So I've been reading up about suspension lately and it seems coilovers generally perform a lot better than a basic setup because they use linear springs (and other factors) instead of the progressive design such as H&R sport line or such. Is there anyone that makes stand alone linear springs to be used without coilover setups?

I upgraded to some performance shock/struts when I first got my car, and didn't know much about them, and now I want to stiffen up the ride some more and lower it, which I would do by getting some aftermarket springs, as I don't have the $$$ for coilovers. Is there that big of a difference between a coilover setup and just general aftermarket suspension upgrades like shocks/springs?

Basically if anyone knows of some nice stiff handling springs I could use on my car I would be glad to know, and explain this linear/progressive thing. Also, comfort and daily driveability are not too much of a concern as I have other cars I also drive.

H&R Grp. G springs are stock sized and linear.

I'm still amazed at how people will spend big $$ to have a reputable engine builder develop and assemble an engine based on experience, research, testing, data acquisition, and plain intelligence, but they'll take a suspension setup that some company has developed and start chucking different parts at it with only their seat-of-the-pants as the measuring stick, or worse yet, just start asking around for free advice on the Internet and piecemeal an acceptable setup based on price, others' opinions, and *gasp* how "low" or "sick" the car looks. Ugh.

I'm still amazed at how people will spend big $$ to have a reputable engine builder develop and assemble an engine based on experience, research, testing, data acquisition, and plain intelligence, but they'll take a suspension setup that some company has developed and start chucking different parts at it with only their seat-of-the-pants as the measuring stick, or worse yet, just start asking around for free advice on the Internet and piecemeal an acceptable setup based on price, others' opinions, and *gasp* how "low" or "sick" the car looks. Ugh.

The people that spend big $$ on engine work are not the same people who do the other stuff that you describe.

I'm still amazed at how people will spend big $$ to have a reputable engine builder develop and assemble an engine based on experience, research, testing, data acquisition, and plain intelligence, but they'll take a suspension setup that some company has developed and start chucking different parts at it with only their seat-of-the-pants as the measuring stick, or worse yet, just start asking around for free advice on the Internet and piecemeal an acceptable setup based on price, others' opinions, and *gasp* how "low" or "sick" the car looks. Ugh.


All stock here :)

or worse yet, just start asking around for free advice on the Internet and piecemeal an acceptable setup based on price, others' opinions, and *gasp* how "low" or "sick" the car looks. Ugh.

Thought that's what the forums for :dunno asking others opinions on various topics.

And as I'm on a budget, price matters, otherwise I'd chuck the BMW for a Porsche.

And who wants their car looking like an SUV.

The people that spend big $$ on engine work are not the same people who do the other stuff that you describe.

You sure about that? :D

Thought that's what the forums for :dunno asking others opinions on various topics.

And as I'm on a budget, price matters, otherwise I'd chuck the BMW for a Porsche.

And who wants their car looking like an SUV.
Oh, sorry, I was PMS'ing last night, I didn't mean to make it sound like you were the target of my rant. I would recommend going with a proven setup from TC Kline or us, for instance, but you must expect to pay a bit more for a good combo. The reasons coilovers are better than regular shock/spring setups has very little to do with progressive versus linear springs. It mainly has to do with shock valving and other shock characteristics. That's the reason why tuned suspensions cost thousands. Good shocks are OK, great shocks are at least twice as expensive as good shocks. Take Bilstein and other OEM shocks versus modded Konis, JRZs, Motons, and Ohlins. The shock internals among the cheap brands versus the real racing shocks are not even comparable.

I put a set of H&R sport springs on a stress/strain machine once. They where for an e39 and advertised as "progressive" springs. There was a knee in the force-distance curve, but it happened just as the suspension bottoms out. So not progressive as you'd normally consider it. I didn't check, but I suspect that the suspension would hit the bump stops before that point.

Matched with Bil Sports, it was a nice street setup. But on a 540, you are only going to get so much out of a 3800 lb car.

Progressive springs normally are designed to stiffen up as a suspension approaches full bump. The conventional wisdom is that does funky things to car handling in a racing environment.

The biggest change to a proper performance after-market setup is in the damper. Linear springs are just easier and less expensive to manufacture. When tuning a car, the spring rates are matched to the damper valving to ensure the car handles properly - which includes not bottoming out on typical track undulations, etc. Which is completely different then not bottoming out on a driveway curb.

I'd call up a race shop or manufacture and discuss with them suspension setups and tuning options for what you want to do.

Progressive springs normally are designed to stiffen up as a suspension approaches full bump. The conventional wisdom is that does funky things to car handling in a racing environment.

Actually, most "real" race cars have progressive suspensions...they simply accomplish it by mounting the linear spring/shock inboard and using pushrods and various shaped bell cranks to create the progressiveness.

The problem with using progressive springs is that the damper can't be valved to control it as well. In the case of an inboard suspension, the damper can control the linear spring while the suspension geometry creates the progressive roll rate.

Yeah, forgot about the formula/prototype suspension geometries. I just had my sedan arm-chair engineer hat on. :)

Ha...you should see some of the "tricks" we used in the old Star Mazda cars with outboard suspensions. We literally shoved packers onto the shock shaft in order to create a progressive roll rate (albeit, not a smooth one) by using the bump stop as an additional spring. :)

...
Progressive springs normally are designed to stiffen up as a suspension approaches full bump. The conventional wisdom is that does funky things to car handling in a racing environment...

Depends what type of progressive spring we are talking about!!

On you typical "I want to lower my ride" spring, the main portion of the spring is close to a constant rate, with the softer portion of the spring used to compress easily (usually till coil bound) and provide a Lowered ride height and still remain captive when at full droop.
Your typical progressive springs:
http://www.mercurymotorsport.com.au/workshop/partinstall/kingsprings.jpg

Then there are progressive race spring that come in single or double ended and they behave more as you describe, we run these on our rally car (Evo II).
Where the whole spring is actively used.

These are the same shocks and springs (double ended) we use. IIRC the wire diameter is tapered for the progressive portions.
http://www.185performance.com/zen/images/categories/DMS-40mm-AE92.jpg

I hope this isn't off topic but with all of the talk about suspension and me being a noob to high performance parts I want to ask a question:

I recently purchased a 335 coupe and am finding that I would like less body roll and higher performance suspension. I am starting to drive a little harder and am going to take some performance driving courses along with some track days.

I would like a little drop; about an inch. I would love to retain the excellent daily driver ride quality also.

Does anyone know of a suspension kit and installer in the Northern California area that could do this?

Thanks

2006 Feb RCE nice article on springs. Read and learn everyone, knowledge is power :)