Since all the coilover posts magically disappeared i will ask again. Does anybody know if a coilover setup would be good for AutoX. I am looking to lighten the load and go with a coilover tubular k-member also. All the info i have found is that coilovers are for drag racing.

Fabbing and welding is no problem but i don't want to competely engineer a setup. Can anybody help me out.

 

I autocross and I have wonderred this same thing. I don't see why you couldn't s-can everything up front and then get a coilover setup to fit in the stock strut location. Add a tube subframe and a rack steering.... sounds good to me.

http://www.fl-thirdgen.org/blacksheep-1/camaro.mov

 

Thats an a good video, your car sounds awesome, very mean. Nice wheels too, it just adds to the meaness

 

Thanks, coming from you that really means something
(it's 305 )

 

less weight, potential for better steering, adjustable ride height. one of the companies will add gussets for extra support on the crossmember for autox/roadrace, i dont remember who it was though. i guess that they had problem with the stress associated with turning.

 

I asked the same thing. I think there is major weight reduction in going with a tubular K-member and A-arms, but I don't think you are going to lose that much weight with the coil-overs. I chose to go with a "road race" k-member, with bracing and kept the stock coils.

I questioned how strong the strut towers were, since they were never designed to support the weight of the car, they were just a shock mount point. They likely are strong enough, as many people use the coil-overs.

The other part is the actual weight difference. From what I can guess, the coil-over spring will be lighter, since it is smaller in diameter, but I am guessing not much, maybe 2 Lbs a piece.

The advantage of the coil-overs though is the ability to adjust corner weights and ride height.

There are also some posts about people not happy with the coil-over setup for anything but drag racing. You may what to do a search.

I think most of the weight reduction again is in the k-member and possibly a rack setup. It all depends on how much you want to spend to shed a few pounds.

See the group purchase above (suspension forum sticky) for the Pro-fab K-member. You can order the road race option with additional bracing, right now it is a great price.

 

I also question the strength of the strut towers. I dont think they will break or anything, but I'm worried about flex. You can use weight jacks and adjustable dampeners and you'll almost have as much adjustability as a coilover setup. You just wont be able to change the spring rate without swapping the springs. If weight is a concern you can get the GC front struts, they are the lightest ones I know of and you can order custom valving. I've also questioned the strength of the tubular k-members, but now that they have one for "roadracing" I might consider it.

 

The Ground Control front weight jacks can be adjusted without removing the springs with just a ratchet and a 10" long 1/2" extension by going up through the lower arm.

The other thing that I question about coil-overs on a 3rd gen (other that whats already be mentioned) is that the mass of the springs are being move up and farther out from the center line.

 

The polar moment of inertia change is probably nill, but the real advantage is the springs i'm guessing weigh in at half, the stock coils.

I was also worried about the strut towers flexing along the axis of the coilover. I'm pretty sure i could triangulate the towers for shears and horizontal loading, but vertically? It might not even be worth it.

I was going to get some new Koni struts and shock, but then i started thinking, hmm maybe i should go coilover.

I'm gonna try researching, but i can't really find much, all the posts on here are gone. I don't know where else to look except www.corner-carvers.com

Maybe i should just get a full frame or Corvette frame and swap the body on.

 

Both the fronts and rears can be adjusted (ride height wise) without removing the spring. I was referring to adjusting the spring rate itself. My friend has some really nice coilovers on his Nissan. He can adjust the ride height, spring rate, compression, and rebound 25 adjustments each. I envy him. Hahahaha

 

Crap so do i, they must have cost a fortune!

 

Coilovers is the way to go as long as there is adequate bracing done to the fenderwells to further support the coilover setup. The higher polar movement of the coilover is more offset with the reduced weight of the smaller spring setup and the lighter weight A-arm design(no more perch) use with them. Overall, the coilover setup is less unsprung weight AND most importantly- It is bind free unlike the conventional springs.

CH, How is you friend able to change spring rates without having to change his coilsprings on the coilovers? This is impossible from what technology I am familiar with.

 

I can see it happening it there is something to compress and uncompress the spring, and another adjustment to offset the decrease in heigt. It would have to have two adjustments, one for the spring and one for ride height. I don't know if this is how its done, but...

 

Yeah it is double adjustable or something. I cant honestly say I know how it works either. This stuff is from Japan, brands like Kei Office, Tein, JIC, etc. None of those companies make stuff for 3rd gens Camaros. An interesting fact is that the AE86 Toyota Corolla runs the same exact types of shocks in the rear as a 3rd gen. I know guys that run 3rd gen rear shocks on their AE86's. I guess in theory any of these Japan coilovers made for the rear of an AE86 should fit on a 3rd gen Camaro. If I were to run coilovers I'd probably go that route in the rear as an experiment.

 

CH, I checked out the products you listed and will try and explain how it works.

The Tein "RE-type" Coilovers do have a preload adjustment for the spring tension. This damper has a separate ride height adjustment that is designed into the base of the strut assembly also. The ride height adjustment will lengthen or shorten the overall extended length of the strut by adjusting the portion of the body betwween the bottom mount and the damper housing. The upper (normaladjment on typical coilovers) is thensnugged agains the coil itself forcing the shock to be extended fully even when not installed on the vehicle.

Now here's the catch, every coilover will snug the coil against the upper hat forcing the shock into full extention when not installed, but not at the lower ride height settings. If the sping rate used (For example) is 300lbs at 1inch compression and the cooil is installed onto the coilover assemby with the preload of 1/2" uninstalled on the vehicle, then once installed on the vehicle it may set at 1" compressed (Or the desired 300lbs rate). Now with that, the full extention travel of the strut will now be compressed 1/2" (Meaning you have a 1/2" of unloading suspension travel in case that wheel hits a dip). It will remain in contact with the ground better because it can drop out. That 1/2" at the spring geometry can mean about 1" travel at the outer wheel travel geometry.

With the RE type preload setup, You can now crank prelaod into the coli and compress it 1" pre installed on the car (or even more)then once installed, that same coilrate on that RE-type strut will sit the car about 1" higher (outer wheel distance to fenderwell) and then can be adjusted that 1" lower by using the strut body adjustment at the base. What is now happening though is the strut has no unload travel because at ride height it is fully (Or at least closer to fully) extended because of the spring preload. If that wheel goes over a dip in the road the tire will lose contact with the road.

Basically, the RE-type setup is a very nice setup to maintain preload on the springs before they are loaded (installed on the car with vehicle weight) but are not designed to crank the spring tension stiffer or softer with this adjustment. It is still manditory for proper suspension function to install a stiffer rate spring by changing it out completely. Standard coilovers without this preload adjustment simply use a very soft preload spring that completely comlapses when any weight is put onto them (roughly maybe a 25lb rate preload spring) thuis simply takes up any loose gap that may occur if the car is jacked off the groung-or- the car does get airbourne enough for the spings to completely unload and possible come unseated off the retains. That "airbounre" is some serious hang time needed for that to happen but some of the Rally car drivers are accomplishing this with about 3 secs hang time and that is what this specific RE-type shock is designed for- not for streetdriving, drfting, or roadracing. This link shows the pretension spings and the basic principle of how a free standing coilover coil could come out of place(misaligned) if the tension spring weren't in there. The RE-type setup is just a very pricey upscale design of this tension or preload feature. http://www.colemanracing.com/section/index.htp?id=1123

 

Well, I know that Art Morrison makes a coil over conversion for the front and the piece that it uses goes over the factory strut. But like you said, it's probably meant for drag racing. Here is the page that I found the info...

http://www.google.com/catalogs?hl=en...519&catpage=21

 

Your right, I miss-read.

After rechecking that front suspension that my car I don't think that I could use coil-overs on a car setup like mine. With 275 tires on the front there is less than 3/4 of and inch of space between the tire and the strut. I'm also running 2 degrees of camber and this caused me to have to grind on the lip on the struts mounting bracket so that is doesn't hit the inner fender well during movement. Lastly I run Ground Control Camber plates and the strut shaft comes very close to the edge of the strut opening. The suspension maxs at 2.25 degrees.

 

Axoid, I ran some #'s on your setup to see why you are so close and what can be done if any to correct your geometry. With factory scrub radius combined with your offset of your new wheels, you are sitting neg 1/4"- 5/16" on each side than you should be.

What this does?
1) Makes turn in steering effort easier, Makes turnout effot harder.
2) increases force on inner wheelbearing corning cornering ratrher than evenly ditributing between the inner & outer.
3) throws off you ackerman angles more the greater the wheel is turned.

If you were to correct the offset postive 1/4" (via wheel spacer, 1/4"-5/16" is safe) it will put these setting back to proper specs.
If the car does start to push slightly on turnin, then expand the toein slightly say -1/16" to -1/8" more towards o* or even postive and that will correct any understeer gained in changing the geometry from current.

This will give you the proper clearance with the 275/40 17" tires gap between the strut housing. You stated above that you currently have just less than 3/4" and it should be at 1 to 1 1/16" gap regardless of camber (Camber has no affect on this). With this back to factory geometry, you now have the proper clearence for coilovers if wanted. The coilovers can also be run with rodends to bump the track width out further and give greater neg camber angles without rubbing, however, this again starts to give the oppsite of "what this does" above. Yet, postive scrub and track is better than neg in racing senerios, though equal is best.

Wider tires with positive offset (and scrub) combined with large neg camber (-2* and more) will compensate the outer edge of the tire on turnin and lessen the lift making it still closer to factory steering effort on turn in and yet the car will correct itself fine on exit also.

 

Did you take in account the at the 1LE brakes already move the wheels 1/4" further out. If I add another 1/4" the wheels will rub.

My car has amost zero push at entry and at the mid point of a turn, I have to over cook major to get a push. The car is loose on exit.

 

I did figure you had 1LE brakes up front (factored in the extra .318" offset for those) I was only giving what factory geometry was. Of course- if the car works don't touch it- I was merely giving a starting point reference and then you know the adjustments from there. Outward tire rub is a problem with these cars lowered with wider rims.

Fine in and through, but loose out can be helped with either one or both of the below
1) lower rear roll center
2) shorter TQ arm

If you loosen the front bar, it will affect going in- don't want that.

Don't get me wrong, I'm not critising your car by any means. I was just elaborating on the potential problems adressed with going to Coilovers in your case and how to possibly correct them to make it work if wanted.

Your car sits nicely in the picture

Dean

 

Don’t worry I haven't taken any offence. I’ll be the first to admit that I’m no engineer and all the development I’ve done on my car has been through trial and error and a little luck.

I believe that most of the turn out looseness is caused be the combination of the T2-R the heavy rear springs and the size of the rear sway bar. I’ve already dropped the rear bar size once (25mm -> 21mm) and it improved next I’m going to drop spring rate (175lbs -> 150lbs).

My car sets about 1/2 an inch higher than the picture shows, because that was a fairly hard turn.

 

Why don't you just try going down to an 18mm rear bar? Keep the 175lb rears if possible. That would be a better combo IMHO, for limiting roll, without lifting the inside rear....something your don't want to do with a Torsen, even a T2R.

Depends on your front spring rates and Bar of course.

 

i have yet to see one break, although i have yet to see one be put through the paces of a full race season. the ocassional weekend auto-x/drag and street use have been fine. although i've only had mine for 2 years i haven't personally known anyone with them longer then 5 so the true durability is a question i suppose.

it is obvious that bracing can be made and without the bracing cars are doing fine with them. good luck with your decision. the only thing that seems to be taking a beating are the strut plates and this problem is mostly avoided with similar upper mounts offered by art morrison. the billet plates are particular easy to bend with coilovers but the stock units hold up better.

 

That's another option that I am considering. I'll most likely try both to see which works best for me. The car rotates well and I don’t want to give that up to tighten it up on exit. I’m also looking at an adjustable torque arm.

Current setup:
Front:
34mm solid Spohn sway bar, 800lbs springs, 6 degrees caster, -2 camber, 1/8 toe out, ~1/2” drop, STB, wonder bar, poli bushings.

Rear:
21mm solid GM bar, 175lbs springs, ~1/2” drop, stock torque arm, stock lower arms w/ 1LE bushings, tubular pan-hard rod.

 

Give me a PM and I'll give you my setup. Works very well if you like a car to be very much " One the nose".

 

I'm using Konis in my car (shocks/struts/springs) and stock sway bars with the hard bushings. It's pretty neutral, I've just ordered up a set of sticky Yokes. I have a set of Koni bars around here somewhere.
There seems to be 2 ways to go (generally speaking)
Group A likes to run a soft suspension with big bars, the idea is that the soft springs will ride over the bumps and stuff and the bars control the roll.
Group B feels like you should stiffen the whole car and then use the bars for fine tuning.
There's pros and cons to both, my car is pretty stiff and the course I run is not flat (for drainage) and the super hard settings are great for the level part, but when you come to the irregularities, it stinks, the IRS cars kill me. On the street, I can run over a dime and tell if it's heads or tails.
http://chevyhiperformance.com/howto/4530/
http://chevyhiperformance.com/techar...18/index3.html
Hope this helps