thank you a lot guys!!
GeorgeH we are gonna discuss about your kw when you are gonna sell it!!!

..just my 2c of experience w/coilovers and street ride quality, the OP's question. 1st, let's take it as a given that ANY coilovers will hurt street ride no matter what, no matter what settings used ... basically because the springs are stiffer and the ride height is generally lower than stock.

So .... what ELSE can be done to help improve the ride with coilovers? The answer is simple - provide more ride compliance on the street to compensate. How? Use more compliant tires. Aside from considering the tire brand/construction itself (very difficult to do) there are two ways.

1. increase the tire sidewall height.
2. use a wider cross section tire than standard for the the wheel.

For #1 - with stock wheels/tires (18') that's difficult without increasing the overall tire diameter too much. But with smaller wheels (17") you take advantage of an automatic 1/2" greater sidewall height while still keeping the same overall tire diameter. 1/2" may not seem like much, but I've found it makes a HUGE improvement in ride quality with coilovers on the car.

For #2 - increasing the section width on the same width wheel will offer less sidewall support, softening the ride.

Method #1 provides the most benefit, but even without combined these methods you can arrive at a point of equal or better ride quality with coilovers compared to stock without coilovers. I'll invite anyone to come for a ride with me to see the result and compare.

So, if I follow your logic, adding coilovers on a car already running runflat with their stiffer than normal sidewalls would be a poor combination. Is that correct?

I just dont see why people who want to pay some serious money for coilovers are worried so much about street ride quality. If your going to be paying a few grand for a set of coilovers, you should want the best performance you can get, not the best street ride quality..

...on the other hand, the art of good valving is to give good performance without too much sacrifice in ride quality, at least for a dual-purpose setup. Ohlins are well known for this attribute.

But yes, there will be some inevitable ride degradation, unless you are a stock class autocrosser who is used to driving around with Konis on full stiff all the time. But, if I were to compare the ride degradation of my '94 Miata on JICs to my '04 RX-8 on KWs, the KWs pulled of a magic trick, as far as I'm concerned. Of course, I had very hard springs on the Miata so it's not a 100% fair comparison, but valving does play a big role in ride quality.

Of course, if you are looking to build a street legal car who's primary goal is to be competitive in some sanctioned race series, then ride quality falls down in the list of priorities.

Sounds reasonable, but I've never had runflats - but the consensus seems to be they are harsher riding than normal non-runflats.

Personally, with coilovers on the street I use 245/40R18s on stock rims and they are more than comfortable. I usually run lower than stock tire pressure like 28psi. I also have some 255/40/R17s on 17"x9" wheels and they are also fine on the street with 30-32psi. If I ever went to say 255/45R17 on a 8.5" rim (to get back to stock diameter and a smaller width wheel) I think it would be really Lexus cushy!

As far as why have coilovers at all for the street, the reason must be to lower and get some handling improvement. But I whole-heartely agree, getting back to a good ride is very important, because unless you have a trailer queen for track use only, you still have to drive even a track worthy car on everyday shitty roads.

The reason I had been considering coilovers is for the adjustability of ride-height. With even two adult passengers, I can't clear the speed bumps in the condo complex where I live and I'm quite tired of having to repair the undercoating over and over. An additional 15 to 30mm of ride height in the rear would be very helpful for me. If it happens that coilovers don't have a wide enough adjustment range to allow for that possibility, then they have no value for me.

^It seems like your more interested in ride height than shock performance, therefore you should not be looking at stuff like Bilstein, Ohlines, KW...etc. As you will not use them to their full potential.

One of the options I've been looking at are the rear OE Bilstein shocks from the 2009+ model. That would give me an extra 15mm; but I am contemplating competition in rallycross and I think coilovers would be my best bet there if they have the adjustment range.

My RX-8 is a daily driver, so ride height is the more immediate concern; but not gutting the underside during rallycross competitions would also be nice.

I have a set of 09 spec Konis for sale. They are adjustable and give a good ride on the softer settings. They will also handle way better than stock Bilsteins.

What about H&R coilover is't gud or bad??

You know i drove my 8 for three years before i did anything to it because i wanted to fully maximize its potential. Now after extensive research on my own part i purchased Tein Flex coilovers and in 2006 they just happen one of three top brands to buy at that time. Since the day i put them in my self november 2006 i have never had any problems with them. I have not had an alignment done since then as well. I have ran my 8 to the ground on the street in the mountains you name it. The handling, response, feel of the road completely changed for the better. Ive driven 18 times between kentucky and colorado (im military) in my 8 and it feels just as good as when i had my factory tokico coilovers. Every one is different but just because some poeple say they dont like then dosnt mean its crap. Tein has been around for decades and if they were crap they would not have been stayed in buisness so long. Go google Tien and read there history on how they came to be. One of the top respected names in the suspension world in Japan. They have proven their worth in every aspect, and style of auto racing there is. I will put my 8 against any other car when it comes to cornering and handling. I swear by Tien but thats me. It has taken even the most well known proffesional drivers up to a few years and couple of thousand dollars to find the perfect and right suspension combination for them. The bottem line is as long as you know what you want and how you want to apply it track, strip, show, daily driver you get what you feel fits you the best. Read the reviews see what others who actually have used them think an feel and not just by word of mouth. I hope this helps you on your quest for the right set up for you God Bless!

I want to go low on my 8, do you know how low you can go front and rear on these ? these will still handle better then stock suspension tho right ?

You will sacrifice comfort if you lower the car to the max on those coilovers. The answer is positively NO!

I guess I'll bring this thread back to life.

does anyone know anything about these?

D2 RACING RS 36-STEP ADJUSTABLE COILOVERS

I went through all 5 pages of this thread and saw maybe one person mention them but had no info about them.

for my application I would like to lower my 8 but still have close to stock comfort if that's possible. I wont be driving on track, this is just for your everyday daily driven rx8. I also see that a lot of people are saying megans are a good for daily but i don't want something so cheaply made that all they are good for is lowering. Really just looking for something in between, all the comfort of stock but can achieve that lowered stance.

I had the D2 coilovers and they sucked. Blew a shock shortly after. I'd suggest against them.

I have Stance GR right now and they're ok for a street car. If you're looking for a stock~ish ride I'd prob reccomend looking at the Tein street basis or basics, whatever its called. I test drove a friends 8 with them and loved the ride for street driving.

Its comfy. Granted they're a cheap coilover, they dont have damper adjustment and don't goo too low, they were almost identical to stock and he was pretty low on them.

Stance GR+. Great improvement over stock. even better once I got sways. Easy to soften up for daily, easy to tighten up for aggressive driving. Crazy amount of thread on them for slamming if that's your goal.

I'd say they gave me my moneys worth.

Posted From RX8Club.com Android App

Yeah Stance are great on street. I replaced all 4 shocks after having a leak on one front and one rear shock. Bought them used with low miles but talk about double spending lol. They're awesome with sway bars too. Sway bars made the big difference to me.

Stance blow (I have them).

https://www.rx8club.com/series-i-whe...-links-207346/

And about how your Stance/powertrix will lose the rear bushings in under a year and if you bought them used they are probably already cracked.

https://www.rx8club.com/series-i-whe...inions-232656/

I like my KW V3's, but I got a deal on some very lightly used ones, I didn't lower the car much and I go to the track, so my use is a bit different than yours. That said, the ride is a fair bit better than my old FC RX-7 with Tein Flex's with 7kg/mm front and 5 kg/mm rear springs (different motion ratios, so you can't make direct comparisons of spring rates).

Anything that I purchase and consider nice (especially after spending 1k+), I can always count on 9k to come and rip it lol :dunno:

Sorry man, it is what it is. At least you guys have the benefit of previous knowledge. But if you still choose the wrong path then that is on you.

Still happy with Stance:ylsuper:

Same here. I'm satisfied with them. Been keeping an eye on the lower mount bushings.

Ignorance is bliss. I was too until I experienced real coilovers properly setup that don't come apart in 6 months.