You should post who the company was that you got your springs from. If you were happy as you mention, then promote their service and products. Its what forums like these are for!
Negative comments and reviews on any forum seemingly any topic even none automotive on www out balance people that are satisfied. Humans just like to bit*ch more than praise.
I also prefer linear spring for handling over progressive. The main reason is handling predictability... but most applications using a correct none OEM linear springs to improve the overall handling increase comes at the expense of ride comfort.
Your MAZDA looks good, and your resolve seems to have satisfied you.
Pre ASE proofread none edited version excerpts
.......After contacting several of the most common and a few independent less known spring companies and very few were willing to give me the spring specification or even lb rating of the springs offered. ...................
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why this information is not supplied or researchable on their web sites or with contacting them.
......................... The After market and chasses Suspension manufacture have NO standard for height measurement or where the measurements are taken on the vehicles. This means as an example that one brand may use the lower wheel well skirt and another may use the lower bumper to get there installed heights.
............. The Spring production supplies for a specific kit may change, supplied spring specifications change with a different rate spring within the same kit number. This means that the same kit # offered a few years ago may have different rated springs then the one currently offered with that same kit #
.......................... Really Vague definitions of specific application ranges of end user for ride height.
I found that most manufactures seem unwilling almost defensive by nature to even give performance specification other then generalized advertised information or even an approximate percentage spring rate increase over stock oem springs. But apparently after a insistent line of questioning the spring rates supplied from most manufactures range from 10% 25% increase over stock OEM springs.
Almost all used quality material and manufacture process to produce the springs So the price variance was surprising considering this?
Retail kit average price range was from 139.00 to 325.00
My conclusion is that no one Spring Supply Company has the advantage over another.
If I had to suggest a spring company I would see what other’s have used based on like modifications to your own PT to achieve the same results.
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.............................................The spring constant (stiffness) of a coil spring equals:
k = compression / force = D^4 * G / (64*N*R^3)
where D is the wire diameter, G an elastic material property, N the number of coils in the spring, and R the radius of the spring.
................................So increasing the number of coils decreases the stiffness of the spring. Thus, a progressive spring is progressive because the two parts are compressed equally until the tightly wound part locks up, effectively shortening the spring and reducing its compliance.
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...............................For normal driving, the vehicle uses the upper 3 or 4 'tight' winds to absorb small bumps in the road. For more spirited driving, like cornering , the coil springs are being compressed more, they resist more. The effect helps reduce the suspension travel at the top end resulting in less body roll, and better road-holding. The fact that the springs are progressively wound is what accounts for the lowering factor. The springs are not made shorter just wound differently. .....
Most better known aftermarket springs are generally made from higher grade material than factory specifications.
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