Maximum Motorsports billed the Koni's at 40lbs, while Ford Racing Parts list a M-5300-P spring kit at 33lbs (for estimate), so I'm guessing about 75lbs total. UPS shows the shipping via Ground (3-day transit) to be $78.64.

 

Thanks for your input. I think the stock brembo setup lacks a decent rebound so I hope the rebound is improved with the koni's. I haven't found anyone without a lowered setup using str.t koni's

 

Based on Koni's site where they chart rebound and from what I've read the str.t 's seem to be the yellows at 1/4 turn. They also are valved better for street driving. So in other words the yellows at 1/4 turn (or full soft, whichever is most like the strt) they will still be rougher than the strts.

I get the advantages of adjustable. However what some seem to forget is that with adjustability, even on soft, still comes with harshness since they are tuned for race apps. I also don't want to screw around finding the "sweet spot" as the OP found is a pain in a A$$.

Only issue is going with new shocks kinda negates most of the brembo 55d kit advantage. The design is to work with the existing shocks valving and suspension but be lower. If you change the shocks than should you also have a stronger spring rate? Also you then need an alignment etc.

 

The strt is designed as a stock replacement that can be used in lowered applications. I think that the ride and handling issues if the mustang have more to do with shocks than spring rates. I think the strt would be a good way to fix the bouncing and brake dive that our cars have. I would rather change both myself and did. The steeda sports mild drop fixed my issues with the cars handling. I do agree that the strt with a springs would be enough for most folks, including myself. I probably overspent. I was sold on the sports based on vendors mention of better build quality of the sports and better durability.

 

The 55d kit setup did lower 1/2 inch and only slightly improved the bounce on my brembo car. No need to realign. Also maybe an improvement to cornering. I'm sure a lowering setup would be better but I did not want that. The str.t (orange) are suppose to be good for a oem setup and many say they work for a lowered setup. Guess I will find out as I'm close to biting the bullet.

 

So you are unhappy with the 55D alone?

I am increasingly more confident with the decision to go with 55D rears only as opposed to the steeda sports. Everyone knows the sports are amazing. But I'd rather keep the front where it is and not ramp up spring rates.

Question now is do I also add koni strts at the same time. That's where you can help Dusman.

 

I would take one step at a time. The 55D springs were worth it and an easy install. I have had them for over a year. Still on some(only on some) road conditions the typical ride on the Brembo stangs exhibit a type of bounce. I'm suspected this caused by the shocks and struts being typical cost cutting by the manufacturer. I will be going soon to try the Koni str.t. I like the ride height and hope to make things a little better.

 

Are you talking that oscillation that occurs when your on the highway and hitting concrete expansion joints? That has more to do with the car's wheelbase than the shock/strut & spring combo. Despite having done 3 different suspension setups on 2 GTs and 1 GT500 it still occurs.