1985-88 Fieros use the same springs. 1984's use some of the same rear springs (all but one) as the 85-88's but different front springs.
REAR SPRINGS: (EXC WS6) CODE (W/WS6) CODE ------------------------------- 1984 10029092 NWY (Stiffest) 10029091 NWX | 10029090 NWW (Softest) 1985-88 10030180 NXD 10034976 NYM (Stiffest) 10029092 NWY 10034975 NYL | 10029091 NWX 10034974 NYK | 10029090 NWW 10034973 NYJ (Softest) FRONT SPRINGS: (EXC WS6) CODE (W/WS6) CODE ------------------------------- 1984 10029670 DMF 10029675 DMN (Stiffest) 10029669 DMD 10029674 DMM | 10029668 DMC 10029673 DMK | 10029667 DMB 10029672 DMJ | 10029666 DMA 10029671 DMH (Softest) 1985-88 10034097 FJA 10034102 FJH (Stiffest) 10034096 FHZ 10034101 FJF | 10034095 FHY 10034100 FJD | 10034094 FHX 10034099 FJC | 10034093 FHW 10034098 FJB (Softest)
The codes can be found on a paper tag on the spring or on the Service Parts Identification Label on the left front inner fender. The spring codes for my 85 GT from the label are; 6JH, 7JH, 8YM and 9YM (JH = FJH, YM = NYM)
6 code = left front spring code
7 code = right front spring code
8 code = left rear spring code
9 code = right rear spring code
From: Scott Backer
Here is another bit of information for your collection.
1988 Formula WS6 (sequence number 222054)
Information from tags on springs
Front 10068654 ARD
Rear 10053694 PUC
Information on parts sticker
6RD 7RD 8UC 9UC
From: Bill Fuhrmann