If you are going to lower a car 3+" which most coilovers can, you need a high springrate to keep the tires out of the fenders.
I took the 3" as a arbitrary number… nobody should be lowering 3 inches, go to airbags at that point. not to mention roll center problems etc when you are that low.
alpha, this is all first hand experience from like 9 years of playing with suspensions. I started with my maxima on AGX + GCs and then went on to play with strut relocation to get more travel etc, and most recently had custom valved and sprung buddy club racing specs on my evo along with roll center kits etc. I’m about to install a low end coilover setup into my bmw for a nice look and street ride.
It all comes down to the right tool for the job… and the putting a short spring on a full length strut is never the right way to go, period.
lol this is making me laugh, im not trying to be an ass, but airbags are a joke and are not meant for performance in any way, and although a car should not be “slammed” it would hardly effect “roll center” the negative aspects would be reduced shock/suspension travel which would need HIGHER spring rates to keep the car from bottoming out
when I put a roll center kit on my evo I noticed a big difference… It cornered so much flatter which gave the car a greater contact patch which in turn means more traction so I can hold more speed in a given turn… I wouldn’t under-rate the importance of suspension geometry.
low and stiff are not the only things that matter.
From my experience at the shop doing suspensions, there are a few factors you have to look at.
The quality of the OEM strut is big. Your TL probably has good struts from the factory, probably made by KYB. The fact they have 60k miles on them isn’t great but, if they aren’t blown you could definitely use them with lowering springs.
The quality of the lowering spring is also huge. There are many name brand lowering springs that I would never use. Overall quality and R&D goes a long way with springs. Get something that is matched to your OEM struts.
Ride height is key. Don’t get something that is going to destroy your suspension geometry. This goes for people with coil-overs also. If you want to slam your car look at things like roll center and bump steer correction kits. On my EP3 Civic, I used a roll center correction kit with Buddyclub racing spec coil overs and it was awesome. Like theblue said, it really flattens out the car in the corners and makes it handle way better.
I went through the same thing your going through with my Evo X. I have had cars with both lowering springs and full coil overs. I decided to go with a good quality lowering spring (Eibach pro-kit) and OEM struts which are made by KYB. Coil overs are nice but, in less you get something that is very expensive (moton, Ohlins, KW) your not gonna have good ride quality on the street.
Hope this helps.
see if you can find a used a spec suspension, a little firmer and plus lowers the car a bit. Remember a spec packages were 18" wheels too
Okay I need to know because it came up in this thread too, whats the real reason behind stock struts blowing out, is it the low stock rates, or is it the dumb people who leave off the bump stops or (dump it 2.5") and then blame the shocks and they get a bad rap
I know the stock rates are not optimal and alot of us prefer the stiffer susp
If you want to run lowering springs, Check out Vogtland, they have some decent spring rates, and atleast for my car, they are not progressive rates- that said I havent driven them yet
Any good coilover is generally a matched set. No “good” coilover system costs 1k like mentioned. If you are looking for a good look and decent ride then the Tein CS comfort series might be what you are looking for. They match the valving and stroke of the piston for the specified height so that it does not over work the fluid. When you over stroke the shock and heat the fluid it aerates and won’t dampen properly. For a coil over system that’s about all I would purchase for street use no need to spend multi thousands of dollars for anything that is not a race car. A good matched spring and shock combo would do you well also. With Koni Yellows you can place the spring perches on the shock in places that will lower the spring but not compress the spring and thus stiffening it. So that you still retain the proper spring rate but a lowered ride height.
Stock shocks are designed to cycle at a certain rate, meaning go up and down at a certain amount each second. If you lower a car using lowering springs and stock struts you are making that cycle rate higher, so that piston is not making smaller movements up and down due to the limited range of motion but it is also making faster transitions. Shocks fail when the oil over heats, aerates and can no longer help dampen. This is a general reason, there are other reasons that attribute to failure but you get the idea.
okay thanks for the info Carnut
I want to add some info for Micah about the Vogtland springs. I didn’t want to drop my car more than 1.5" like Micah, but I wanted to get stiff spring rates but still go lowering spring route for my firebird.
The stock spring rates for my car, from memory, is something like
250 lbs/in front, 100 lbs/in rear (non progressive)
Vogtland rates 1.2" drop (From Vogtland sales rep) (180 shipped new on ebay)
540 lbs/in front, 180-230 lbs/in rear (non progressive)
Non progressive will have firmer ride, but should help with transitions
SLP (Fbod tuner) & Eibach sport lines (~$220)
~250-480 lbs/in front, 100-170 lbs/in rear (progressive rates)
My past experience has been with my 240sx on Eibach Sportlines and Koni Single Adjustables, and the performance and ride was great.
Even SCC only got their S13 project to .96 g’s on JIC coilovers before adding Whiteline sway bars, and they had to change to lower spring rates to increase grip. You also need compliant suspension for safety and speed in the real world over bumps
It seems coilovers have great adjustability, but without well-informed proper setup, they dont always provide great performance, even though they have a higher potential
Everyone says lowering springs will kill stock shocks, but I used my stock 98 cobra shocks for 2 1/2 years with eibach sportlines(2in drop, harsh springs) and I just took the shocks off and they aren’t leaking at all and have normal comp. and rebound.
The car rides like shit, and still does after the bilstein HD’s, but what a difference, they are much better suited for my springs, so much tighter.
I’m sure the fact that I don’t drive it in the winter helps but I’m just saying you can lower a car with stock shocks just fine. For the work, since I’m sure you have coilover struts at all four corners, I would replace the struts when doing the springs. Keep in mind, many aftermarket struts like tociko blues are no better than stock so I don’t know why people say you NEED to upgrade and then use something that’s the same caliber as stock. But since your doing the work of changing the strut anyways to do the springs, I would say just do the struts now, you’ll have to change them at some point anyway.
But if you want a drop that rides as good as stock, get coilovers.
I picked up FK coilovers for my E36 for $399. they are GREAT. the big trade off is that the only adjustment is height on the front.
the spring rate + valving is PERFECT - I never expected to be so happy with such a cheap setup.
the irony is that my track car is a E30 with ireland engineering springs and soon to be installed bilstein sport struts. perhaps not the way I would have gone it if I hadn’t already started with the springs and happen to really like the rates.
Great info. here is this thread, very cool stuff.
For what it’s worth Micah I’ve been running the eibach pro kit on my car with stock struts, about 1.25" drop. The ride is a little “stiffer” but I wouldn’t say any more rough.