What spring rates for coil overs?

[jasonpaulbauer]

Im planning on making DIY coilovers for the festi. I have pretty much everything I need except the springs.

Its a DD, but has Aspire brakes and sway bar. Plus has 14" wheels with 185/60 tires.

I know for the rear I need stiffer than stock as it really sags with any humps in the road or with passengers.

Right now Im considering 225lb/in front and 150lb/in rears.

What spring rate did you use?

[Pu241]

Jasonpaulbauer,

Check this search out:

http://www.fordfestiva.com/forums/search.php?searchid=47211

I know Skeeters Keeper and Quadawg have some good info and even though Gomez sold his setup, there is useful info in his [FS]thread too!

OK, apparently I can not link to a search result
So, use the search function and the terms "spring" "rates" and you see what I'm talking about.
FYI, if you use "rate" you get different results.

[skeeters_keeper]

150lb front/125lb rear... 25% increase in spring rate over stock (stock is 110/90), assuming you use GR2's they have 15% increase in damping over stock, so their fairly closely matched to the 150/125 springs... much heavier than 150/125 and I think they will feel under damped. I love the 150/125 rate for a DD, its nice a firm but not bouncy. a million times better than stock.

[festurbo]

150lb front/125lb rear... 25% increase in spring rate over stock (stock is 110/90), assuming you use GR2's they have 15% increase in damping over stock, so their fairly closely matched to the 150/125 springs... much heavier than 150/125 and I think they will feel under damped. I love the 150/125 rate for a DD, its nice a firm but not bouncy. a million times better than stock.

Nate. Will this spring rates work good on a Festiva with the B6T setup? I'd like to be able to use it as a DD and considering that the B6t and G25M-R setup is heavier than stock,should I use stiffer front springs? Also,I will be using adjustable dampening shocks and lightweight wheels. My reason for going with coilovers is the tires that I chose to use. I have a set of 15" wheels with 195/50/15 tires(29lbs. for each wheel and tire). I do not care too much about lowering the car as long as it does not rub on the fenders and quarter panels. Almost forgot that the battery is relocated to the back and also allow around 80lbs. for the music system(like I said,it is a DD).
Anyone else have any suggestions? Thanks.

[skeeters_keeper]

If you still want it to be a relatively comfortable DD, then yes. For at the track, stiffer would be better... as long as you've got better shocks than the festiva GR2's. What shocks are you planing on using?

I would also suggest going with a shorter spring (8" or so, instead of the 10" i used). Your wheel/tire combo is a little wider than mine and you will need all the clearance you can get, plus it will give you more of lowering options. if you decide to go for the somewhat cheaper 10" springs it will still be fine, but you'll probobly need about 1/8" of lift over stock in order to get max clearance in the rear.


What wheels are you running? my miata wheels with 185/60/14 weigh about 32lbs each.

[festurbo]

Nate. I have Konig Helium 15"x6.5". The shocks are Tokico Illuminas 5 way adjustable. I would like to have a ride like the EVOs and STIs factory ride. I do not think this is impossible as long as the shock can handle the springs. This cars ride firm but is still tolerable for DD. I have FMS springs and they are O.K. for a factory or B6 swap festiva but I think they are too soft for a more powerful setup.

[skeeters_keeper]

What car are they from? (just wondering if this will be a good alternative to the KYB AGX)


For your purpose I would suggest going stiffer... 200/150 will probobly be good. One of the best things about coilovers, if you decide you don't like the rates up front, for $40 or so a spring you can replace them.
From what I understand, FMS springs are only 15% stiffer than stock... I've not been impressed with them from what I've seen, though I've never had them on my car.

[m715]

The problem with the FMS springs are that they require more dampning than the GR2 can handle. My experience is that the KYB supers BARELY get the job done, and the Bilsteins were just about right. Problem is, of course, both are now obsolete. I am going to have to try the coilover too, and am very interested where the optimum ends up spring/dampner wise.
I am like you too, Nate. I like the ground clearance too, or at least the option to adjust as needed.

Michael