Here are some springs I did research on and also contacted several companies to get information on the drop and spring ratings... Please add any other lowering springs spec/information thats not listed, and I will add it on the list :thumb:
Company //// Ride Height F/R //// Spring Rate F/R :: (L) Linear (P) Progressive
Part Number----4H913
Company //// Ride Height F/R //// Spring Rate F/R :: (L) Linear (P) Progressive
- Stock '06 Si Coupe //// 0" / 0" //// (L) 200 lbs. / 230 lbs.
- Eibach ProKit//// 1.0" / 1.2” //// Coupe (P) 137-222 in. lbs / 143-262 in. lbs
- Eibach ProKit//// 1.2" / 1.0” //// Sedan (P) 137-222 in. lbs / 142-262 in. lbs

- Eibach Sportlines //// 1.4" / 1.4” //// (P) 125-222 in. lbs / 131-262 in. lbs

- Skunk 2 //// 1.5” / 1.4” //// (P) 135-184 in. lbs / 125-273 in. lbs

- Tein H-Tech //// 0.79” / 0.67” //// (P) 220 in. lbs / 250 in. lbs

- Tein S-Tech //// 1.54” / 1.42” //// (P) 230 in. lbs / 270 in. lbs

- Tanabe Sustec GF210 //// 1.0” / 0.75” //// (L) 187 in. lbs / 225 in. lbs ; +20-30% est.

- Progress Group //// 1.3” / 1.2” //// (L) 240 in. lbs / 330 in. lbs

- Neuspeed Sport //// 1.6” / 1.6” //// (P)+-218 in. lbs / +-448 in. lbs

- Neuspeed Race//// 2.0” / 2.0” //// (P)+-303in. lbs / +-460 in. lbs

- H&R Sport //// 1.5” / 1.3” //// (P) N/A in. lbs / N/A in. lbs

- Comptech Sport //// 1.0” / 1.2” //// (P) N/A in. lbs / N/A in. lbs
- HFP Springs //// 1.0” / 1.0” //// (P) N/A in. lbs / N/A in. lbs

- B+G Sport //// 1.6” / 1.6” //// (P) 25%+ in. lbs / 25%+ in. lbs

- Swift Springs USA
Swift Sport Springs
CIVIC SI--2 Door-FG2--Front 2.3-4.0kg/mm--129-224lbs/in--Drop 30mm/ 1.2in----Rear 3.2-4.6kg/mm--179-258lbs/in--Drop 20mm/ 0.8in
CIVIC SI--4 Door-FA5--Front 2.3-4.0kg/mm--129-224lbs/in--Drop 30mm/ 1.2in----Rear 3.2-4.6kg/mm--179-258lbs/in--Drop 25mm/ 1.0in
CIVIC-----2 Door-FG1--Front 2.3-4.0kg/mm--129-224lbs/in--Drop 25mm/ 1.0in----Rear 3.2-4.6kg/mm--179-258lbs/in--Drop 15mm/ 0.6in
CIVIC-----4 Door-FA1--Front 2.3-4.0kg/mm--129-224lbs/in--Drop 25mm/ 1.0in----Rear 3.2-4.6kg/mm--179-258lbs/in--Drop 20mm/ 0.8in
Part Number----4H913
