What is the purpose adn function of "helper springs"

This week, I received my set of ARK ST-P coilovers. I was surprised they have little springs installed under the main springs. It doesn't show these in any of the ARK advertisement pictures.
What is the function of these, and do they fully compress under the load of the car. If so, it'll be very hard to set the height on these (as you don't know their length, once the car is resting on them).
Also I was surprised to find, that fornt and rear are as good as identical. The front ones are the longer ones (approx 1 inch, spring and assembly).



Any insights on the function and install of the coilovers would be appreciated.

they keep the springs from falling off the perches when you jack up the car

I would double check which ones are F/R because the NSX almost always has the longer spring on the rear.

CL65 Captain said:

I would double check which ones are F/R because the NSX almost always has the longer spring on the rear.

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That sure sounds correct to me.


Back to the original question....

The springs on these are pretty stiff. So when the suspension is in full droop, the springs total extended length is shorter then the travel of the shock. The helper spring takes care of the slack, so the springs do not rattle, and keeps them from slamming back into the perch when the suspension comes back up.

The helper springs fully compress under load, and it is no harder to set corner balance or height with them vs. without.

HTH,
LarryB

If I didn't double check it allready, I wouldn't post it. The longer ones are labelled NA1 F, and the shorter ones NA1 R. Who's wrong, ARK, or us.

So for setting the ride height, I have the substract the height of the helper spring from the total coilover length? Sounds like it'll take quite a few times of trying before I'll have the wanted ride height set.

The longer springs may be in the rear but the rear shocks are shorter than the fronts. It's just that the rear perch is significantly lower than the front perches which leads to the longer rear spring.

I'd be worried that at full droop that the front springs may rub the upright.

CL65 Captain said:

I would double check which ones are F/R because the NSX almost always has the longer spring on the rear.

Click to expand...

For 'most coilovers' that have zero droop travel, and minimal shock travel, the fronts are shorter than the rear. For JRZ and KW, often the fronts are LONGER than the rear. Look at post #3:

http://www.nsxprime.com/forums/showthread.php?t=124373

W said:

The longer springs may be in the rear but the rear shocks are shorter than the fronts. It's just that the rear perch is significantly lower than the front perches which leads to the longer rear spring.

I'd be worried that at full droop that the front springs may rub the upright.

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That is a valid point. The springs on the ARK (which are thick in diameter and have a lot of winds -which are usually from a really high spring rate, poor metallurgy in the spring, or a combination of both) look very long and if the front spring perch is too low, it could rub on the upper control arm.

I'm suprised to see that ARK even has helper springs. I've also heard mixed reviews from somewhat credible resources but have no personal experience with them myself. I will say that the helper springs (which signify more droop travel than most coilovers - a good thing - means as others have said, there is more droop travel than purely uncompressing the spring alone) this means that helper springs do hold the main spring in place, preventing it from jamming, binding, etc... and keeps constant load on the spring/perch when hitting a big bump or jacking the car up.

Most suspension companies give a baseline or operating range of ride height to pre-set the coilovers before installing.

You measure ride height from the lower eye-bolt (that bolts the bottom of the coilover to the lower control arm) to the BOTTOM spring perch (the top of the bottom spring perch that the spring sits on) -which determines the arbitrary ride height of the car. The biggest thing is make the Right and Left sides of the front and rear even -which is often fairly close in terms of corner balancing the car.

Id be suprised if ARK or any coilover company dosn't have a recommended baseline or operating range that you can measure before installing it. If it dosnt, then just install it, see where the ride height is at, then raise the right and left evenly and the amount you need front to rear for your desired ride height. Bear in mind that the springs often will 'settle' in the first few days to weeks and will lower 1/4-1/2" and might need to raise the car back to your desired ride height after.


Billy

FXMDBilly said:

For 'most coilovers' that have zero droop travel, and minimal shock travel, the fronts are shorter than the rear. For JRZ and KW, often the fronts are LONGER than the rear. Look at post #3:

http://www.nsxprime.com/forums/showthread.php?t=124373

Click to expand...

Hey Billy, if the fronts are on the Left (which looking from the brake line holder they are) they are about an 1" shorter than the rear. Measured with Photshop.

My JRZs are shorter on the fronts (spec'd per Frank Chen @ JRZ).

F - Hyperco High-Perf. Chassis Springs, 2.25" I.D. x 6" x 600lb
R - Hyperco High-Perf. Chassis Springs, 2.25" I.D. x 8" x 500lb

When I was on Comptech Pros they were the same length F/R. 8".

DROOP, is that in an English dictionary? If someone can explain "droop" for me, I'll start reading again from the top of the thread.

thanks,

"Compression" is the shock at the shortest distance.
"Droop" is the shock at the longest distance.

Regards,
LarryB

CL65 Captain said:

Hey Billy, if the fronts are on the Left (which looking from the brake line holder they are) they are about an 1" shorter than the rear. Measured with Photshop.

My JRZs are shorter on the fronts (spec'd per Frank Chen @ JRZ).

F - Hyperco High-Perf. Chassis Springs, 2.25" I.D. x 6" x 600lb
R -Hyperco High-Perf. Chassis Springs, 2.25" I.D. x 8" x 500lb

When I was on Comptech Pros they were the same length F/R. 8".

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I must have been tired last night. I was answering/agreeing with "W" that the shock length is longer in the front than the rear while replying to you about the spring length. :redface:

Yes the front springs are almost always shorter than the rear. KW: 170mm front, 200mm rear. (FXMD optional 140mm front spring).

Billy

Mikevd said:

If I didn't double check it allready, I wouldn't post it. The longer ones are labelled NA1 F, and the shorter ones NA1 R. Who's wrong, ARK, or us.

So for setting the ride height, I have the substract the height of the helper spring from the total coilover length? Sounds like it'll take quite a few times of trying before I'll have the wanted ride height set.

Click to expand...

Measuring and setting length may only get you in the ball park. You will need to set the ride height after they have been mounted.
You should get the car aligned. You camber and toe may have changed if the car was lowered.

Later,
Don

For the NSX, the front springs have to be short to clear the upright at full droop unless you have shortened shocks or run super soft springs or run a higher ride height. I don't think even long 2.25" ID springs will clear because the NSX has quite a bit of droop range in the front and as the shock extends it gets pulled in towards the upright. There is basically a minimum distance between the lower shock bolt/eyelet and the bottom of the spring perch. That's why we have to run ~7" springs up front when running stiffer springs.

W said:

For the NSX, the front springs have to be short to clear the upright at full droop unless you have shortened shocks or run super soft springs or run a higher ride height. I don't think even long 2.25" ID springs will clear because the NSX has quite a bit of droop range in the front and as the shock extends it gets pulled in towards the upright. There is basically a minimum distance between the lower shock bolt/eyelet and the bottom of the spring perch. That's why we have to run ~7" springs up front when running stiffer springs.

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Dont you mean clear the upper control arm, not the upright?

Why do you have to run 7" springs up front?

FXMDBilly said:

Dont you mean clear the upper control arm, not the upright?

Why do you have to run 7" springs up front?

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Nope, I do mean the front uprights. I couldn't find a parts diagram but you can see them in the following post by titaniumdave.

http://www.nsxprime.com/forums/showpost.php?p=803596&postcount=15

These are what the upper and lower a-arms attach to. If there's a clearance issue with the upright, the lower spring perch will contact the upright right by where the upper a-arm attaches. This probably won't happen in most real life circumstance unless you're changing out your shocks or jumping your car over things.

I run a 7" front spring because that's what someone was selling and it seemed to be a usable length. I had previously used 6" springs with tenders. I just like to experiment with different setups to see how they feel. Any feedback is appreciated.