Been a lurker on this forum for some time, and have been a long-term car nut/mechanic (engineer by education) who enjoys cars and tweaking them to my taste. Have an 07 Accord Special Edition that I’ve owned since new, installed the Acura TL Type S rear sway bar at ~8k miles, but at ~60k miles I decided to move the suspension up a notch. My goal was to retain most of the OE ride comfort, and to reduce the roll and grip in turns. Researched this forum at length and couldn’t find much directly applicable information; most was about people’s effort to significantly lower the car. Yes, lowering the CG is a step toward my goal, but done too much significantly degrades the ride comfort.

After review of products available, I chose to go with H&R OE Sport Springs damped with Koni Sport Adjustable Struts. The H&R OE Sport Springs are progressive wound and are supposed to lower the car about 3/4" front and 1/2" rear; when combined with the Koni’s (using the clip position that closely matches the OE struts) actually yielded drops of about 1” front and 1/4" rear. Handling on the car was great, much better weight distribution and grip between inside and outside tires in a turn, and very near neutral balance front-rear. However, the ride was too rough on bumps for my liking. Turns out, the OE struts do very little damping on compression and almost all their damping on extension. The Koni’s have significant damping on compression (hence the rough response to bumps) and only adjust damping for extension; I found the best ride comfort with the Koni rebound set 1/4 to 1/2 turn from the stiffest position. After driving this way for a little over 4k miles, I decided the ride was too rough for a “family car”. I concluded the Koni’s compression damping was my biggest problem, not the H&R springs, so I decided to go back to the stock struts with the H&R’s and hope the stock struts could handle the higher spring rates without blowing.

With the H&R OE Sport Springs mounted on the stock struts, the resultant lowering from the factory setup turned out to be closer to 1" front and just under 1/2" rear. Since the H&R’s are progressively wound, the ride is very near stock comfort for most conditions, and only slightly rougher on significant bumps. Handling in corners is still vastly improved over the factory setup; however, the stock struts do make the ride feel a bit more “floaty” when compared to the Koni’s. For me, the ideal would be a little less compression damping than the Koni’s, but with their very nice extension damping. Oh well, everything is a trade-off. Now I need to sell the Koni’s and hope the OE struts last (I think they will).

One other thing I learned from this effort is that ANY lowering on the rear will push the rear camber too far negative. With the 1/2" drop in the rear, my worst wheel (right) went to -1.9 degrees, which isn’t a whole lot, but over ~4k miles like this there was clearly additional wear on the inside of the rear tires (worse on right). Because of this, when I changed back to the stock struts, I installed a set of Wicked Tuning adjustable upper control arms to allow rear camber adjustment. Chose these as opposed to the adjustable lower links because of the geometry of the rear multi-link suspension; changes to the upper link will have less impact on toe than changes on the lower link. I’m going to have the rear camber set to around -1.2 to -1.3 degrees, my guess at optimum.

Conclusion: The H&R OE Sport Springs are a fantastic handling modification with minimal impact on ride comfort, and I believe they can be used with OE struts. If you want to seriously lower the car, change the struts too; remember, the Koni’s also have lowering slots for the spring perch). With ANY lowering of the rear, plan to provide rear camber adjustability. Good luck.

 

Nice write up on your upgrades, thanks for posting.

Did or have you found a set of tires that seem to work better?

 

Thank you poorman212.

Currently have about 35k miles on my Yokohama ENVigor's (made in Japan), and have liked them very much; probably have 5k-10k left on them. The US made equivalent, Yokohama 580 (which I have put on 2 other cars), are not as good (grippy). One problem, though, with the ENVigor's is they are directional tread and can only be rotated front-back on the same side and not X'ed to the drive wheels as I like to do for more even wear.

 

lots of good info. I am putting tein street advance coilovers on my 05 accord. Cant wait,i want it to handle better. I have the yokohama envigors on my car, i had dunlop sport signatures before them and they were way better. The yokohamas dont handle as well or grip as much and the sidewalls give on turns compared to the dunlops. If you want a tire for performance I would go with Dunlop but for comfort the yokohamas are quieter and absorb bumps way better.