socalwrench

ALL the REPUTABLE SPRING RATES and LOWERING HEIGHTS are on this thread. This way I, and many others, can make an informed decision. It is my understanding that the FR500 springs use a modified design and wouldn't apply to the typical street car- such as a full coilover setup. This thread excludes full bodied coilovers.

Thanks to SteedaGus and F1Fan (Chip) for helping complete this information.

As of September 2009:
Name- (part number)- lowering amount- spring rates

Stock/Factory GT springs (Tags= Yellow, Orange) - front: 136lb/in / rear: 142lb/in

Eibach Pro-kit (pn 35101.140) / Ford Racing (K-springs) (pn M-5300-K) 1.5/1.7 - both variable front: 173-248lb/in / rear: 195-236lb/in

Eibach Sportline (pn 4.10135) 1.6/2.0 - UNKNOWN (*tested by Chip- reportedly very high)

Steeda Ultra-lite (pn 555-8206) 1.25/1.5 front: 195lb/in / rear: 175lb/in

Steeda Sport (pn 555-8216) 1.0/1.25 - front: 200lb/in / rear: 175lb/in

Steeda Competition (pn 555-8241) 1.0/1.25 - front: 225lb/in / rear: 185lb/in

H&R Sport (pn 51655) 1.0/.75 - UNKNOWN

H&R Super Sport (pn 51655-77) 1.7/1.9 - both variable (working rates) front: ~250lb/in / rear: ~200lb/in

H&R Race (pn 51655-88) 1.5/1.4 - both variable (working rates) front: ~300lb/in / rear: ~275lb/in

Roush Performance {sold in pairs} (pn 401294 and 401295) 1.0/1.0 - UNKNOWN

Roush Extreme (pn 402331) 1.0/1.25 - UNKNOWN

Tein H-tech (pn SKG12-BUB00) 0.94/1.65 - front: 163lb/in / rear: 163lb/in

Tein S-tech (pn SKG12-AUB00) 1.5/2.24 - front: 174lb/in / rear: 174lb/in

Vogtland (pn 950084) 1.3/1.3 - variable front: 160-240lb/in / variable rear: 120-220lb/in

Saleen/Racecraft (pn 10-1302-B12999) 1.25/1.25 - UNKNOWN

Sprint (pn 2115) 1.6/1.5 - UNKNOWN

BMR Fabrication Inc. (pn SP009) 1.25/1.5 - variable front: 120-165lb/in / linear rear: 140lb/in

*NOMINATED STICKY*

CHECK OUT PAGE 4 - post #33 - FOR MORE ACTUAL TEST DATA

socalwrench

I've gathered the amount of lowering, but need help filling in the spring rates.

Texotic

i don't know any of the rates... maybe, since Sam sells a lot of those springs, he may be able to chime in with info? I would be shocked if he didn't have that stuff on file somewhere.

socalwrench

I don't know who Sam is, but anything he can add would be great.

SteedaGus

Steeda Ultra-lite (pn 555-8206) 1.25/1.5 (exact unknown- APPROX. front: 195in/lb rear: 175in/lb)

Steeda Competition (pn 555-8241) 1.0/1.25 225in/lb front, 185in/lb rear

socalwrench

Thanks for the additional information, it has been entered.

thedrod

good initiative socalwrench....this would be very useful info.

jahudso2

Anyone know what the stock spring rates are?

Doogie65

Here's a thread on TMS that has some info about the Bullitt springs...

http://forums.bradbarnett.net/showthread.php?t=470588

Rubrignitz

I could have sworn I heard 175f/150r stock but don't quote me on that. Feels about right to me after running Steeda sports and then comps.

H&R Races must be in the 250/200 f/r range. Those springs were so low and so tight!