DigitalSynthesis

Sorry to cross-link like this, but I've been having a bear of a time getting my car fixed and I need to be making my final parts orders ASAP so I can get her back on the road. I posted this originally to the suspension page, but after watching it for a while (almost a full day) I've noticed maybe a handful of people even browsing that entire forum. So I'm posting a link here to humbly ask for some more info on suspension upgrades for the 'vert. Here's the link so you can reply and view the thread as it goes:

https://www.rx7club.com/showthread.p...hreadid=255882

And my original post so you know what its about:
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Hey guys, I'm seriously considering a major reworking of my S5 'verts suspension. I have been told that my springs don't need replacing unless I want to lower the car (which I don't, particularly) but the shocks, sway bars, and bushings are all original. Furthermore, the sway bars and bushings are in sucky condition (rusted to hell) and the shocks seem really soft (e.g. I can push the car with my hands -- I assume this is bad).

I've heard excellent stuff and also crappy stuff about the Tokiko Illuminas for other models of these cars, but nothing about how they work with the heavier 'verts. It seems to me the choices are as one person had in a poll, KYB AGX, Koni yellows, or Tokiko Illuminas. Please give me some insight here on what might work well for a 'vert.

Also, are any brands of sway bars significantly better than others, and is there a known good place to buy them?

One final Q: I'm looking at engine-bay strut tower and torque braces. I'm thinking the kind with the removable crossmember are most useful for fiddling with the stuff in the engine bay (which I'm sure I'll be doing on a regular basis), but I can't find any that also go to the firewall. Is the firewall a strongly recommended brace point or is that just for serious racers? My intended use for this car is street driving and autocross, and yes, I plan to get a roll bar when I start autocrossing it. Also if anyone has strong recommendations on strut braces please let me know. Its a 'vert so I don't know if I have the option of a rear strut brace with the top and all, so I think unless otherwise noted, that I'll have to stick with fronts only.

Thanks much, I'm totally new to suspension theory.

Sir Rupert Hobo

i know what you mean about the suspension forum being unpopular... nobody is even looking at my thread.

so you don't want to lower your car? hmm, well then i don't think you need the rear camber link. but your springs might be shot anyways. so if you like stock hight then get an eibach spring set. or get ground control coilovers and the people at GC can customize your spring rates/hight to whatever you want them at. i don't think you can tell any differences from a certain name brand of strut bars... infact, as soon as i get off my lazy ***, i'm gonna put that $20 one on...

www.shox.com has great prices on alot of things. check them out.

your list looks great.

DigitalSynthesis

The only problem is I have a 'vert. I can't use Eibachs. I can't use pretty much anybody's spring set. Shox.com has a set that is OK for the 'vert but it lowers the car 1.5" which is WAY too much for me. I'd be ok with the stated 0.8" of the eibach set but those are not rated for the 'vert.

I would be interested in coilovers but I don't know anything about how to spec them out, and I'd kind of like to do this quickly, e.g. have the parts in by next week sort of thing.

Thanks very much for the input... if you happen to know of anything about spring rates or how that works with the added weight of the 'vert I'd love to know. Especially if I can run coilovers.

Sir Rupert Hobo

glad i can help

well, i'm not too sure about the vert. i see you're gonna be turboing it too(added weight). i've heard of the spring issue about the verts... is it a fitment issue? i don't think it is. i could be wrong, but you are still able to use just about any spring kit you want. it's just that those are the ratings that are given to the coupes only... i see no reason why they are "outlawed" for verts.

as for spring rates and coilovers, what sort of ride are you looking for? race only, race/daily driven, mostly cruising and sometimes tracking?

do you mind the harsh ride? if you do go the coilover route then i would suggest addjustable shocks. and you would also want your rear spring rate to be softer to prevent oversteer.

DigitalSynthesis

The spring issue is apparently weight, not fitment. The 'vert bottom out normal coupe springs like nobody's business.

The type of ride I want is a tighter-than-stock sporty performance feel while still being comfortable enough for a few hour's ride around town with a girl... I did buy a 'vert for a reason. It's pretty sloppy right now, feels neither tight nor sporty although its not yet what I'd consider crappy. I'm just doing it now 'cause the car is already in pieces and its easier to do now.

I would mind a "harsh" ride very much, but I don't mind a "tight" or "firm" ride, or an otherwise moderate increase in road vibration, particularly to gain a stiffer, more stable high-speed quick turning platform. I want this baby to do well in the CSP class autoX - to show others that even a 'vert RX-7 can hold its own with the rest of its family, but I will probably only do that a few times a year and the rest of the time its just having fun.

ERAUMAZDA

Racingbeat is suppose to come out vert springs soon.

Sir Rupert Hobo

well, did you try searching for verts with different suspension setups? i'm pretty sure others have tried it. or you can call GC... they have people that know their **** around there, and ask for the rx-7 specialists that they have.. i think his name is tom. if you do get the GC setup, or any other coilovers, then i would suggest spring rates of 300~ for the front and 200~ for the rear...

to me, i don't see bottoming out as being an issue. the verts can't be THAT much heavier, right? 3000lbs or so? and it'll help to get stiffer springs.... my opinion

Sir Rupert Hobo

good news... i like RB.

always good stuff.

Trav

Something to keep in mind on those springs is that you are probably already lower than stock. In other words, the 1.5" drop listed on lowering springs, is from the stock height. With springs that old, you are not likely at original stock ride height. So my point is, don't get too frightened by a drop in ride height -- as long as it's not too drastic. I'd say 1" or less of drop and you'd probably be okay or similar to where you are now with worn out springs.

Also as far as what springs to buy, I think if you just order the Turbo springs, you'll be in good shape. The 'verts came w/ the HD suspension components (same as Turbo?). So you should order turbo model suspension parts. Someone else can probably verify this.

If you're not wanting a harsh ride, I'd probably avoid the coilovers. Everything I've heard (no personal experience) says that the coilovers (although very nice) will still be harsh on the streets. Also, I'm not sure how that would affect your autox class -- better check into that before you buy anything. You may be just fine with a good set of adjustable or even non-adjustable dampers. Obviously the adjustables will allow you to dial-in your ride -- you want soft? make it soft. You want tight (for autox), make it firm.

Lot of generalizations in my message, so not sure if that helps. I've yet to purchase my setup too, but these are the types of things you'll want to think about.

hope that helps a little bit...

vaughnc

Didn't read all the replies, but Mazdatrix has the OEM convertible specific springs for cheap. Tokico's are good and I think that's what originally came on the car (could be wrong). They work with coilovers as well if you want to toss the OEM type spring setup.

RacingBeat will have their vert specific aftermarket springs available Q1 2004 and you can buy those through Mazdatrix or fc3s.org as well.

Besides some nice & cheap polyurethane bushings, be sure you buy the toe-eliminator bushings from Mazdatrix to replace your DTSS setup (unless you want to pay $350+ for Mazda's DTSS hub). Also your swaybar end links & subframe end links are probably shot and need replacement. They aren't cheap , but are worth it. Mazdatrix say's don't put their "solid" end links on as they for racing only and will introduce strong vibrations & noise. So go with OEM.

Also check your subframe-body link's pillow ***** and see if their shot. They should not move at ALL, so if their loose their shot.

BTW I've heard you can get away with using Series IV end links which have replaceable (not OEM) bushings instead of pillow *****, but you can only use those on the rears.

Hope this helps.

DigitalSynthesis

Well, my autocross class is already seriously forked over b/c of the engine swap so I seriously doubt that coilovers will screw me any further. heh... anyway, I did end up going GC coilovers, from shox.com, and the guy there seemed pretty familiar with the RX-7 platform and said that yes, it will be stiffer, but it won't be unbearable for moderate highway trips and all. Of course around town nobody cares what the ride quality is like anyway... people buy jeeps and drive them cross country.

I decided on Koni Sport struts, GC coilovers, Energy Suspension bushing set, Racing Beat sway bars, and the jury (as I posted in the other thread) is out on the front strut tower brace -- Racing Beat does NOT fit the convertible , so I've got to choose either no engine torque brace or the madzatrix SUPER EXPENSIVE three-point thing, which after purchasing the coilovers I don't have money for. If anybody has any good suggestions about the strut brace/torque brace, I'd be willing to listen.

I also purchased the competition transmission and engine mounts to go with this. Yeah... I'll feel everything, but I want the stiffer rubber so hopefully it will last longer.

DigitalSynthesis

Vaughnc, thanks for that wisdom there. I was about to buy those same solid end links. I will have to check those pillow ball joints. I noticed you did a write-up on those and will definitely refer to it at that point.

Drop Top 13B

I have an '88 Vert. I installed the Mazdatrix 5-point strut/engine brace on my car, and damn, what a difference. I love it. Highly recommended. Given that one of the major structural pieces is missing in a vert(ie the roof), the front brace stiffens things up quite well. So well in fact, that the rear end then felt like wet noodles by comparison. This necessitates a rear strut bar or rollbar to stiffen up the back. The 4-point rear strut bar from CP racing out of Canada does fit the verts, you just can't have a spare tire anymore. I have the CP rear strut bar and a custom 4-point rollbar in mine. It now feel stiffer than the last coupe I drove. The torque strut from the bar to the engine really helped with engine shutter, vibration, throttle response and launching too. Yes it is a little mo $$$, but in my opinion, worth every cent on a vert. The install, unlike a traditional bar, will take longer than 20 minutes, but can be done in an evening. If you own a convertible, save your cash and get the mazdatrix 5-point firewall/engine/strut brace you will thank me later.

Drop Top 13B

btw, how did you, or where did get blacklit UV Gauge Needles. I would like to know.

Lodivigo

Ditto, got any pics?

vaughnc

SURPRISE!!! the convertible has an OEM rear strut bar. That's ONE of the reasons the convertible feels much more planted and less sedan like than the NAs & TII.

DigitalSynthesis

Hehe... coming shortly. Its pretty damn killer. Info and a writeup may be forthcoming. We'll see if I have time. In the meantime, search for ultraviolet and gauge and look for a post by node.

sub9lulu

iTrader: (7)

hey
dont forget the S4 suspension is stiffer than the S5
you might want to just switch the suspension to the S4, get some S4 oem ones, or find someone's S4 vert and drive it feel the difference

Drop Top 13B

Ok, you have actually driven or ridden in a convertible right? More planted, and less sedan like? Um, not mine. At least it didn't start out that way. There was enough rear chassis shutter and shake that it felt like it would spin out during a turn if you hit even a small bump. Maybe there was something wrong with mine, but I would describe the stock handling limits as nothing short of SCARY. As for the OEM rear strut brace, either you are refering to that thin piece of tin seperating the trunk from the interior, or mine didn't have one. That thin piece of tin is there for no other reason that to attach the Trunk trim to.

DigitalSynthesis

Um, Vaughnc owns a 'vert, or maybe two, last time I checked. Mine handles very nicely, quite firm, and "planted". Your 'vert may have a busted rear anti-sway bar or something. And, no, he's right, the 'vert does have a sort of strut bar. Although its not at the very top the rear suspension tower is, to my knowlege, reinforced significantly more than the coupes. I haven't ripped plates off to check but I think I saw it in the diagrams. I'll check again shortly.

CarMc1

I hope it isn't too late to join this discussion because I have a question regarding the S5 vert springs. I'm looking to lower mine by no more than 1" and have had the same problems finding springs rated for the verts. If R.B. is going to make the springs that will be great, but since the rear suspension is only set up to adjust for toe, what can be done to correct for the increase in neg. camber?

Thanks for your thoughts. Oh, one more thing, my 91 vert is very solid. I've driven many, many, too many to count 2nd gen. cars in all configurations and I find the verts to be less flexing for the most part.

DigitalSynthesis

CarMc1, no problem. I'm personally quite fond of people bringing up old but worthy threads for modernization. Sort of the point behind a thread, IMO.

For your negative camber setups (which I am also interested in) there are a few solutions. Remember that like alcohol and controlled substances, too much negative camber is a bad thing. Hehe... but seriously, since we have a problem getting ANY negative camber once we mod our suspensions, there are two main methods to adjust for that.

1. The Racing Beat Camber Bar. This is a bar which replaces the "sublink" in the rear suspension (the fixed vertical connector which attaches at the left of the differential to the subframe itself and connects to the chassis just forward of the gas tank). This can reduce camber evenly to both wheels, and can pull about 0.7 deg. total. If that's not enough there is....

2. The mazdatrix negative camber adjusters. These aren't cheap, but they allow individual camber adjustment on each wheel, and can dial in more than a full degree of ADDITIONAL negative camber than just the RB camber bar alone. If you find the RB bar to be not enough, add these and you'll be sitting pretty.

I didn't want to wait for the RB springs, so I went ahead and bought Ground Control coilovers to go with my nice new Koni Yellows. Of course, nothing is ON the car yet, as I'm still cleaning and painting the underside and engine bay in my free time. But I hope to get the suspension and underbody done by this weekend, which will leave me the following week or so to get my spiffy new turbo engine set up nicely. Its been sitting for over a month now waiting to be installed. I can't wait.