MikeTyson8MyKids

iTrader: (1)

I don't think the Autox spring ever happened, but they did make the normal street spring. They had about the same rates as every other lowering spring.

Eric13

Ah okay. Any recommendations on some springs for say some Koni shocks? I'm looking at getting some, currently I'm all stock. I will be buying a Progress front bar in a couple of weeks as well.

TeamRX8

iTrader: (25)

Unless you buy or make a coilover conversion your options are the usual bunk ....

MikeTyson8MyKids

iTrader: (1)

Eric, just put to what Mark says in perspective. I had on d-specs with progress springs with assorted bars. This seemed pretty good, I pretty much won my class 100% of the time anywhere I went at a club level and pax out in top 3. And then I put the Eibachs on, and it is just simply many times better in all ways...and these aren't really considered top notch either.

So in all...is something like a koni/spring combo better than stock? Sure..in fact thats what we're doing on the friends car we're slowly building. He's new...learning quickly, but new. A top notch set of coilovers is probably not needed at this point.

If you feel you are at a point that a good set of coilovers will benefit you, go for it.

Eric13

I really just want something competitive with a small budget that will hold me over until the end of the year when I make my switch to an Evo X. So a shock/spring upgrade makes more sense to me budget wise. Coilovers will be bought for the Evo for sure.

TeamRX8

iTrader: (25)

The info on all those springs has been discussed to death on the forum

TeamRX8

iTrader: (25)

https://www.rx8club.com/series-i-whe...on-info-79096/

ABQautoxer

So much for waiting for 2015 to jump to STX. We hit our self-imposed deadline for the Mineral Wells Pro and Street AWD never got anyone else registered so we're jumping ship from the TT to the RX8 which means we'll be bringing it to Spring Nats as well. So far we only have done the big suspension items. I don't think I'll have the time by TX to get an intake, exhaust, and matching tune done. We'll likely use Rivals from last year as well off the WRX. So far we are the only 8 registered in STX.

Nathan Atkins

at the DC Pro this past weekend RX8s topped both CS and STX, they were the only RX8's in their respective classes, one of these days im going to get my car properly prepped and get out there and be competitive :-)

Here are the Trophy winners:

Class standings for CS [11 Cars] (03:27:44 PM)
-------------------------------------------------------------------------------------------
T 1 161 Mark Andy 2005 Mazda RX-8 Red Hankook RT/60ft
32.766 32.766 35.145(1) 35.150(1) 33.472 33.359 66.213
34.153 33.609 35.243(1) 33.741 33.447 34.782(1)
-------------------------------------------------------------------------------------------
T 2 57 John Laughlin 2013 Subaru BRZ Silver Dunlop* RT/60ft
34.498 33.219 33.410 32.978 33.022 39.177(3) 66.851
34.934 34.549 RL 34.156 34.533 33.873 (0.638)
-------------------------------------------------------------------------------------------
T 3 11 Mike Ferchak 2013 Scion* FR-S Dunlop* RT/60ft
35.780 33.757 33.459 33.628 35.924(1) 33.185 66.987
RL 34.672 36.702(1) 34.476 36.382(1) 33.802 (0.136)

Class standings for STX [18 Cars] (03:28:11 PM)

-------------------------------------------------------------------------------------------
T 1 91 Jeff Hurst 2004 Mazda RX-8 Black Hankook RT/60ft
32.990 32.222 32.724 32.086 32.899 36.358(2) 64.763
33.581 33.309 34.252 32.955 34.887(1) 32.677
-------------------------------------------------------------------------------------------
T 2 197 Jeff Anderson 1993 BMW* 325is Green Hankook RT/60ft
RL 32.426 32.478 RL 33.233 32.142 64.956
33.412 33.456 33.586 32.861 35.892(1) 32.814 (0.193)
-------------------------------------------------------------------------------------------
T 3 97 Bob Davis 1993 BMW* 325si Green Hankook RT/60ft
43.002(3) 33.267 33.081 32.918 35.228(1) 32.254 65.065
45.775(0,1) RL RL 33.719 32.811 RL (0.109)
-------------------------------------------------------------------------------------------
T 4 48 Sir Van Townsend 2013 Scion* Pollo Itali Multi RT/60ft
35.994(1) RL 35.440(1) 33.184 34.266(1) 32.341 65.404
35.940 34.306 34.079 33.415 34.434 33.063 (0.339)
-------------------------------------------------------------------------------------------
T 5 116 Michael Bombard 2013 Subaru BRZ Gray Multi RT/60ft
35.818(1) 33.400 32.647 34.451(1) 34.482 33.059 65.452
37.537(2) 33.201 34.010 38.168(2) 36.110(1) 32.805 (0.048)
-------------------------------------------------------------------------------------------
T 6 16 Eric Simmons 2013 Subaru BRZ Grey Multi RT/60ft
33.043 32.690 33.034 32.561 32.891 32.380 65.786
36.276(1) 33.487 33.406 33.546 RL 35.137(1) (0.334)

ABQautoxer

Mineral Wells this weekend will be rough with Craig. At least we'll find out how far behind the eight ball with are with my minimum prep'd car we are.

marka

Howdy,

Eh, get yourself out there now. "Properly prepped" is a myth / overrated. Everyone preps to the best of their abilities in terms of time/finances/whatever. The driver is still what matters the most.

Mark

Nathan Atkins

That is true, that said my car is not just Unmodded but lacking certain uhhhh refinements. Such as rust free camber bolts that rotate...putting more than 154whp to the ground...having rubbish OESpectrum replacement shocks, that sort of thing.

I do the best I can with it and I've had some pros (guys like Danny kao, mike Moran, Andy Thomas to name a few) codrive the car many times and have only been beaten in it by them once. So I think that I'm getting some 90+% of what the car has to offer out of it and still place middling in stx(a class I run in to be in friends run groups)

But I graduate with employment in a few weeks so I can funnel some cash into prep, then I can fully utilize some of this talent I'm using to make up for the cars deficiencies :-P

TeamRX8

iTrader: (25)

Congrats to Jeff Hurst for a strong STX win at the NJ Tour

ABQautoxer

Impressive margin for Jeff indeed. TX wasn't a disaster so we'll be trying to get the car in better shape for Spring Nats.

Nathan Atkins

So I'm curious, why is it, that when our weight distribution is ~52/48, and front and rear motion ratios are pretty close as well, that you always see rear spring rates that are so much higher in the front than in the rear on basically every off the shelf coilover kit for the RX-8?

I just wonder this because it seems to me that they are just basically scaling up the stock front to rear spring stiffness, but it seems like for autocross you would want them to be square given the relatively even weight distribution, and a desire to have a slightly higher rear natural frequency.

The common argument is that that's what the winners are using so just go with it, but it's pretty clear this logic is flawed, i routinely stomp all over people in superior machinery in my 8 and it's not down to mechanical setup. Winning doesnt necessarily mean its right, and i wonder if any of them have tried a more square setup?

I'm just curious if anyone knows enough about the behaviour of the car when on square springs versus front biased to comment about it. I'm not looking for Argumentum ad factum :-) Just a technical discussion.

TeamRX8

iTrader: (25)

The loads experienced by the front and rear suspension are significantly different. The non-OE rates are typically not proportional on the RX8. The front rate typically increases more than the rear rate, though the sway bar choices also have to be considered as well so I am referring to actual wheel rate not just the spring rate.

If you can make a square setup work then more power to you. It will more likely be quite the drift car.

Nathan Atkins

The intent was to do 475 square with no rear stabilizer bar, I'll get bounce frequencies of 2.1 and 2.2, and a front roll couple of 60%

I'm using Fat Cat's spreadsheet to figure this out:
FCM_MSDS_RX8.xls

So assuming it's right, that is a similar FRC to stock, and the sort of bounce frequencies that Far North is always bleating about to be ideal for autocross:
Autocross to Win (DGs Autocross Secrets) - Suspension

So I get 475 front and rear, remove rear stabilizer bar, valve shocks for 65% critical and hey presto, it's theoretically good then right?

I dont know maybe i'm missing something but these guys seem to know what theyre talking about, I'm going to put a set together and see what happens, I'm getting standard 2.5 inch race springs so if they dont work I'll try something else, lots of options in that fitment.

When I get them and put them on the car I'll post up some data for you guys, for better or worse.

TeamRX8

iTrader: (25)

Well there are people running no rear bar with higher front rates, but let us know what your experience is trying it

JeffH

Never really understood the use of spring frequencies in an application where sway bars play such a heavy roll in our suspension. The moment you're not going straight or hitting a bump evenly all that data is out the window.

Another factor not taken into account if one were to calculate the bounce frequency is tire spring rate (https://www.hoosiertire.com/spring.htm) All tires are different. Unfortunately you won't find this data for street tires.

Don't be afraid to try different spring, bar combinations to find what works best for you.

JeffH

As Team mentioned, you'll end up with a very loose car. It would work great in a no engine braking or throttle input scenario with rear active steering. At the end of the day your asking the front and rear tires to perform different tasks. It's a about compromises.

JeffH

Thanks guys. Nice driving yourself Tom. I'm sure Craig was looking in his rear view on the way home.

It was a lot fun for us with back to back weekends. Felt like I'm finally getting back into the groove with the long winter.

DC was a serious challenge with Anderson there. Courses were typical DC Pro style, not many elements other than dealing off camber lot. Be tidy in some areas and ***** to the wall in others. Layouts that at the end most likely favored individual car strengths than drivers. The RX-8 being good in all worked pretty well. Plan was to see how the R1R's worked out to get started. After moving into first I decided to see how well the V2 RS3's would work. First time on the 255's so made a guesstimate with changes and ended up dropping some time after adjusting the shocks between runs. Found out they do like some heat but not much. They seemed to work once they clear 80 degrees or so.

Came home with a close win after having speed up on my last run to stay in the lead.

Going into NJ I was determined to lay it down from the start of the event. With some back to back testing on the practice course and the tires being close in times I chose the R1R knowing it would be windy and cool when we ran. They were on their last legs from Nationals but figured with the surface being kind on tires I could make them last. Courses were laid out in a way that they were long and challenging.

Day 1 right off the bat, the car was close to perfect. Loose but it worked well on the decreasing radius corners. I was hoping to get a clean 64.x to narrow the gap to STR times but I kicked a cone when it stepped out. Was happy with the result but wanted more.

Day 2 didn't go completely to plan. l did get a solid first run (66.0) that I felt would hold the lead but that's about where it ended. And that's where the reruns started. After first run of being a bit tight with my hands and throttle I wanted to open it up. Came to the finish after a great run 2 and there was a cone in the middle of racing line for the finish. I decided to stop since it was a tight 90 and there wasn't much chance to miss it without going offline. Getting what felt like less than 5 minutes went out thinking "That was perfect run, how can I do it again?" Well I tried, with hotter R1R's this time, didn't do it as good but close and then kicked the finish cone. Run 3, felt really good, may have been the best. Well this run, the guy who took out the finish last time didn't go through the lights. No time.. so back to spraying tires with the hopes of getting into the 64.x's. Well ended up going slight faster than the first with a 65.6 but didn't feel the best.

Thinking back the car was pushy compared to day 1, I just let the re-runs get the best of me and didn't stop to think about what the car was doing. Front tires were below 2/32 and pretty much done at this point to. So back to RS3's for the rest of the east coast season.

So it looks like the RX-8 can still get it done.

TeamRX8

iTrader: (25)

amen ...

Nathan Atkins

It'll take me a few weeks to get everything ordered and assembled, but we will see what happens, i'll be running data acquisition and I'm going to experiment with different spring rates if needed.

I'm doing the WDCR SCCA solo event at FedEx will likely be the first event with everything installed. It's a competitive field at WDCR for STX so I'm hoping to be within the top 10-15% or so, and I'll get it dialed in from there.

I am interested in what you guys have deemed worthwhile for power upgrades, as my car only put 154 to the wheels when last i checked it. :-( I'm loosely planning a compression test to gauge my engine's health

Kennetht638

iTrader: (2)

While I'm not one to discourage experimentation, I also wouldn't ignore all of the evidence of people running spring rates with a heavy front stiffness bias. I'm also with Jeff in that I think the natural frequency doesn't tell you much because of the contribution of bars. On my car, the roll stiffness contribution from the bars is very significant compared to that of the springs.

Additionally, the natural frequency rules of thumb that you cite are seriously simplified. There is a lot of stuff going on with passenger car suspensions that isn't accounted for there, like camber/caster/toe effects with compliance and roll steer that you likely don't know the magnitudes of.

Anyway, you are absolutely free to try what you want. I just don't think you should do it because somebody on the internet said that you should follow this rule without giving it some serious thought. You also shouldn't just listen to the rest of us blindly either, so good luck and I look forward to seeing how it goes!

Nathan Atkins

Thanks Kenneth,
With the rear bar disconnected/removed I should have the same FRC as stock on the my springs, so understeer/oversteer balance might be similar. Who knows maybe it will fail miserably and I'll try a more typical spring setup, I'm all about posting some fresh data though, and it shouldn't be too hard to unload a pair of hyperco 10B475's on eBay :-)