First, I would like to preface that I know "seat time" is the way spend money, but I am in a situation where some components of my car need to be replaced/upgraded before next season anyway.

With that said, I am considering a few options for suspension upgrades on my 91 CRX, after I obtained some Ksport full coilovers at the junkyard for only $80(!). In keeping with the suspension upgrade path, I want to fix a few problems I know already exist. I know for a fact that my OEM rear trailing arm bushings are in pieces, and my OEM front upper ball joints are toast.

My thought automatically was to go with PCI trailing arm bearings, and SPM upper control arms, as a nice upgrade to go with the ksports.

Some things am waffling on are the longevity of the PCI bearings in a street driven car. To be fair, I pretty much only drive the car to and from Autocross races where I race in the SMF class, and only when the weather is nice, if i can help it. I am also waffling on the front upper control arms, as I will obviously get some negative camber automatically from the ksports, so there really isn't so much of a reason for me to get the upper control arms unless i want to dial out that camber or decrease it further (I don't think either will make much difference at this point).

The main hitch in all this is that whatever I do, i would like to keep it SMF legal, which I believe both upgrades are.

Alternative considerations for upgrades are a full race traction bar(though radiator situation may preclude me from a second option) and the 22 or 24(?)mm ASR rear sway bar and subframe brace, with just OEM replacements of the trailing arm bushings and the front upper ball joints.

Last, I am running SMF on street tires, so i have considered picking up some slightly used dot-r or full slicks instead of street tires. I can likely only afford used, as new may be out of my price range for hoosiers, at least.

I only have enough for 2 of the 5 upgrades listed, so I need to decide which upgrades will be the biggest benefit, given that I am likely only going to be able to afford these upgrades for all of 2012.

I am happy to hear commentary, criticism, completely off the wall suggestions, or anything else..

TL;DR: Most recommended upgrade option (pick 2), and why, to remain legal in a 1991 CRX running SMF autocross:

1. PCI trailing arm bearings
2. Special Project motorsports front upper control arms
3. ASR rear sway bar and subframe brace
4. gently used hoosiers A6 or the like as a set of 4

>OR<
Full race traction bar and radiator by itself

 

leave the traction bar out of the equation.
waste of money and added weight.

 

man, added weight. I didn't know that. Thanks for the insight.

 

sway bar and tires. Get that rear end rotating much easier and still stay stuck to the pavement.

 

SMF, dude, sky is the limit. things needed to know though.

engine swap?
Si, DX, HF?
what does the car have already? setup?

it is possible to get 6th place at nationals with a STS crx in SMF, ask my buddy mike with the SSC silver Crx Si, with the only major upgrade being he ran 13x8 rims with hoosiers.


if you only have enough money for two, go with the swaybar/tire combo, and if you're really tight on budget, get the R6 instead. once you get the R6's up to temp, they are just as sticky as the A6(another autox buddy runs them). you'll get more runs/heat cycles out of them then the A6. this is for a budget standpoint.

 

Proper traction bar such as Full-Race design are better than stock.

http://www.full-race.com/store/tract...tion-bars.html

 

Just look at that monstrosity..... what a waste of metal.

 

Have you ever driven a car with traction bar installed? I don't think you have clue what you're talking about when it comes to weight. In CRX/DA you replace the stock piece with these. The old stock unit is usually worn out and have plays... you save weight.



See the heavy stock Honda design?

This is a home made one from Montana CRX thread. I love the bends they made... sweet.

 

Yep... driven one and didnt feel any benefit...
Ripped that puppy straight out and never looked back
BTW I dont drive my EG on the street.
There are no green light to green light runs for me.
Strictly track use only.
Maybe its you who doesnt have a clue... ?
Changed out my compliance bushings and all was right with the world.
Simple, cheap and worthy investment. Race proven.
Check out this thread..
https://honda-tech.com/forums/showth...=traction+bars

Not a necessity on a road race car.
Nor will that low hanging piece of crap allow me to use my splitter.

 

lol

 

Maybe you can't read. The OP said he has a CRX... and in my post I was talking about DA/EF chassis.

 

No I can read just fine there....
Traction bars arent necessary for road racing.
Drag cars sure... You are only going in a straight line.
The excess binding it causes when you turn makes the car steer like a pig IMO.
But hey if you like it... and its your preference not to mention its sweet looking when you look at it... knock yourself out.
You are entitled to your .02

I on the other hand prefer my car to turn and rotate when on track.
I also like using a splitter, which if a traction bar was a necessity Id have to modify it to mount my splitter brackets, and add extra weight to the car.

 

While traction bars may not be necessary for racing, they do have some advantages on the CRX/EF chassis especially for road or drag racing. First of all, the factory delivered EF/ED chassis uses a radius rod on each side that pivot on individual front cross beam bosses. At each boss, the radius rod feeds through a split rubber bushing that helps isolate the noise, vibration, harshness (NVH) from the chassis. These rubber busings were designed to provide compliance to reduce unwanted NVH for the car's intended use which didn't include racing and track duty. Unfortunately, especially for cars using R-comp tires, the rubber bushings deform significantly under acceleration and deceleration causing the radius rod (RR) to move fore or aft at the bushing. This RR movement also moves the LCA forward under acceleration and rearward during braking. The LCA movement also tire toe change (toe-out under braking and toe-in under acceleration). If one front tire has more grip than the other, the result will be that the bushing on the side with more traction will deform more than the other side. This will cause a net toe change between the two sides and thus this will cause a steering effect - I guess you can call it accel-steer or decel-steer. The more nose weight you have and/or the stickier the tires will exacerbate this bushing deformation and subsequent toe change.

With a traction bar and suitably sized high-strength rod-ends on both ends of the radius rod, you can virtually eliminate this radius rod compliance thus elimination any accel or decel-steer. Also, before these traction bars came out, Progress used to sell a spherical bearing kit that replaces the factory rubber bushings. I've used this on my CRX since 2002 and it works great.

The traction bar doesn't cause binding, at least not on the CRX/EF, since it still allows the suspension one degree of freedom if you use a spherical bearing on the inner LCA pivot. If you use the factory rubber or worse a urethane inner pivot bushing then there will be some slight (with rubber) to more pronounced (urethane) binding due to the radius rod forcing the LCA to move in slightly fore-aft plane.

Needless to say, but the traction bars will probably increase NVH for street driving but on the track-only or race car it isn't a problem. Also, traction bars are not allowed in many or maybe most racing classes.

 

[ Also, traction bars are not allowed in many or maybe most racing classes.[/QUOTE]

Another good reason not to use them.


Thanks Johnny you always explain things sooo well, and then I have to start doing more research on what the hell you are saying.

 

My car is running a B18b and an LS transmission. As far as already set up, I have a ACT stage 2 sprung clutch and 8lb flywheel, dynomax superturbo exhaust with test pipe, AEM cold air intake, chipped PR4 ecu, and that's about it, unfortunately. The Ksports are the next upgrade that are ready to go on, and will be running eibach 550lb springs in front and 300ish in back.

Thanks for the insight on tires, a6 vs r6. I have read about that, but its nice to hear my assumptions confirmed.

Man, this is good info also.. I do get some wheel hop when leaving the line in Autox, and I figured my only hope of fixing that was the full-race or similar bar.. but it sounds like those bearings might be a great option too when I am ready to tackle that problem, if i can still find them.

My interpretation of the rules for suspension in SMF is the sky is the limit, as long as the stock mounting points are not moved, but I am glad I asked, because I would rather there be no question about legality at this point. In terms of legality, i suppose the way the traction bar mounts up, it probably doesn't use quite all the mounting points, which is where the violation comes into play?

I think several people have said this now, and I have read a lot about the rear sway bar being a really effective upgrade, along with a few threads about CRX subframe tearing that scared the hell out of me, so tires and the sway bar are going to be my path forward.

 

Fix your trailing arm bushings before you do anything. Even if you just put stock ones in. If your front ball joints are really bad I would replace them as well. Before you spend a lot of money on upgrades you should fix the problems you already have.

I would recommend the above with Honda parts, sway bar, tires and an alignment.

 

I'm agree about the traction bar. You're not drag racing. Why spend money for no noticeable benefit?

Johnny Mac and Dirty are both right.

Don't spend $400 on a low hanging, heavier traction bar that could make the car illegal in many classes when you can spend $180 on the pimpy spherical bushings Johnny was talking about:

http://www.progressauto.com/products/productID/626




My recommendation for your upgrades:

TIRES. Since that actually touches the ground, it's the most important!
and
Probably the upper control arms as tuning camber can be helpful. You can always get the car to rotate at an AutoX with Toe. Not the best way to skin that cat but until you get your car more sorted it works.


I loathe Autox'ing so maybe I'm not the best person for AutoX setup advice

 

And if you are willing to spend just a little more than the $180 above you can go with a front radius bearing setup that might outlast your car.

Progress uses what they call a COM10-AB but is actually the Aurora part COM10-T. The COM-10T has a maximum axial load rating of about 4256 lbs and uses an inexpensive PTFE liner. The NHBB (New Hampshire Ball Bearing) ABWT10 bearing that we use in this application has a maximum axial load rating of 9,195 lbs, uses an extremely high end PTFE liner and is MIL-SPEC rated.

Whatever you do, skip the traction bar IMO.

http://kingpinmachine.com/store/prod...-rod-bearings/

 

This presents the one area where the Progress Group's CRX/EF radius rod spherical design isn't ideal. In their kit, the load acting on spherical bearing is essentially a thrust load. This means the radius rod's load always acts nearly parallel to the spherical bearing's outer race cylindrical centerline. However, spherical bearings are designed to handle radial loads, but not thrust loads. As a matter of fact, the thrust capacity is not published for most spherical bearings since the bearing manufacturers assume people will not be using them for any thrust loads.

In addition, in a race car where most or all of the rubber bushings in the suspension system have been replaced with spherical bearings, the loads acting on the radius rod sphericals are much higher. Needless to say, but after a two seasons or so of racing miles, the spherical bearings in the Progress Group kit may need to be replaced.

So why did Progress have to design their kit this way? The answer is that Honda's front crossmember's front radius-rod pivot boss design doesn't lend itself to easily using a spherical bearing in radial loading. Instead, as one can see from the photo of the parts making up Progress's kit, installing a spherical that opposes thrust loads is far easier. And despite the increased maintenance of bearing replacement, the Progress kit or the kit that Chris is discussing is still a very worthwhile performance modification.

On the other hand, the traction-bar's rod-end bearings are loaded radially like they're supposed to be. Thus, the rod ends will last longer for a given bearing size when compared to the Progress Group's design. So while these traction bars don't have a lot of fans here, I can say that their basic design is proper.

 

Excellent explanation as always Johnny. It should be noted that manufacturer's like Progress and myself only make the application as is for class legality. Nearly all of my customers are SCCA IT and/or NASA HC/PT racers. The ruleset only allows replacing the front radius rod rubber bushing with alternate materials including a spherical. However, redesigning would not be allowed since the stock radius rod must be used as is. The same problem occurs when running sphericals in the upper shock mounts. All of the force is essentially trying to push the ball out of the race and this axial load is what wears the bearings prematurely. That is why I chose to use such a high end and unfortunately expensive bearing in those applications. What appears to be overkill in terms of the 9,000 lb+ axial load rating is actually needed to ensure long life.

P.S. I must admit I thought traction bars were primarily a better fit for drag cars but I can see the benefit particularly in this radius rod application. Thanks for the info. As always, the first step is figuring out what class you want to run and then build your car accordingly.

 

make sure the ksport shocks can handle that spring load.

and if you're worried about subframe tear out, get a ST rear sway bar. it's mounts to the stock location for crx/civic of that year.


and don't forget, sky is the limit for suspension, and engine. but don't forget you might get a weight penalty for some engine mods. for interior, everything must be in the car. meaning no gutted interior, and must have all plastic pieces in the back

 

Would be interesting to see the total weight of this unit verus the OE sub and rods.

 

Yah there's a guy here in so cal, Darin of West End Alignment. And he has a Full-Race Traction Bar on his Time Attack EF Civic. And definitely notices a difference. I don't know of any race alignment shops in Tracy or nearby. But West End's the place here in socal.

Darin has an over abundance of suspension knowledge, so I'll take his word over yours. No Offense to you, you just seem hostile about it.

 

You can use them in TA but not in HC.

Most wheel to wheel sanctioning bodies dont allow them.
The cost vs benefit... puts it square in the "dont bother catagory"

 

I can understand that but when your pushing for every second it will matter, no matter the cost. And it looks cool. You forget that, which is very important. Lol