, before the main spring comes into play due to highly varying rates between the 2 springs) But under de-compression thats where the springs will act in a progressive fashion. So the valving on the shocks is going to be a key factor IMO. I think keeping in close contact with the shock MFG will pay dividends because they can calculate/create the right valving to work with your semi-progressive spring setup. Good Luck, and keep posting the information you come across! Different is good

 

Tender spring on top. Notice the flat sides to keep things straight under coil bind. Standard Eibach ERS on the bottom, like those that come with GC sleeves.

 

H&R Ultra lows sit at around the $800 mark.
Has your helper springs

I guess those small springs are nice because you wont get clinking from your suspension with the springs moving around when your low.

They only do a mild drop? Short body and adjustable? How is it all the way down then, do you have any pictures?

 

Helper springs are different than tender springs.

A helper just takes up slack, to prevent springs from unseating. They make no change to the no effective rate of the suspension, and are fully collapsed (coil bind) with just the weight of the car.

A tender spring stays active (not collapsed) with the car's weight, and does contribute to the effective spring rate, at least at the start of suspension movement.

 

For the drop, calling something mild is subjective. The body is short, and progress wouldn't recommend going lower than my car sits. The car rides great with the 350lb/350lb setup. A front sway-bar was definitely much needed.

 

16" wheels?

I have a slow car, nothing better to do that drive slow and slammed :\ I want to try 1/2 inches off the ground
why no lower? just because they dont recommend it? Could have the guy make a custom setup then I guess :\ more $ though

 

After 3 hours of digging on the web, I've realized the way i interpreted the tender springs was wrong. It turns out in order to archive the initial spring rate that i want (around 220-250lbs) i will need to use 350lbs (tender) and 600lbs (main). These are the formulas:

IR = (MR * TR) / (MR + TR)

Where,
IR = Initial Spring Rate
MR = Main Spring Rate
TR = Tender Spring Rate

From my understanding (correct me if i am wrong), lets say I want archive the comfort of a stock Integra (~220lbs), so IR = 220. My choice of tender spring is quite limited from Swift, the stiffest they make is only 6kg/mm (350lbs), so TR = 350. Solve for MR and I get... ~600lbs.

In a nutshell, this is the example that I read while doing my research and it explains it really well:
So I would get roughly 220lbs initial spring rate, the rate would increase as the springs compresses, when the tender spring is fully collapsed... the main spring takes over, archiving its 600lbs rating. For the rear spring rate, just doing it quick quick, i could go with something like. 350lbs tender, and 500lbs main, this would yield 206lbs initial spring rate.

Final result should be...
Front: 222-600lbs
Rear: 206-500lbs

edit:
BTW, the nice things about dual spring setup (tender/main) is that, you can set any final rate, and only increase the tender spring as the variable to archive your initial spring rate. Say, if I think 600/500 is too much, and I only want to settle with 400/300, then all I need to do is to increase the tender spring.

Example:
500lbs tender, 400lbs main = 222lbs initial front
650lbs tender, 300lbs main = 205lbs initial rear

I believe only Eibach sells tender spring with those rates. But I can't find their catalog yet.
/end_edit


With all that being said... in the last couple of hours, I've also have a couple of email exchange with Koni. Lee Grimes from Koni was extremely resourceful and helpful, after a couple of email exchange with him. He suggest me to buy a pair of Koni yellow and replace my existing KYB AGX, see if this would cure the harsh ride I have (since i had the AGX for 5 years, they might very well be fully blown...). I guess i was too focused on getting some coilover setup that I've totally forgot the simplest thing to do... Which is just replace the shock... lol.

Lee told me that Koni yellow should have no problem handling the GF210 (which i have no doubt, since the standard combo comes with 350lbs). In addition, Lee also showed the possibility to upgrade the Yellow with the coilover sleeves that will accept the standard 2.5" springs to do the coil + tender springs in the future.

So after all that, I will most likely just get 2 Koni yellow shocks for the front, swap it out for the time being and see if it gives me back the comfort. If I can live with it, the rest of the money goes to my turbo.

Otherwise, my plan would be Koni Yellow + coilover sleeves kit + the spring rates i mentioned above.

Experts out there, let me know if my findings above is wrong, i'm still learning/researching. Thanks.

These are the references that I got during my research on dual spring setup:
http://pirate4x4.com/tech/billavista/coilovers/Part_1
http://insideracingtechnology.com/eibach3.htm
http://forums.evolutionm.net/evo-tir...ing-rates.html
http://forums.rennlist.com/rennforum...pension-1.html

 

If you are looking for comfort, you would want to put the fresh shocks out back.

I am by no means a expert in suspension, but I do know the rear has much more of an affect on comfort then the front.

I can't really speak to the tender springs question, as i have no experience with them, and have never really looked into or at them.