cheap suspension upgrade
 

i really like the thread about 1st gen cheap upgrades. i would like to see a similar thread devoted to suspension upgrades. i don't have a large budget and don't know the best upgrades to do. i drive my 84 gs almost everyday. i don't want a race car but comfort isn't a big concern. besides, we don't have rx-7's for comfort do we? anyway, i don't know a whole lot about the technicalities of suspension upgrades. i know i want my car lower and handle better. so far, all i have done to the suspension is change the rear from a gsl so now i have rear disk brakes. i know i need lowering springs but i don't know about bushings, or if i need strut bars or sway bars. after 210,000 miles, i'm sure i need new shocks. what is the order that you would make these upgrades, or is it best to save up and do it all at once? pleae help with any info you can give. thanks.

There's no real cheap way to do suspension, but here's probably the best affordable setup for the street.

Tockico HP Shocks
Racing Beat or Eibach Springs
Racing beat front sway bar
Stock rear sway bar
Any strut tower bar

I hope to see how well hockey pucks get the front end off the ground. :)

Talk about an upgrade! Raise the front roll center, meaning less roll in the front which meeeans should be easier to drive hard into corners (more understeer) and reduced body roll would leave more suspension travel for soaking up bumps in addition to the fact that there'd be an inch or so more jounce travel in the first place. Then the stock front struts won't be so absurdly stiff and take forever to take a set, since there'd be less body roll. And the steady-state understeer might actually be *reduced* because of no longer driving on the bumpstop on the outside in corners.

Already have what I need to raise the rear an inch or so. But the front is just as important if not more important.

*Poof* Consider it done. A new sticky. All I ask of you guys is that you state the application of any mod you suggest. Like Street, Autox, Road race, Drag race, Circle track, or combinations thereof. :beerchug: :)

How about some more info on raising the front roll center, I am definately interested in this.

uhhhhh, why would you want to RAISE the car? having the weight closer to the ground would decrease body roll.

^that is what i thought? if you raise the roll center, wont your car have MORE body rollif your really worried about travel and want to lower your car, cheap isnt really the way to go, cause you can get the racing beat front lowering kit, wich will lower and ad about an inch of travel(or give the same travel as b4 since its lowered). for me, a cheap upgrade is Tokico HP shocks with one coil cut from the springs(preferably GSL-SE springs.)but, alot might disagree, and i do also, but the ride isnt all that bad...

Raising the roll center does not mean raising the car necessarily.

the item i got the most feel outof when i installed it on my cr was a 3 way brace...aka firewall/strut tower brace. the unit i had was a r.e. old school deal it was acc.5 peices bolted together. 2 plates that went on the strut tops(4 bolts) a bar to conect the 2 and then a shorter bar from the back to the firewall. man did this improve the feel and stiffness of the car. i did this on a street car i would take to road courses from time to time... i also had koni ajustable strut/shocks ebach springs i redid the front end in urathane. s.s. brake lines sloted rotors and carbon kevlar street pads.... on a 81 gsl.... the 1.5" lowering springs really raised my car almost an inch... but im sure the old stuff was stock @180k.... DAM i miss the beast :(

Raising the roll center of the steering changes the front suspension geometry. Which in turn allows you to be more aggressive on your turn into the corners. I am just not sure how to make that happen on the RX-7.

maybe when i said "cheap" that wasn't the best word. maybe i should have come up with a more appropriate word. i know it would be real easy to drop $1000 on suspension alone. i would like to do that but realistically, i will have to do it $200-300 at a time. does anyone have any suggestions on what to start out with and what could wait until the next $200 is available? thanks

springs... get some springs , thats probably the easiest thing ... depending on the state of your shocks , blown or not , if theyre stock , they wont last too long in a lowered car as they are designed to operate with a longer stroke , as oppose to short shocks(aftermarket) which are meant to operate based on a shorter stroke , the other thing would be a strut tower brace? ( if we can get em ) i dunno , im old school honda so the rxthing is fairly new to me ......cheers

Pete, you planning on using hockey pucks as spacers for the struts?

VIRXER- a front strut tower brace is a good cheap upgrade for sure. There are a few out there for our cars.

And there always http://www.pbandjracing.com/ in the tech section . ;)

in order for suspension...i would get shocks...then springs...then strut brace...then full urathane...and decide after.

IMHO for street go with:

Koni Adjustable in the front (real Cheap at classicgarage.com)
Racing beat front and rear springs
Some Regular performance stock replacement rear shocks like Tokico HP or Koni Non-adjustables
CP racing Strut tower bar

Performance street: (all of the above with)

Camber plates
Adjustable rear shocks
Bushing kit

In my opinion coil-overs are not realy that important if you will be driving on the street alot. it is nice to beable to controle ride hight tho.

my car on coil-overs is kinda a pain on the street 350 springs in the front and about 75%-80% full stiffness of the front struts dont help much, with a "smooth" ride

How much is a uruthane bushing kit? For the front.

www.racingbeat.com
racing beat springs front = $100 (pair)
racing beat springs rear = $84 (pair)
racingbeat camberplates = $305
racing beat strut tower bar = $285
racing beat swaybar front = $121
racingbeat swaybar rear = $199

CPracing.ca
CPracing strut bar = $99 (regular)
CPracing Strut bar = $115 (triagulated connect to
firewall)

www.classicgarage.com
koni adjustable shocks front 79-80 = $60
koni adjustable shocks front 81-85 = $100
koni adjustable shocks rear 97-85 = $188

www.p-s-t.com
Bushing kit = $159

www.ground-control.com
ground controle coil overs = $195 (requires strut housing to be modified)
Tokico HP shocks front = $120 (pair)
Tokico "Illumina 5" front = 248 (pair)
Tokico HP shocks Rear = $80 (pair)
Tokico “Illumina 5” Rear = $216 (pair)
ground controle camberplates = $265

Just a thought- should rim and (especially) tire recommendations be included? I know there is a poll somewhere for the best rim and tire size- maybe that should be moved below this?
I realize rims are generally purchased for style and personal flair but theres a number of tires available with various performance charactaristics. I'm sure some of you folks running autocross/racing have preferences or valid opinions.

Thanks.

Body roll has little to do with the height of the car. In any event, body roll is not a bad thing *unless you're running out of suspension travel*.

You're confusing weight transfer with body roll.

Weight transfer is directly related to CG vs. track width.

Body roll is the CG's mass, divided by the distance from the CG to the roll center, versus the roll stiffness of the suspension.

For most cars, when you lower the front, the roll center drops faster than the CG does. (Fox-body Mustangs are famous for this) So what happens is the roll center is further away from the CG, so the CG has more leverage against the suspension, so there is MORE roll. Even though there is less weight transfer due to the CG being lower.

So not only does the body roll more when you lower, but there is less suspension travel to take up the bumps. So you wind up having front springs at least twice as stiff as stock.

G-Force Racing will sell you "turn in spacer". These exploit a weirdness of the RX-7 front suspension, which is that the knuckle is two-piece. The spacers move the ball joint lower, raising the roll center, decreasing body roll for the same suspension roll stiffness.

However, I don't plan on running racing springs, I like having ground clearance and suspension travel, so why not get the benefits of the ball joint spacers by simply raising the suspension up? Gives me the best of all worlds for what I am concerned with, which is REAL WORLD speed. Meaning driving over roads that have actual, you know, BUMPS in them. Nothing worse than railing a corner at 60mph and coming across some cross-road frost heaves. IF you have no suspension travel that is! But with a tad less body roll and a lot more suspension compression travel, bumps would be No Worries since there'd be plenty of travel left to soak up the bumps even at high G cornering. And plus, no more listening in anguish as the crossmember and exhaust bash the ground over the really fun roads. I drive 45mph down roads that the simpering fools pick down at 15mph in their Grand Cherokees.

For the rear it's the same thing.... except it's "why should I spend big bucks on a Panhard rod setup to get my roll center lower down (needed for different reasons than raising it in the front), when I can just raise the CG up away from the roll center in the Watts?" Again, win-win-win situation. More predictable handling, more suspension travel for that Real-World Speed, and costs a ton less than The Accepted Way of Doing Things.

BTW - A regulation hockey puck is *just* the right diameter to fit inside the FB front lower spring pocket. Just need to holesaw out the center, make a slice to allow it to fit the spring pocket, and maybe a hoseclamp around the mess to prevent it from spreading. Times two for a roughly 1.5-2" additional ride height, which ain't much considering with stock springs there's only about an INCH of compression travel with the stock sagged springs. But that's right in the middle of the strut's stroke, and rebound travel is as important as compression.

hey thankz for the info on the shocks...(81 rex ...so sorry that you live in cali with the emmisions and all...don't they have a law of 20 years considered historic (no emission)..? i just bought my 8th rx my second se...loving life...

the no emission law only effects cars that were built before 1973...

so yea need to get smoged... but lets just say there is a place, run by a guy, that smogs a car, that passes no matter what... ;)

i know what you mean 81rex. when i was a kid i lived in california. my parents had an old suburban that would pass for emissions for $50.

Hiya Rx lovers,

I have owned my 1st gen '79 for 6 years and I'm now undergoing a full suspension rebuild along with a friend of mine who recently bought a basic but straight 1st gen shell. This weekend we'll attempt to make some front adjustable camber plates with fixed castor probably like riffraff's 4-sale sev (which looks very cool). I have seen some good pix from the TEIN website detailing the pillow-ball mount http://www.tein.co.jp/pumnte.html. Import parts are pricey in NZ and custom fabrication is popular here - I will make strut-tops for my 323 (GLC) too. We will go for a DIY fully-adj kit for ride height - I'm looking at a full kit for around US$420. That should sort it. I agree with the stock rear swaybar - I think the early cars like mine have the largest 1st gen one if you want a really stiff setup. I will try and get a whiteline adjustable front swaybar www.whiteline.com.au
Get sonme sticky tyres too (be sure to fit decent wheel studs with aftermarket wheels too). I have tried Toyo proxes FZ4's on my rwd GLC (5-door hatch) (P215/50/13) and they are a cool non-race tyre with great all-weather grip. I will use these on the sev for a while once I've completed the build-up on my 12A bridgeport, then probably get Toyo ra1's.
I plan on running 225/50/14 RA1's on the glc for a while too - it has stock 1st gen front struts and brakes (bolt-in but slight +ve camb.). The glc has some old style KYB gas-a-just (black) rear shocks that are great (bought 2nd hand for ~US$20) these are very stiff and short so I can run cut rear oem springs and have great rear suspension. Soon the front to match. I will try to replicate a rx-7 setup on the glc front (I'll add an rx style swaybar and tension rods) and have really low aftermarket springs. Any questions on my setup drop an email my way.

Basically I won't go over the top but it won't essentially be 'cheap'. I'd say go for awesome tyres but with huge grip (if you choose wide toyo ra1's) make sure you have fresh gear oil in the trans and diff - expect the driveline to be under greater load.

This is my first post, yay. I want to hit 100 soon to get a custom avatar of my sev. My next few posts will probably be short.

Alright, Im working on my SE, and i am currently making a list of what i need to get to get the whole project done.. (damn i need money).

I have a pair of KYB's for the back that i got when i bought a car... but i don't know if i will use them.

I guess my main question is what are the main differences between the KONI's at classic garage, or the Tokico HPs and Illuminias?

I have a set of the konis on my GSL, and am happy with them, but i was wondering if the tokico's are any better.

BTW, probably going with racing beat springs.

i like where tom was going. i have thought a lot about wheel and tire size. the poll on best looking wheels and size but i haven't seen a whole lot about tire size. i like the 16's and i heard the biggest you can go in the front is 16x7's with 205 tires. does anyone know how big you can go in the rear. i saw somebody with 16x8's in the rear but i don't know about the tire size. does anyone know how big you can go in the rear? thanks.

i like where tom was going. i have thought a lot about wheel and tire size. the poll on best looking wheels and size but i haven't seen a whole lot about tire size. i like the 16's and i heard the biggest you can go in the front is 16x7's with 205 tires. does anyone know how big you can go in the rear. i saw somebody with 16x8's in the rear but i don't know about the tire size. does anyone know how big you can go in the rear? thanks.

Tell me more O mighty one. Are you talking about slipping the puck under the bottom of the spring, or somewhere else. I'm interested in trying this as it seems like a cheap project to take on, with many benefits. Times two for a roughly 1.5-2" additional ride height That confused me, are you talking about using two puck per side? I wasn't quite sure. Thanks for the ideas.

George

^^^ That's me ^^^ Room mate left his account logged in, damn FC guys, lol.

The suspension is in.

And it is Good.

Two hockey pucks per side in the front, one roughly inch tall coil-saver mounted *over* the rear springs. Goodly amount of ride height increase - now there is three inches of compression travel from static ride height in the front.

Working on a more complete write-up as I continue testing the car. Let's just say for now that I was right about everything. :)

Yes a write up and or pics would be nice. IS there any info available now anywhere on the hockey puck setup? AM gettin close to puttin in my new struts.

Tiers

Just in this thread, and a similar thread on Mazspeed.

There's nothing to the hockey pucks. Buy hockey pucks, run through 'em with a 1 7/8" hole saw (I used a 1 3/4 since that's the OD of the strut, but that turned out to be JUST a little too small), slice through it so it can twist under the bottom coil. If you go with two under each front spring then you'll want to wrap a hose clamp around the upper puck to make sure it doesn't squeeze out.

Note that in either event, you will want some way of raising the rear as well, to get the full effect.

Car looks *gooood* now, BTW. I hate the lowrider look - it has no function for a street car, and I can't see any form in something that has no function.

I can speak very clearly about the most improved handling mod I found w/ my Miata. Jackson Racing sways. Flattened turns like you can’t believe! Did shocks. Springs & sways to the 7 at the same time so can’t differentiate what was the most valuable component.

Hmmm, very interesting.

I think I might start off with one puck and go from there. As it stands the rear has double the gap from the front (I'll actually measure it properly one day), so I'd like to balance it out. I remember reading on ausrotary that the 1st gen is one of those weird cars that likes the rear slighty lower than the front for best handling, like 10mm.

Well the price is right, I think I'm going to fiddle with this once I find my spring compressors.

That sounds really interesting. I'm seriously considering getting rid of the tociko springs in my car. I don't like the 'slammed' look and the kidney pounding ride. So this set up would work with say- RB springs (which are a little softer than Tociko's) and basically orient the height back to stock? Wondering aloud here- but what about running new stock springs, tociko illimuna's and stiffer front sway bar, stock or adjustable rear swaybar..in lieu of hockey pucks??..) I like a car that handles but not punishes :)

On the subject of hockey pucks...why not just make yourself some turn-in-spacers??? I could see it if you off road ralley race or something but I think you guys are all blacktop racers and I don't understand the benifit of raising your cars COG and making it less aerodinamic.

Also, be very carefull and check them constantly. Hockey pucks are well known for being used as hillbilly body lifts in 4x4s. In this aplication it is bolted tight, doesn't get the extreme cyclic loads that it would in your suspension, only supports the cab not the hole rig, using 10 - 16 mounting points vs. just 4 with your aplication.

Check them constantly, eventualy they always crack and begin to crumble. If one comes out on you while you are driving down the road heaven help you...and the other people on the road. A large band clamp snuged around the outside of the puck will buy you some time...keeping the large chunks together untill you notice the broken puck.

Coldy 13: WORD.
RB springs, Tokico Hp shocks, RB sway.

Look at it this way - It's cheaper than buying new coilover springs, but it's a great way to see how altering the roll couple affects handling.

Plus it is SO nice to have suspension travel. Truly it is.

I'll probably end up buying some 14" long 110 pound 2.5" springs and using them. It appears that with two pucks, the coils in the front can bind at full compression. Need to fix that. While I have it apart again, I can install some camber plates, because while the handling is greatly improved, the understeer is a bit much at times. (Probably due to all the positive camber)

I *could* reinstall the rear swaybar... but that is merely reducing the rear grip to benefit the front. I like being able to accelerate out of corners.

I'm not worried about longevity, in other words. They *do* seem to be holding up just fine. However, I think I broke another rear suspension link, and the ball joints are now loose too... the hockey pucks might outlast the rest of the suspension! *grin*

The coils *are* binding.

https://www.rx7club.com/attachment.p...postid=2812500

Note the rub marks on the coil the yardstick is pointing at. The coils are binding when the suspension bottoms (yes it's still bottoming even with 2" of lift) and when that happens the smaller diameter coil is going up *inside* the other coils. Mega badness.

First clue was that the ride height has dropped 3/4" in the front over the past roughly 1500-2000mi. That should not happen with used (pre-set) springs. Then I looked and saw the problem.

So BE CAREFUL. Make sure the springs can't coil bind! One way is to use a bigger bumpstop... but while that gives you the geometry benefits, it doesn't do anything about suspension travel. (Again, note that it's STILL bottoming out!) Could use less spacer... but then you lose both travel *and* geometry. The real solution is stiffer and/or longer springs. I'd like to try both a 12" long 150lb spring, and a 14" long 110lb spring. But that costs money, and a stiffer spring would require different shock valving.

Interesting
 

Carful with the big wheels. This car was designed for 13 inch wheels as far as geometry, ride height, clearance and brakes.

Think of the wheels as flywheels, because they are. Four flywheels to be exact. When you go up in diameter you place most of the mass at a larger diameter and the rotational momentum of the wheel goes up by the square of the difference. It takes more to accelerate and more to brake. If the tire OD is bigger than stock it also reduces the leverage on the brakes. Do that and forget about much lowering, because it won't fit under the wheel wells, and will look like a 4 foot man with size 10 shoes. So be smart and stick with stock tire OD or less and the lightest wheels you can, whatever the OD.

When the front roll center goes close to ground, meaning the lower control arm becomes level, it also becomes unstable and moves as much as five feet laterally per degree of roll. Think of the roll center as a teeter totter, and the roll center is the pivot between the springs and the wheel. Not only does a lower car lose roll stiffness, but the car can become quirky if you go too far.

Going stiffer also needs more damping. A lot more. 500 lb springs can feel really glued to the road when the proper damping is used. It is the lack of suitable damping from a warmed-over street shock originally designed to produce 15% of critical that is usually the problem with going very stiff. All the shocks but the double adjustable race Konis are no good over 300 lb. or so.

Look at my products at gforceengineering.net. Every one of these was designed to solve a problem with the lowered suspension. The bullets tell the story of why.

Expensive, yes. But you get what you pay for. Suspensions are very complex.
If you are not bridge designer and don't know what happens when you change the bridge supports, I woudn't be driving over that bridge. Your car may feel OK for street driving, but just wait until you have to make an emergency maneuver!! This car is known for getting ugly real fast even when stock. Without a good understanding of what needs to be done to correct the already screwey geomentry, it gets worse the lower you get.

Jim

Welcome to the forum, Jim. Your reputation preceeds you.

Looking forward to any wisdom you might want to share with us.

RXDad

Thanks
 

Well, thank you very much, RXDad. Hope most of the comments are good. It's the main reason I do this.

Jim