Jeff Curtis

...WTF??

So, WHO makes the "best" spring for the $$$$$??

If you go to one of the most popular "domestic" spring manufacturer's website (Hyperco) they boast that they use the "finest coil wire available" and have quality standards that would rival Taco Bell!

For that matter, what's the difference between 8" coils and 9" coils of the same PSI rating?

...how 'bout 2.25"/2.50" I.D.??

WHY is that that stock cars (American) tend to use 2.5" I.D. and European cars seem to, for the most part, use 2.25"??

Am I looking too far into this mess??

Okay...the reason why I ask is because recently I fell upon a deal, one that you just couldn't shake a stick at.

I bought a set of custom valved Bilstein HD shocks, NOT full threaded, but partially threaded...in "like new" condition...and they were!

With them came a plethora of springs:

1) a set of 4, 9" Hypercoils - 2 - 750# and 2 - 600#.

2) a pair of 8" H&R springs ~ 600# and some change (metrics)

3) a pair of 11" H&R springs ~ 750#, and some change (metrics again)

The Hypercoils are 2.25" I.D. and the H&R springs are 2.5"

With the "deal" came several sets of perches, lock rings, spacers and hats, some 2.25" I.D., some 2.5".

SO, I can have just about any combination that I want.

I initially installed the Hypercoils and after a weekend at the track, would like to try an 8" - 500# set in the front...so I can get my front end a bit lower, and reduce some understeer (w/100# less). Currently, with the 9" springs, the front end is about .5" shy of where I want to be and the perches are screwed all the way down to the bottom of the threads, with lock rings delete.

Would there be a different reaction rate for the shorter 8" springs??

Would there be a difference between 2.25" and 2.5" I.D.??

Does anyone have a pair of springs that they would like to "trade" for a set of mine that they wanna try out? These are just the typical linear springs, but as mentioned, I have several shapes and sizes...both sets are 600#/750#.

The previous owner of the setup says that he started with the H&R 8" (600#) springs in the front, and the 11" (750#) springs in the rear, but didn't like the idea of the different length springs.

So he had spacers made for the rear shocks and used a matching set of 4 Hypercoils with the aforementioned length of 9".

This made him "feel better" about the setup. I agree, I tend to be that way too!

Is this justified or just a self-created "theory" that different length springs will react differently with each other, etc.

My plans are to leave the rear 750# Hypercoils in, with the "handy-dandy" 2" spacers that were machined for them so the car has a reasonable ride height. The car feels great, but I'm at the point where I want to "tune" my suspension, thus the decision to go 500# in front.

(am I giving away my "secrets" here??)

After the initial install, my first inclination was to buy a pair of 8" Hypercoils, 500# rating and try them out, heck...the cost is NOT prohibitive of "experimenting" - is this wrong??

I take that back, my first inclination was to put the 8" H&R springs in to verify that my front end height adjustments would put me in the ballpark of where I wanna be...but that would mix H&R 8" 2.5" I.D. fronts with Hypercoil 9" 2.25" I.D. rears - it seems that would yield a "goofy" combination.

...and the fronts would still be 600#, as a matter of fact a bit more, like 638# or something crazy.

I hope I've made some sense, doubt I have...but any input is welcome. It's late, I've rambled on enough.

I guess a call to Hyperco is in order?

JC in NY

As far as I'm concerned a spring is a spring, so mixing brands should not be a problem.

That said, I'd shudder to have an Eibach in the front and a Hypercoil in the rear.

Jeff Curtis

J.C. - ...my point EXACTLY!

Okay, I had some time to think of the "babble" I wrote previously...decided I might want to "focus" my question(s).

Basically, is there a difference if you have say a 9" spring, 2.25 I.D. and rated at 600# and you have another spring, 8", 2.5" I.D. and rated at 600#??

Will they react differently, given the same travel of the shock, weight of car, etc.??

I'm pretty much convinced I just need to order a pair of Hypercoils, 8" to lower to MY specs and at a 500# rate to reduce understeer. The I.D. would be the same as the current 9" spring, at 2.25".

I will likely contact Hyperco, prior to making the purchase to get some tech advice on whether mixing 9" springs rear and the difference between an 8" and 9" spring.

Your thoughts, opinions and general statements towards how FRIGGIN' NUTS I am will always go appreciated.

Mike Buck

Fell upon . . . with a bit of help

I think you are the right path going with shorter springs. Turning the spring perch to the lowest possible setting is not a good idea. I'm far from an expert, but I believe you want to the perch set as high as possible, while still maintaining the ride height you want. The higher the perch, the more damper travel you'll have . . . a good thing.

I really like the suspension setup I have now. Custom Bilstein Cup coilovers with 8" 2.5"ID Hypercoils on all four corners. This gives me the flexibility to change rates F/R if I want without the need to buy 4 new springs. Perhaps I can just buy 2 new springs and move the fronts to the back, etc... The 8" springs also let me set the ride height where I want it, but without turning perches all the way down. My front perch is set within an inch of its highest possible position, which gives me a lot of damper. Anything less than 8" will probably require some sort of tender/helper spring setup to acheive a reasonable preload.

As I understand it, Hypercoils are known to test more consistnetly to their stated rate than other brands. I'll stick with them until I find a better reason not to

Cya at the Summit Point Club Race

Jeff Curtis

Yes, Mr. Mike...YOU ARE THE MAN!

I still remember getting the "tip off" and going nuts until I received a reply.

I'm glad I took the plunge, worst case scenario, I get sick of the stiff setup and just put in weaker springs. Although, I have ran a few errands in my car and taken it to work a few times - it's not that bad.

Thankfully I know the town, with all of it's dips and potholes, sharp parking lot entries, etc. - so I'm getting along pretty well with the stiff setup.

Every now and then I hit a good "whoop-dee" in the road and man, does the car REACT.

I got a reply from the Tech Dept. at Hyperco today, they say it's NO problem to have different length springs when you're running the "free length" springs, which is what these are categorized as.

8" 500# springs, here I come! ...anybody wanna sponsor a racecar?

Jason @ Paragon Products

The length of the spring won't make any difference in how the spring reacts or the amount of stroke a shock will have at any given ride height. The only difference between say a 10" spring and a 8" spring of the same rate is going to be the distance traveled to coil bind.

M758

Jason is right on.
A coil spring is a coil springs.

Most important factor is spring rate obviously.

Length of the spring then impact ride height for a fix perch. So go 1" longer spring and get 1" higher ride height. Of course by adjusting the perch you can down 1" you can get a same ride height.

Damper travel is determined by directly by ride height and indirectly by spring length or perch height. (see above)

The only reason not set a perch at is limit (max or min) is to allow room for fine tuning for corner balance. If you are already at the stops then have little fine tuning room.

Coil bind is the only time spring length makes a difference. A longer spring will allow more travel before coil bind. Coil bind in general is not a good thing excpet for helper springs as it makes the spring rate of the car very non liner. It can instantainiously go from 600 lbs-in to 500000lbs-in if the coil binds. The effect is similar to bottoming the car.

Jeff Curtis

...maybe someone can advise me on what's the deal with the "helper or tender" springs.

Here's what I've gathered they're used for, and if in fact I need them, I wanna know!

When I jackup the front wheels of my car, the springs drop off the hats at the top of the shock, several inches, especially if I release my swaybar.

When I lower the car back down, sometimes the coils POP back into place, as they aren't aligned just right when lowering the car...so I try and get my arm up there to "guide them".

As my perches are screwed all the way down, at present, with 9" springs and the front end is about 1/2" too high, I am going to change to 8" springs and also lower the springrate.

DO I NEED TO GET 7" SPRINGS OR SOMETHING if I want to run the "helper" springs??

I take it that these things keep everything aligned, especially on those hard turns where you might get a front wheel off the ground, then upon "touchdown" the spring isn't aligned just right and it "POPS" back into place...I would imagine this could cause high speed issues??

SO, should I get a spring that's even shorter than 8" if I want to get the "helper" spring setup?? If so, what rate of "helper" spring do I need??

Another angle on my question, if 8" springs alone would satisfy my requirements for height adjustment, what length would I need to go if I wanna add "helper" springs in order to keep my springs aligned when "up on three".

I know there's a collar that goes in between the main spring and helper spring, but how much space does the helper spring takeup when compressed?? Being that the coils on the helper springs are FLAT in between, I assume this is because they are at full compression when car is on the ground??

I'm guessing the "tender" springs are another animal...could it be that they make your spring combo progressive??

My WHOLE life is going to be dedicated to finding the answers!!

Am I even close to guessing what these little gems are used for??

Jeff Curtis

...and you thought I actually WORKED at night??

Could this be the definitive answer to my excessive questions??

http://e30m3performance.com/tech_art...-tech/springs/

This was actually a VERY comprehensible explanation on the helper/tender spring subject.

I'm convinced that this is what I need...supposedly the "helper" spring came about in Europe due to TUV requirements that the spring be fully seated, even when suspension was at full "droop".

They even explained how the "helper" springs usually compress to 3/8" and then I guess you would have to add the thickness of the spacer in between the main and helper springs in order to figure what length of main springs you would want to use?

I'm thinking 7" coils now (in front), with 3/8" helper and guessing that the spacer/coupler would be 3/8" and adding the lockring back into my setup to lock the perch in place after adjustment (3/8")...that's 1 1/8" of hardware added in there!

So, if 8" coils alone would solve my height adjustment issues, then 7" coils should be the ticket.

Makes sense.

Now if they could only make these for HUMANS! ...so our "springs" would be seated even when at full droop.

Bryan Watts

Unless you find that your spring/damper combo isn't stiff enough to keep the springs out of coilbind under hard cornering or when hitting a bump mid-corner. There's nothing worse than rear coilbind when hitting a bump in the middle of a 80+ mph corner and spinning without any idea why or any chance at catching it. I've seen guys chase problems for hours of testing, only to find out they were have coilbind issues and going to an infinite spring rate at inoppurtune times.

Then again, we experiemented with getting into the damper bumpstops on purpose under trottle on one of the cars I've driven in order to get the rear-end to rotate better...which was essentially like going to an infinite spring rate compared to the relatively low spring rates we were running.

Jeff Curtis

Bryan, I follow you COMPLETELY.

My spring rates are pretty stout, and the shocks are beefy as hell, re-valved Bilstein HDs, the version with the HUGE front shafts...crazy how much larger they are than the previous HD model.

I had coilbind with my previous setup, was apparently overdriving the setup, but sold it in good shape.

Jason @ Paragon Products

Jeff, remember that huge front shaft isn't actually the piston of the damper. The Bilstein is an upside down design so what appears to be a huge piston is actually the body of the insert and the piston extends downward in the strut housing.