Spin9k

I am trying to decide on winter mods, one being new sway bars/springs. My purpose is to improve the car for Track Days next year. With our power improvements pretty much limited to minimal, obviously handling improvements seem next and will allow higher corner and exit speeds to carry on down the straights (given a capable driver, of course).

I've got the winter to figure this out/decide so here is the info I've gathered (by contacting Racing Beat & MazdaSpeed on sway stiffness) and now I'd appreciate thoughts from others with either experience doing this or just those witrh a questioning analytical mind contemplating the same thing. Perhaps, if we are lucky, even MS or RB can comment on their design philosophies as I've never seen them stated on their web sites or anywhere, surprisingly.

I know there are many combos possible with different springs/sways/coilovers, etc. but the MS & RB pair seem to exemplify the problems we face in deciding where to put down our cash, and hopefully only needing to do it once, not over and over, trail and error fashion.

Although I see lots recommending one or the other, most also recommend staying with one brand when a spring/sway mod is done. But I was wondering about mixing, so I called and got the info on the two sways in question. With those specs, I can plainly see they are really totally different, and mixing likely (?) not an option.

This spring info is from a thread https://www.rx8club.com/showthread.p...t=spring+rates on 'spring rates' which shows

Stock RX8 6spd
F 155.61 lb/in
R 112.86 lb/in

Mazdaspeed Spring ....................................... .Mazdaspeed Sway
F 280 lb/in (80% Stiffer vs Stock 6spd) .......... .17%-20% difference (as stated)
R 190.4 lb/in (69% Stiffer vs Stock 6spd) ....... .34% difference (as stated)

>>requires MS strong shock for strong springs

Racing Beat Spring.......................................... .Racing Beat Sway
F 187 lb/in (20% Stiffer vs. Stock 6spd) ......... ~218% difference (given as 2.18 times as stiff)
R 136 lb/in (20% Stiffer vs. Stock 6spd) ......... ~198% difference (given as 1.98 times as stiff)

OK, so it is easy to see that MS and RB take two totally different approaches to handling improvement. In general then we can see:

Racing Beat = very mild spring/stock shock, strong sway
Mazdaspeed = strong spring/shock, very mild sway

The discussion I would like is:

1) How can two arguably great race development teams come up with such a different plan of action? People who have one or the other say they really like them and it improves handling a lot. I don't hear much difference in reviews. Why has this happened?

2) Do these two approaches REALLY achieve the same result? By that I mean **in using the car where one could likely notice and appreciate the difference --- on the track***? Are there actually major quantitative handling differences?

3) It begs the question, if they are the same, then is the RB the 'Best Buy' as it does not require new shocks, yet achieves the same result? Or did Racing Beat just go the 'cheap & easy route' to get maybe 50-70% the improvement of the MazdaSpeed.

4) I had heard and read that the place to start handling improvements was in the springs (and shocks to match) first, then add sway changes (maybe) only to fine tune. This would seem to favor the MazdaSpeed (corrected) setup as it goes heavy into shock/springs, with minimal sways, yes?

If we can come to some conclusion, I'll be able to spend my money, and get the result I need. Maybe you will too. Thanks for your thoughts in advance.

Spin9k

MS = MazdaSpeed
RB = Racing Beat

RX8-TX

Like you said, they took 2 different approaches: While the RacingBeat springs will not change the everyday driving characteristics, it should stiffen up the chassis on hard cornering. And while the MS higher spring rates may be somewhat punishing for everyday use....they will make the 8 feel more planted in most every condition -until you drive by a big bump...

Red Devil

This is a good thread...

I've been going between the two brands also for suspension upgrades. I've been thinking JIC or Tein will be too stiff for my everyday driving and that RB and MS are a more moderate adjustment to the car.

I having been leaning towards RB only because they are much cheaper, and I can't myself quantify which is better than the other.

Jaguar

Racing Beat is coming out with a set of adjustable Koni's (listed on their site). From what I understand is that the original shocks cannot handle an increased load of a stiffer spring. That may be why Racing Beat's spring rates are a little on the softer side. I am willing to bet that once they come out with the Koni's they will come out with a set of stiffer springs. The aftermarket industry really hasn't embraced the 8 yet. I personally have the Mazdaspeed shocks and springs along with the Racing Beat sway bars. They both work beautifully together. There is only a slight change in ride.

Relentless

Roger --

Racing Beat's sway bars are more aggressive, while Mazdaspeed's spring/shock combo is harsher. I think the Racing Beat setup is probably a better value. But if you're looking for max performance, you might consider looking into coilovers.

The best and single most important upgrade you make is tires, so you might as well get the best tires (I'm actually about to go ship them in a minute).

By the way, if you're looking for a noticeable power upgrade, I am selling my Mazdaspeed flywheel, as I got the Unorthodox Racing one for free for the mag story (should be out this month) and that is what is sitting in my tranny right now. the MS flywheel was the first thing I did after the exhaust, and so far really is the only thing to result in a noticeable improvement in power delivery (the pulleys I just installed aren't half bad either).

Just thought I'd give a heads up.

Jeff

RotorManiac

I have the MS sway bars. For the moment, its the only mod I did in the suspension. I have to say there is a small change in body roll, which is less than stock.

The car now is more nervous when going over bumps, but the overall effect is really good (considering I chanced only one thing, and haven't touched the springs/shocks yet) I don't know about RB, but from your info it should be a great product for someone who doesn't want to change anything else, just to make the body roll go away.

I know that I'm going to keep modding my car, so I didn't want a very stiff sway bar. This is because I am considering the TEIN flex (with EDFC) coilovers, which a friend of mine has, and told me that they are VERY stiff, even at minimum stiffness option:o I'm saying all this, keeping in mind that you DON'T want to loose everyday drivability of the car... if you want an extreme setting, that's easy!!

p.s. you guys have any comments for the tein/MS sways&struts combo?

Spin9k

Stiff springs, strong shocks and stiff sways . That sounds really tight Jaguar! I've never heard anyone beside yourself doing that. You say the ride is only a little different which is great to hear - I would have thought you'd shake your fillings out with that setup on any rough road!

But most important have you done any track days using that gear? If so I wouldn't mind equisite detail on how your 8 now responds to things like trail braking, off camber turns, 180's, S-curves, all that good stuff and more if you'd care to share!

Genom

lourx8 has the front and rear RB sway bars, Alexcisneros has the F/R Tanabe bars, and I have a racing beat front and tanabe rear. I will say th RB stuff is much softer than the tanabe. If you want to improve your track days, and not just mild autocrossing, I would say go with the Tanabe. Dunno how stiff the MS bars are, but the tanabe's are noticeably stiffer than the RB. If the MS are that stiff, they should work great.

GeorgeH

iTrader: (2)

This is an interesting question - do you put the roll stiffness into the sways, or the springs? Sorry in advance for the long response.

The advantage of putting roll stiffness into sways is that the change in bump stiffness is halved, as compared to the same change in roll stiffness from springs. The disadvantage is that you tie the two wheels together more strongly, which can actually hurt grip over rougher surfaces. So, think about that. Over rough surfaces the car with the stiffer springs will ride rougher but may actually have more grip.

The advantage of putting roll stiffness into springs is that it makes the whole car feel more responsive in roll, squat, and dive. Whereas the bars only affect roll.

At some levels, it comes down to a personal preference. I’ve had my Miata in just about every combination possible. Stiff shocks with soft bars & springs, soft springs & shocks with stiff bars, stiff shocks & springs with stiff, soft, and even no, bars. And personally, I like the affect of stiff springs more than stiff bars. I really like the way they make the car respond – all inputs are met with less body motion, as opposed to just the steering wheel. It gives the car an overall edge it never had before. But then the ride quality is never what is once was (but I run spring rates that are 2x or more than stock). More boy-racer than suave cruiser. What do you want?

One other thing to keep in mind in all this is your wheel/tire package. I have found that stiff sways do not agree well with heavy wheel/tire packages. Which is to say, you will notice the coupling affect of stiff sways less if you have super light wheels & tires. If you are planning to go with staggered 19” setup, I’d strongly recommend the MS setup. But if you are going with 17 or 18” SSR Comps then the effect big sways won’t be so apparent. Also, turn-in should be considered. I’ve found that tires that have soft turn-in, such as Toyos, will feel better with stiffer sways.

Just to tell you where I am coming from, my all-time favorite setup on my Miata is no sways with the GC coil-overs and shocks set to full stiff (necessary since the spring rates of the GC kit stretch the damping ability of the Illuminas) with Falken Azenis tires. The Azenis are heavy, but boy do they grip and they turn in RIGHT NOW. Coupled with the K1 wheels, the unsprung weight was just the wrong side of “too much” and with sway bars attached, even OEM, the grip over rough roads was compromised and there was too much cowl shake. When I detached the sways the car completely changed. Turn-in was still fantastic, body roll was still much less than stock (due to the stiff springs) but what was amazing was the feeling of having a stiffly sprung, very responsive car that was amazingly supple. My reaction was “So this is what a truly independent suspension feels like.” I could feel the difference when just piddling down a neighborhood street, or when charging along a bumpy country road.

Which brings me to my current Miata setup. I got my hands on some used SSR comps, and decided to go with Toyo RA-1s. The Toyos NEEDED the sways – otherwise, there was a big dead spot when the steering wheel was centered – no turn in. However, with the lighter wheels & tires, I didn’t notice the coupling effect of the sways so much, although the car still isn’t as supple as it once was. When the RA-1s wear out I’m going back to the (newer and lighter) Azenis and no sways, at least for the street (Track & autocross is another thing).

So, that’s my experience with this question. Heavy wheel/tire package = big sways bad. Stiff sidewall tires = big sways not needed. Light, soft-sidewall tires = big sways needed. For me, I suspect I would like the MS package better than the RB package. Keep the wheels light, the sidewalls responsive, the sway bars small, and the springs & shocks matched, with stiffness as per your preferences. Handling nirvana.

George

Relentless

I actually have the Tein Flex, and the ride is less harsh than the Tanabe GF210 spring/stock shock combo had before. The sway bars let you feel the bumps more, but swapping out to the Michelin PS2s (2 lbs lighter than stock) vastly improved ride quality.

You should probably do the sway bars before springs/coilovers. The setup I had before the new 19" rims (MS sway bars/Tein Flex coilovers/stock rims and Michelin PS2s) offered pretty good ride quality and little body roll. You might also consider getting a set of lightweight 18" rims (as GeorgeH mentioned, I think the 18" SSR Comps sound great at about only 16 lbs each).

Jeff

RotorManiac

Jeff, the PS2's don't come in stock dimension. I know its a great tire, but a few dealers I asked told me that there's no 225/45/18. by the way, I think Toyo's are very light tires...
thx for the info, I'll go for the teins...

Relentless

Get the PS2's in 245/40/18. It is slight lower sidewall height (like 3mm), and wider for better grip.

brillo

I've driven and installed both (I have a thread on that somewhere) since you say your going to track the car, I would go Mazdaspeed. The MS are a little harsher, but, at the limits (when you say track I assume a real road couse, not autox) the MS will keep the car more stable, especially at high speed. I can take corners flat as a board at near insane speeds, and the tires give up long before the suspension.

Don't get me wrong, I think the RB is a great setup for anyone who wants better street handling and non competive track/autox use (in other words just for fun), for most people RB is the better choice and cheaper. I'm really into the autox/track stuff more for fun than anything, so in retrospect I wonder if I should have gone with RB. That said, this factory match suspension is hard to beat, and the ride quality is still quite good.

Now if your just tracking the car once and a while for fun, RB will be fine. I just don't know how serious you are.

Spin9k

I guess you could say I'm seriously having fun and can't stop. So more NASA track days and weekends are the focus for next year I'd say. I might be a bit of a fanatic and therefore want to make my 8 as good as possible on track, but still streetable. It was way to easy to see where it was a little weak this last year, namely the tires/suspension and the lack of serious power in hi-rpm 3rd and all of 4th gear... not that it wasn't a blast anyway .... but...

So far for the suspension - I like the concept of jaguar's setup (MS spring/shocks and RB sways or smtg like that), although he hasn't told us how it worked yet (still out there jaguar?). Then likely 17X8.5 SSR comps & 245/40x17s (like BFG KDs) for a little more 'near race' rubber, also giving an added 1/2" drop for a 1" total including the MS springs ~1/2" drop.

For power then the smaller tire diameter effectively giving a 5% lower rear axle ratio... Add in Canzoomer S1 for yet a bit more omph and I might be done cause of how much just that is all going to cost. It should be markedly superior to stock in any event I think.

But w/more $, a highflow cat and Stage 2 would be nicer yet... you see how easily it is to add the 1K$ bills to the total? Damn!

Jaguar

Spin9K,

I haven't had the car on the track yet. I drove the car from here in Cleveland, OH to Florida and back and it was extremely comfortable. It does handle much better that stock, not as floaty. The only drawback that I have encountered is a tad amount of understeer. Not much, but a tad.

rev-2-9k

i don't think either are competition quality. the RB really needs some adjustable Koni's, and i will get them when the stock shocks are replaced at 50k or so.

my RB setup's weakness is the stock tires. the MS shocks are marginally better but not adjustable. if they were the MS suspension would have appealed to me more.

Spin9k

The latest RX-8 MazdaSpeed II has MS damping and height adjustable shocks here http://www.mazda.co.jp/customize/rx-8msv/chassis.html roughly translated as

"The shock absorber whose +8mm - -20mm attenuation power adjustment of height adjustment and 4 stages is possible -. The sport spring which administers the rise of spring rate. Quick with the item which makes the corner ring possible, being sharp it is the quality where RX-8 is superior, while raising the maneuverability which has the sense of security, it actualizes the compatibility with the riding comfort."

Ok. Whatever...? I tryed several ways to find out exactly what that means It = <4-step damper adjust with +8 to -20mm height variation coilover> supposedly. I am not convinced these are available yet to the general public - short of buying a MS II RX-8. When they are, hopefully they will be a value MS coilover set allowing us some adjustment, perhaps just not 15 or > way. The modest height adjustment perhaps will spare us geometry/alignment issues. If they're like current design it will be a moderately strong damper/spring set.

KISS - Hopefully this will be a real item! All I want is some somewhat adjustable spring/shocks, reasonable$, yet matched to the car and each other for performance driving. I don't have a racetrack at my disposol to fine tune so much, even though i wish I did LOL!

PUR NRG

There's some interesting knowledge in this thread. There's some interesting misinformation as well. My comments in no particular order:

1. The MS setup includes shocks, while the current RB doesn't. So you can't compare spring rates and sway bar stiffness alone.
2. Upgrade order should be wheels, tires, springs/shocks, sway bar last. Ideally you want to tune the springs/shocks so you can run the least amount of sway bars possible. Way too many people recommend doing sway bars first because they're the cheapest and easy to install.
3. "Mild autocross"? There's a contradiction in terms. I do both track days and autocross events and autocross will test your car's suspension limits more severely than the track. Track events are harder on the engine and brakes.
4. 1+4=5. 2+3=5. With so many different factors you can tweak there is more than one way to achieve the same result. Unfortunately the assumption that MS and RB achieve the same result is incorrect. Maybe one considered quick transitions more important while another emphasized initial turn-in. Suspension requirements for road, track and autocross are different. One mechanic expressed horror when I said I wanted some front toe-out. In his world that was the worst thing you could do for road driving. He's correct but I wanted it for autocross.
5. It will take a lot of time, money and knowledge for someone to experiment with all the different parts and determine which is better for a given application. Unfortunately we aren't there yet. People (including myself) who try only one upgrade path don't have a basis for comparison to say their route is the best.

My setup: JIC FLT-A2s with 560 lb/in springs in front (359% stiffer), 392 lb/in springs in rear (347% stiffer), lowered 3/4" and then corner weighted. RB front and rear sway bars with heim joints to eliminate preload. SSR 18x8.5" wheels with 245/40 Bridgestone S02 tires that will soon be replaced with Michelin PS2 265/35s.
________
Hiace

murix

I do fine on the track with my RB setup but it by no means is the ultimate track setup. If my primary concern was only track use I would have went straight for the MS setup or ultimately coilovers.

I find the RB swaybars/springs combo to be a really good street setup that handles back mountain roads well with the ability to hit the track when I want to. It is a compromise in handling vs retaining stock ride and comfort. On the track, I think I need more dampening, but that is probably just a personal preference.

Jaguar

The original and MS shocks are Tokico which is a pretty reputable company. I chose my setup based on just a fun factor without a compromise in ride. I figure that I won't be racing around here. I may take it to the track one day just for fun. If you are going to the track the coilovers would be ideal to adjust the car and take advantage of the 50/50 weight. I don't really understand the idea of changing the tire/wheel setup too much other than for looks. I am not sure where Spin9K lives but you can check the forum for someone nearby and ask to take a ride in their setup. Might help with your decision. That's probably the best way to chose the right setup for you.

PUR NRG

Wheels: if you can get some that are lighter than stock, it's a performance benefit. Look up sprung weight vs. unsprung weight. If you can get wheels that are wider than stock (but still the same weight) you can fit a wider tire w/o rubbing and it's a performance benefit.
Tires: sure you don't understand the performance benefit of different rubber compounds or widths?
________
Mercedes-benz type 300 history

Spin9k

Looks is the last reason I'd change rims as I think the OEM are quite good enough and certainly not bad enough looking to waste money on changing for looks alone (pls no flames, just MHO). However, there are very good reasons otherwise though so...

Tires is another subject ... there are plenty of performance reasons to change tires. For example, to get stickier tires, quietier tires, bigger contact patch tires, tires better suited to track or auto-x or just for driving around. That is kinda a no-brainer and there are places like Tirerack testing, Grassroots Motorsports, people's experience on this board, etc., with lots of thoughts on some options.

Jaguar, here are a couple threads to get more info on the why and how to change the stock tire/wheel setup to [performance] advantage . I look it as a doable way to get more performance (speed, acceleration) vs the so far iffy and un- or under- realized ideas to actually increase HP & performance in a straightforward way (at the engine level). Some good reading here if you are so inclined, and the reason I'm planning on doing the tire/wheel change

https://www.rx8club.com/series-i-wheels-tires-brakes-suspension-55/stock-18inch-wheel-weight-analysis-46728/

and perhaps the ultimate thread on the tire/wheel performance subject:

https://www.rx8club.com/showthread.p...smaller+wheels

Fanman

Actually you can decrease stopping distance far more from swapping out a higher grade/performance level tire than bigger brakes. If you had a 245 BF Goodrich Comp TA KD/Michelin Pilot Sport 2 vs. a 225 Bridgestone Potenza RE 040 I bet you could take a good 5-10 ft. off stopping distance. More contact patch & stickier rubber. The weak point on this car is the tire, not the brakes.

GeorgeH

iTrader: (2)

I completely agree with this, and wanted to emphasize it again. Seemed far to important to leave it in the middle of PUR NRG's excellent post.