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Cwaters 01-13-06 08:27 PM

suspension for CSP?
 
Ok, without getting everyone's panties in a twist about technical terms, I think I need some advice on the direction I need to go.
I've got some twelve+ year old Koni yellows up front and Tokico Hps in the back. Stock springs (now TWENTY years old...sheesh.) I've been getting my ass kicked in ES for ever. The MR2s and 1.6 Miatas are too much for my crappy driver and tired old car.
There are things I've been wanting to do to the car but have been prevented by ES rules and, more importantly, money.

GOAL: To have fun. Not even expecting to podium locally but would like to be competitive if there are other cars like mine in the class. Would also like to do some track days.

So, I'm not totally legal at the moment but if I get coilovers or new springs, I'll feel bad enough that I need to switch to CSP even though it's not going to propell me into the top ten even in ES locally so I doubt they'd really care. The car isn't a daily driver but will be driven to events. I'm planning to lighten the load a bit but not sure what else I can pair down.

The Konis are tired but not dead. I've been feeling like the car rolls more now though than it did the year before and the year before that.
The HPs out back are pretty new, only a couple thousand miles on them.
I don't have the money to get new Konis and coilovers with a camber stick out back and plates up front at least not all at once. That would take two or three years, depending one what brakes on the car.
Should I:

Get KYBs all around? They're cheeper than new Konis. Maybe I can also get some aftermarket springs too but that's a stretch.

Get new Konis. Certainly need to keep the stock springs for a year and hope the motor doesn't go.

Keep the shock set-up and get

Just some springs?

GC coilovers with no other suspenion mods... What spring rates (oh boy) and are the rears going to be different since they ask you if you what shocks you have? What if I want to change shocks next year? Will I have to change coilover sleves?

Revalve the old Konis and get some for the back?

What about sway bars???

I know it's a lot to ask you guys but I really don't know where to put my meger fist full of ones... Sorry if I'm babbling like a dufus.


fire away.

DaveTurnerMotorsports 01-14-06 01:30 AM

Fresh Koni Yellows or Bilstein shocks, the Suspension Techniques 28mm front sway bar and bushings, replace your old bushings with new Mazda ones (or the slightly stiffer rubber Mazdaspeed if you think you can get away with it), align the car.

Tires. Tires. Tires. Tires. Tires. Did I mention TIRES?

Many people stuck in the Stock Class woe forget that just getting the car to as good as "new stock" will make the car reasonably fast in the right hands. Old/blow shocks and binding bushings can even be masked by a great set of race tires, but how much faster could you go if it all worked together!!

I wouldn't waste time with the coilovers. New stock-legal shocks, tires, and alignment will get you 98% of the way there.

I was planning on running the GTUs in E-Stock, but on the urging of several sponsors they would like me to run in a more prepared class (STS2) to showcase their products. But I will say that my car, properly set up and with a good set of Kumho V710's, would be faster in E-Stock raw time than on street tires in STS2. And more livable when driving it every day.

CSP is a slippery slope that leave many in more disappointment than they started with. You can spend plenty of money in stock class and GREATLY improve both the race and street drivability of your RX-7 and keep it in E-Stock.

Just a thought.

Exaust system
Full tune up (plugs, wires, O2 sensor, cats not plugged, good fluids)
K&N or Racing Beat stock-style air filter

Koni Yellows
ST front sway bar
Mazda upper strut mounts
Mazda control arm bushings, subframe mounts
Alignment

Brake pads, maybe new ss brake lines and good fluid.

Falken Azenis RT-615 tires on stock wheels, maybe a used set of Victoracers on another old set of stock wheels if you can.

Nice MOMO or Sparco steering wheel, shift knob if you'd like.


All of those things will make the car more drivable, still allow your tuning/tinkering mind to play, and be faster out on the racecourse. Also, a well-maintained car retains its value more than a "tired 20-year-old" with some coilovers, making your dollar go much further.

Black91n/a 01-14-06 01:41 AM

The FC will have a very hard time in CSP. There are many very fast miata's in that class, but you can at least have some fun.

For the first step I'd think that you'd want to get some Koni Yellow's for the rear and have the old fron Koni's rebuilt. That'll probably be the cheapest, and simplest way to do it, and since it's not your only car then you can afford to have it off the road in for the service. You can probably also sell your Tokico's to get back a bit of your investment.

For the next step you could get either anti-roll bars, or some springs or a Ground Control coil over kit. I'd suggest the GC kit instead of springs due to the ability to mix and match spring rates, and no stock replacement springs that I've seen offer a good rates without dropping the car to the ground. I've been looking at spring rate suggestions and have seen rates of 450/275, 400/275, and 350/225 all suggested as a good dual purpose setup. For roll bars there's some choice, there's Eibach, Suspension Techniques, Racing Beat, and Whiteline to name a few. The Whiteline ones are adjustable front and rear and are made in Austrailia and available in North Nmerica through PDM Racing out of Vancouver, B.C. Canada. They don't specifically list the FC fitment, but if you call them they can probably put some on their next order for you. I beleive the ST and Eibach ones are at least partially adjustable. I've got the RB ones and I like them, they give the car a nice balance, but they aren't adjustable.

After you get your stiffer springs and sway bars you'll need to tune the car to your liking in terms of oversteer and understeer by adjusting the roll bars and playing with the spring rates (GC).

To keep the costs down just keep the car at a reasonable ride height to eliminate the need for camber correction devices and set the desired camber with ride height adjustments (that should be possible, not that I've heard of anyone doing that specifically on an FC). You should also get the car corner weighted and align it to a performance alignment.

After that then you can get the camber plates and the rear camber link and lower the car more if you wish.

Once you're at that point there's not much left to do.

Make sure that you have good tires though, as they're THE most important thing for going fast. Also may I suggest that you may want to try STS2 instead, they require real street tires (wear > 140) and allow some fairly extensive suspension work (GC's, roll bars and Koni's would be legal). This helps reduce the cost of it all as the tires are cheaper and don't wear as quickly. For CSP get race tires. I'd think that 225/45/15's would be perfect on a 15x8 to get a smaller, wider tire for better acceleration, grip and a lower CG.

Anyway, these are just my thoughts on it, and that's basically what I plan to do, get Koni's then GC's.

DaveTurnerMotorsports 01-14-06 01:57 AM

If you HAVE to change your springs or put a header on, then STS2 is a much safer playground and eliminates the potential need for a second set of wheels, and all of the street prepared suspension rules and then some apply. You just can't run race tires or alternate fuel injection/ignition systems or change/delete the cats like in CSP, and you're limited to a 225 tire width and a 7.5" wide wheel.

-JW
89 GTUs in STS2

Cwaters 01-14-06 08:10 AM

Thanks for the thoughts!
Forgot to mention that I have a set of vert wheels with, if my hook-up is still racing and has tires to sell, Khumo take-offs to use. I even have a tire/tools trailer :)
I've replaced the front control arm bushings and all the sway bar bushings. I have the rear control arm bushings but haven't put them on yet. New front calipers and braided lines are in place with HP+ pads.

Honestly, I haven't looked at the STS2 rules. For sure the tires will cost more than I've paid my racer friend for V700s.

Cwaters 01-15-06 09:39 AM

So say I stay in stock class for now, I have the Koni's rebuilt and get new ones out back... (having a hard time with the thought of taking the struts apart again and keeping the stock springs but...it IS less money). Should I tell the Koni guys to valve them for autocross/track day duty? I won't be able to afford gettign the rears custom valved so...

New stock springs? What are the chances my springs are weak? I know there's some debate about the life of springs...
Exhaust.....corksport-type cat back and maybe a downpipe to eliminate my now hollow pre-cats?
fisnish my bushings job
Get a ST front bar.
new brake pads in back and a caliper if I need one.
and new take-off tires
That's my goal for this year I guess. Stay in ES, no springs.

Sound like a plan?

Of course it all goes to shit if the motor finally goes or I don't pass emissions again... but hey, we need a plan, right?

Black91n/a 01-15-06 03:30 PM

I don't know if re-valved shocks are legal in stock class, rebuilt will be fine though, but probably not with custom damping. I also think that putting in poly bishings would be illegal in stock class too. Doing any exhaust work is illegal in stock and STS2 with the exception of a cat back. Removing cats puts you straight into CSP. I've got a racing beat exhaust, it sounds good, is beautifully made, and is not too loud (you may get kicked out if you show up with a loud car).

I'd think for now, just get the front Koni's rebuilt, that way they'll match the rears. Don't bother with new stock springs unless you're dead set on staying in stock class, as it'll be a waste of money when down the road you want stiffer springs or coilovers. That said, your springs are probably much shorter and somewhat softer than when new.

In the end, it's up to you to class your car and it's up to your competitors to protest you. I think for small things that should bump you up a class aren't that big a deal as long as it's not helping you gain an unfair advantage over your competitors.

I'd say to take it slow and do mods as you can afford them, while not neglecting maintenance and such. This way your skills will progressively increase along with your car's ability and you'll get a better idea of where you want to go with it.

DaveTurnerMotorsports 01-15-06 10:42 PM

Revlaved shocks are completely legal for SCCA Solo Stock class in the US. You may run any off-the-shelf non-adjustable, adjustable (two way-- rebound and compression, either or, or both at the same time, whatever you like) or even a custom Penske or Moton with external reserviors. As long as the external dimensions, spring mount location/dimension are exactly the same as OEM, and the shaft stroke is within 1", you can do it. Springs are cheap from Mazda, it cannot hurt to replace them while you're doing the struts and mounting bushings. FYI, the rear lower shock mount can be of a spherical-bearing type to replace the factory rubber.

EDIT-- also on the springs, it's a good idea to replace them anyway-- remember back in the late 90's when guys were running '94-'96 Miata R's and were getting protested at Nationals for illegal springs (they had sagged beyond the 10mm service limit) even though they were the original owners and the springs came stock from the factory....cheap insurance, last I checked even new springs for an RX-8 were like $30 each from Mazda.

Also-- KYB models (GR-2 and AGX) are found to be stock class illegal because their spring perch locations were not the same as OEM, and compliance could not be achieved when using shims. Keep that in mind if you get a serious and protest-happy competitor.

Front sway bars only are free for replacement or removal as well, can't touch the rear unless you just replace the factory rubber pieces with new Mazda or oe-equivalent ones. Every little bit counts.

And don't use the Hawk HP+'s, waaaay too much brake lockup on street and used race rubber, found that out the hard way today :-)

Cwaters 01-16-06 08:26 AM

Thanks for the thoughts ya'll.
I don't think I'm going to get protested locally over bushings at this point but I've keep that in mind in case I'm going to other regions or in divisional competitions.

Dave, the lower rear shock just bolts to the control arm, are you talking about the bushing in the shock itself?

Looks like the springs are more like $60-70 from Mazda Motorsports. Not sure I can spend that kind of cash on the stock rate springs. If I were serious about winning, maybe.

Interesting thoughts about the HP+ Dave. I did notice I had to be careful about locking-up when I put the fronts on but I thought it would be better after I replaced the no-name rear pads with something better and got some better balance. I guess I'll try the HP+ on the rear and then go to somethign else on the front (or both) if I have problems. The pads I have on the fronts still have a LOT of life left and I'd hate to chuck-em, they bite so well.

Incedently, looking at the prices for the rear lateral links and lower control arm inner links, I don't see myself replacing thm anytime soon.... Over $300 to replace those four pieces all for some bushings and ball joints...sheesh.

CW

Black91n/a 01-16-06 05:15 PM

Don't run HP+'s on the street or at the autocross, they aren't the best choice. They're best for track days (not for tracks/cars that are hard on brakes though). The HPS would be a better choice. The HP+'s dust so much and it's bad for your wheels and hard to clean off if you leave it on for a period of time.

DamonB 01-17-06 08:48 AM

Before modding any car get the thing in good condition first. Replace all the worn suspension bushings and any shock or swaybar hardware that is worn.

Essentially the shock rule says you can run any shock you wish in a stock class but you must run stock springs and the shock must mount the spring at stock ride height.

Double check the price on the springs. If you got the price from Mazda Motorsports that was most likely for a pair, not each.


Originally Posted by Cwaters
Incedently, looking at the prices for the rear lateral links and lower control arm inner links, I don't see myself replacing thm anytime soon.... Over $300 to replace those four pieces all for some bushings and ball joints...sheesh.

CW

If they need replacing price shouldn't matter. If the car is already not put together right adding mods elsewhere won't fix that. Get the car in good shape first or you're wasting your money.

Cwaters 01-17-06 09:30 AM

Damon, I agree with you.
Thing is, I don't really know if these things need replacing or not. They seem ok but I don't really know how to tell.
Would it be nice to just replace everything and have all new? Sure.
I AM working towards replacing all the worn out bushings and such. I've almost got that done. It's some of the other stuff that I'm not sure about. Eventually it's all going to be done.

It's easy to say "Price shouldn't matter". Fact of the matter is, it does. If it didn't, I'd be racing a nice new purpose-built racecar every weekend. As it is, I'm just trying to get my RX-7 back on the road in somewhat better shape than it was when it ran last.
Unless the lateral links are bent or causing some problem that I can descern, they're probably going to stay down on the list somewhere. That's all I was saying.

Price listed on the Mazdacomp site (in my cart) for front left coil is $69.75 and the right coil is $64.65. Rears are $61.15. Unless there's something I don't know

In other news, I'm still waiting ot hear back from Koni about rebuilding these front struts. I got two emails from them about my first question and they seem to conflict with eachother. Now that I've decided to put off the coilovers another year (or more), I have some more information to put into the decision about these...

DaveTurnerMotorsports 01-17-06 12:19 PM

Konis, in the end, are cheaper to just replace with new units. My experience has seen 8-13 weeks lead time on rebuilds (depending on time of year) and cost about $105 each PLUS parts and shipping both ways.

Visit Shox.com or better yet (secret!!), AJUSA.com for cost of new Konis with free shipping....I think the choice will be clear. You can always save or sell the old ones, or keep them in rotation at the rebuild center.

I *may* have a set of stock GTUs springs ("stiff suspension") available for a song, I am waiting on wheel spacers as my AWR housings cause the spring perch to rub with the stock 16x7's and 225's.

Cwaters 01-17-06 01:59 PM

See Dave, That's the kind of experience I don't have so thanks for sharing...8 weeks is longer than I want to wait at the moment. 13 weeks and the season's well underway without me.
I was quoted something like $100 + parts and shipping but how am I supposed to know how much parts are???

My job has me working a lot of weekends and my family likes to camp so I only get so many off weekends to play "race car". Missing any more of those because my car is down for parts isn't what I'm hoping for.

Are the GTUs springs any different than the GXL springs? I know there's soft and hard suspension, Turbo (same as hard?) and 'vert...Of course, if they're any different than stock GXLs from 86, they're not legal ;) But I won't tell if you won't.

Wish I could change the topic line of this thread now that it looks like I'm staying in ES for the time being...

Cory


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