How "progressive" are you?

[914 Dave]

For a time I had some "progressive" rate springs in the back of the 914, and have since been messing around with different # ratings of straight rate springs. Of those who would know, for auto cross events, not road racing, not the trip to the auto cross, whadda think? Straight rate or progressive? I like my straight rates, and will put up with the stiffer ride quallity to and from the events, but was just wondering what others thought...

[weidnerpaul]

For a time I had some "progressive" rate springs in the back of the 914, and have since been messing around with different # ratings of straight rate springs. Of those who would know, for auto cross events, not road racing, not the trip to the auto cross, whadda think? Straight rate or progressive? I like my straight rates, and will put up with the stiffer ride quallity to and from the events, but was just wondering what others thought...

Someone posted on a thread here that the progressive aren't consistent in their progression in compression/expansion & that they wouldn't be good for AX, I forget the thread & person but you might find something in a search.

Paul

AKA "A Miata owner in waiting"

[GodSquadMandrake]

I have progressive's. They transition funny and I would prefer a straight rate spring.

[MNbiker]

Dave,

Progressive-rate springs are generally considered a good thing for street cars, as they provide a more compliant ride for typical use, but still keep you off the bump stops for the heavier hits. However, for a competition vehicle, straight-rate springs are generally preferable, as they provide more predictable response.

[MattD]

What kind of springs do stock street cars have? Or does it vary?

[the tick]

For a time I had some "progressive" rate springs in the back of the 914, and have since been messing around with different # ratings of straight rate springs. Of those who would know, for auto cross events, not road racing, not the trip to the auto cross, whadda think? Straight rate or progressive? I like my straight rates, and will put up with the stiffer ride quallity to and from the events, but was just wondering what others thought...

Progressive springs are a compromise between reasonable ride quality (street stuff), and still keeping you off the stops. When they are used in a "race" vehicle you lose out on the initial suspension control (i.e. the start too soft and use up a lot of hte travel initially) and don't get stiffer until the soft portion coil binds.

If it's a fun only car, go straight rate and deal with the rough ride to and from. (my $.02)

[MNbiker]

What kind of springs do stock street cars have? Or does it vary?
Most of the stock springs I've seen lately were wound with a progressive rate. It's pretty easy to tell the difference, as progressive-rate springs typically have noticeable a variation in the diameter or distance between coils, whereas standard springs appear uniform for the entire length of the spring.

-Steve

[73GT]

Dave
Linear are best as progressive can upset the suspension when they start to frim up when your driving on the edge thru chicanes and slaloms (fast transitions). But the linear are too firm for normal daily driving.
I like linear springs for laping events (road racing) also.

73GT

[phile]

For a time I had some "progressive" rate springs in the back of the 914, and have since been messing around with different # ratings of straight rate springs. Of those who would know, for auto cross events, not road racing, not the trip to the auto cross, whadda think? Straight rate or progressive? I like my straight rates, and will put up with the stiffer ride quallity to and from the events, but was just wondering what others thought...
Progessive or "rising-rate" springs are very good for trucks, and streeters you use like trucks. They ride nice when the are empty and can carry the weight when you put lots of stuff inside. I had Moog Cargo-Coil springs all around in my K-cars. They showed their worth when I put heavy tools in the cars. With a set of R-compounds on the autocross course they were OK, but springs which gave firm control right away would have been better.

[SUV-ETR]

for a competition vehicle, straight-rate springs are generally preferable, as they provide more predictable response.

Ditto.

However, it is worth noting that there is a 3rd possibiltiy: multi-rate springs. This is where you combine several different straight-rate springs on one corner. Many touring cars use this approach, especially in the BTCC, and they combine it with really goofy hocus-pocus digressive valving on the shocks so that it ends up working backwards from how you might think: It is mega-stiff for the first inch or so of travel (touring cars tend to have strut suspensions, which often means that near-zero suspension movement is a good thing) but if they hit a huge bump or a curb, the suspension will suddenly become compliant to absorb the bump (touring cars tend to bang pretty hard on the curbing at most tracks).

I'm not actually recommending it for you, especially since I still don't understand myself how that works, but interesting trivia I read somewhere...

Neal