Are the Eibach prokit springs progressive (these: http://www.rx7store.net/product.asp?0=219&1=280&3=483)?

After searching, this thread says that they are (https://www.rx7club.com/showthread.p...ghlight=eibach) and this thread says that they are not (https://www.rx7club.com/showthread.p...ghlight=eibach). Thanks .

-Matt

 

matt,

the eibach Pro Kit springset is not progressive.

i have personally rated them over a 4 inch stroke. the rate is 350 fr and 255 rear, up 33% from stock. the Eibach part 5525.001.

they are really nice springs and work v well w the stock shocks. i don't recommend progressive springs as they change rate in a corner.

howard coleman

 

Hey Howard,

I have the Pro Kit springs and was also under the impression they were progressive. I thought the Pettit Eibach Track Pro were different and were their linear product.

Are they the same product, same type of spring but different spring rates, or just not the same at all?

 

Thanks for clearing that up. I'm going with eibachs and koni yellows, would the Pro Kit be too harsh for a daily driver (no track events)?

by up 33% from stock do you mean that these are 33% "stiffer" than stock? Is that a fair way to interpret your statement?

EDIT: it looks like me and Mahjik responded at the same time... I guess it's still up for debate .

 

i will check w eibach tomorrow and settle any confusion.

the springs i recommend do have the 5525.001 eibach part number and are not progressive.

as to 33%, yes, that is to say their rate is 33% higher than the stock springs and they are a dream to drive on the street as well as track. you wil not find them to stiff.

do make sure you are not running too much tire air pressure.... 30 max cold in front and 27 in the rear. too much air pressure makes for a buckboard ride.

howard coleman

 

Thanks Howard. It will be nice to put an end to the "Eibach" confusion once and for all.

 

...

 

27psi? thats a little low. tire is going to wear on the outsides a little more.

 

Howard has many years of SCCA racing under his belt, he does know a thing or two...

27 psi is the COLD temp, that should raise to 32-33 hot temps (or more). I'll agree though that the pressure sounds pretty low and I really like how the car feels with 32 psi COLD temps. It may be slower than with the tires at 27 psi COLD though.

 

as matt discovered there are many opinions re Eibach springs on the forum... some relate to ride qualities, which are subjective, but other opinions relate to whether the springs are progressive or linear as to rate.

the theory on progressive rated springs is having it all... soft initially for potholes and stiffer on greater compression for the track.

the major drawback w progressive springs is that as the car leans in a corner the spring rate changes. it is hard enough to drive on the limit of adhesion without the springs changing rate. i don't like progressive springs.

'just run the right linear rate and you'll be a happy driver.

as promised yesterday, i called Eibach and spoke w Tyson Cutrer. Tyson is a head of the tech dep that Eibach maintains in the U S.

Tyson said that the springs are linear. the part number is 5525.140 for the four springs. 5525.001 is for the front spring (Eibach lists them at 365 lbs/inch) and 5525.002 is the rear listed at 275 pounds per inch. ( I had them at 350 and and 255). Eibach does not offer progressive rated springs for the fd.

Tyson said that they were designed to work well ( read not be overpowered by) the oem shocks. i have previously made the point that they work very well w the stock mazda shocks.

Eibach also offers a front sway bar for the fd. part number 5525.3205 and a bar bushing kit at 5525.320hk. it fits in the stock location and uses the excellent mazda end links... i believe it is 33 mm.

so that is the deal re Eibach springs... they are available from lots of vendors and i see them pop up in the classifieds on our forum. i have no connection w Eibach and am just sharing my conclusions in order to be of some help. i run Tein coil-overs but the transformation of the fd with Eibach springs and stock shocks should not be underestimated.

i know two people w fairly well modded fd's that have both told me that the Eibach springs are their favorite modification.

howard coleman

 

Thank you so much Howard (someone sticky or save this thread).

Obsolutely!

 

Thanks Howard!

 

I run the Eibachs with Koni sport adjustables (aka yellows). This combo rocks!

The part number on the springs are indeed 5525.001 and 5525.002 as howard mentioned.