Tubular control arms suspension upgrades worth the expense?
 

I have my '71 GTO in the shop rebuilding the TH400 and installing a new posi and 3.55 gearset. While looking under the car, I can see the front and rear control arm bushings are all shot and the shocks date from 1989. It was pretty much a reality check looking at the derelict underside compared to the shiney topside.

I am thinking about putting on new tubular upper and lower control arms which have poly bushings and new ball joints, rear tubular control and trailing arms w. poly bushings, KYB gas shocks and a rear sway bar. I am also going to do the Jeep steering gearbox swap. The car has a front disk brake conversion already and I may leave the rear drums alone for now. The labor to install the new suspension parts is no different than the cost to install all new bushings so I am thinking seriously about doing this.

Can I expect a huge handling improvement from the suspension parts? I am expecting the car will feel much more nimble, precise and well controlled. Right now it floats like a boat.

The remaining item is springs and this is the dilemma ... the springs are 44 years old but the stance of the car is perfect. I just know if I put it new springs, the car will stand taller.

Would I be giving up a lot of ride quality and control by reusing the old springs? My gut says the new springs will make a big of difference in the ride of the car also. Is there a way to check the old springs' spring rates to see how far off spec they atre compared to new replacements?

Could I buy 1" drop springs and expect the car to sit the same? The whole ride height thing is a crapshoot to me.

Any thoughts from someone who has gone through this?


https://imagizer.imageshack.us/v2/68.../dscn0084t.jpg https://imagizer.imageshack.us/v2/68...dscn0082rb.jpg

Why not just go with coilovers so you can set the ride hight just as you want it?

That was an option but the cost would be around a grand, I know they are engineered but it just seems wrong to support the entire weight of the vehicle on the shock absorber mounts.

Coil over kits should run you about $ 350.00 for your car & the coil over is supported on the lower control arm not the shock mount. The coil over shocks mount on top of the control arm for better support & it give you a great ride plus you have a lot more control over the front end height of your car then to. We just put a set on my friends 69 camaro & the total for the springs coil over shocks & the Torrington bearings was $ 362.00 & some change. The kit for your car is the same price as it will use the same parts. Bought right through Summit.

I don't know where you are looking, but the cheapest ride-height adjustable kit I see on Summit.com is $445.97 for the front axle and $569.95 for the rear axle, so basically a grand.

I talked with my friend tonight & he said he paid 445.99 for the front set. I thought it was the 349.00 so my mistake but that is still a good price for them, & all I was talking about was the front ones not the rear. We didn't put rear on his so I never got any prices for the rear. Usually you don't need them on the rear as your mainly putting them on the front to get it lowered because the rear is usually low enough. Once we dropped the front on his Camaro the rear was plenty low .

Well, I took the leap and will let you know how it turns out. Here's what I bought:

Ebay tubular upper/lower control arms w. urethane bushings and ball joints
UMI tubular rear control and trailing arm kit
Moog 5400 Front and CC5501 Rear springs
Hellwig rear sway bar
KYB Gas shocks for all 4 corners
Energy Suspension end links with urethane bushings
Energy Suspensions urethane sway bar bushings
Rear disc brake conversion kit with Caddy Eldorado calipers/ebrake
Moog rear spring isolators
GM proportioning valve kit w. lines
New brake hose lines
New rear brake hardlines
Carter M6907 mechanical fuel pump (taking out the whiney Holley red pump)
Cardone 1997 Jeep steering box
Lares 200 rag joint
Repro RAV Holley dual feed fuel hardline

I went with the Carter M6907 pump since the previous owner had pulled the return and vapor lines off the car and the carter pump did not require either. Supposed to flow 120 GPH at 5.5 - 6 psi.

I'll let you know how this turns out w. pics when done. Car had a front disc conversion done by the prior owner and no proportioning valve installed so the car really has always had poor braking. Should be interesting to see how it drives when done. With the suspension in place and the TH400 perf rebuild/3.55 posi in place, it should be much more enjoyable to drive.

Now I have to work on how I can make my "springy" stock seats (I put in new foam buns before reicovering them) feel like the new cars!

Keep us posted.

I am planning on purchasing UMIs full setup plus QA1 double adjustable coilovers front and rear. I still need to figure out which front setup would work best for my goals with the ATS AFX spindles.

Just some feedback on the Eldos - their e brakes weren't known for working well. I had that kit on my car, and ended up throwing it away in favor of a disk rotor with an internal drum for the parking brake. Had I known before, it would have saved me a few bucks.

I think I read that here on the board too. I haven't used my eBrake in the 36 years I've owned the car. It's an automatic, I put it I park. I saw where yours (4 speed) rolled down the driveway and into the street. Why don't you park the car in gear? I never rely on a parking brake (which is always out of adjustment anyway) when parking on a hill.

I paid $355 for the complete kit. The kits without eBrake weren't any cheaper because they put larger, drilled rotors and different calipers in those kits. Seems pointless to have bigger brakes on the back compared to the fronts that are on the car anyway. Honestly, I could have left the drum brakes alone and it probably would have been fine except the drums look dumb behind the 17" wheels.

Relying on a manual to stay in gear as an ebrake is a risky game. You need to use both, not one or the other. It is too easy to bump it out of gear, or for you to have not engaged it all of the way without knowing. Also depending on how steep your hills are, engine compression might not even be enough.

The front geometry is the issue here. In order for the parts to improve handling they have to address the front end specs. I fixed that with control arms that fix GM mistakes, matched springs/sway bars, and the Jeep steering box, mine handles as good as my Volvo R does around town and when pushed hard just above the speed limits. I used SC&C control arms and springs with Bilstein shocks.

The control arm set I ordered advertise their design offers improvements by increasing camber gain and improving roll camber. I didn't spend a bundle on the assemblage of parts so it will be interesting to see how it turns out.

Leaving a car in ist gear (manual) or Park (auto) is 100x more effective than a parking brake which relies on the tension of a cable to maintain braking force. How exactly does a transmission jump out if gear in a parked gar? It doesn't. The resistance of the engine's compression and the clamping force/friction material of the pressure plate/clutch disc far exceeds the clamping force of an emergency brake and cable. Come on, have you driven off with your emergency brake on? In most cases, you hardly notice it is on. Have you ever tried to push a car while it is 1st gear? The tires slide on the pavement before the engine will turn over.

That's a lot of nonsense coming from a guy who drives an auto.

A properly setup cable ebrake will not lose tension. A hydraulic one has an higher chance of losing pressure. A manual transmission car can be bumped out of gear by someone hitting it while parking, or by someone inside the car (say a passenger waiting, exiting, or entering the vehicle). Not to mention you can easily think you engaged the gear bit it just isn't quiet there yet.

No one is disputing the clamping force of a pressure plate.

Depending on weight and the friction coheficient of your tires, you could over come engine compression. While this situation isn't as common, it is possible. You must not be familiar with bump starting a manual.

Putting a manual in first gear and putting an auto into park at two very separate things.

As far as driving with an Ebrake on, yeah you can tell. You will have a difficult time taking off from a start and then rear will noticeably drag with a properly adjusted parking brake. It will be harder to tell if your driving an automatic, which simply has a go button and requires zero attention from the driver to operate.

Long story short, fix your ****ing ebrake. It'll hold your car in place provided you did it correctly. Don't rely on either a parking prawl or first gear to hold it in place. If you trust your brakes to stop your car you should trust them to hold it in place (along with an engaged gear or parking prawl). You just need to keep your equipment maintained, it could kill someone.

I trust a master cylinder and 4 wheel brakes to stop my car. I do not trust an emergency brake to keep my car from rolling downhill if left in neutral. A parking brake is intended to be used in junction with putting a car in park or in gear with a manual trans. It is not intended as a substitute. In the rare instance the parking pawl in the automatic transmission might fail (the only failures I have ever seen resulted from putting a car in park while moving), yes a parking brake serves as a backup. Additionally, the parking brake (or emergency brake if you prefer) provides mechanical braking in the event of a hydraulic loss.

This is straight out of a current Chevy Owner's manual:

"Parking
If the vehicle has a manual transmission, before getting out of the vehicle, move the shift lever into R (Reverse) if parking on a downhill
slope. On a level surface or an uphill slope, use 1 (First) gear. Firmly apply the parking brake. Turn the wheels toward the curb for a
downhill slope, or away from the curb for an uphill slope. Once the shift lever has been placed into gear with the clutch pedal pressed in,
turn the ignition key to LOCK/OFF, remove the key, and release the clutch."

So go ahead and worry about the 1 in 10,000,000 chance my car will get hit from behind and shear off the parking pawl but be unconcerned that your car is parked in neutral on the hill and you are relying solely on your parking brake's cable adjustment to keep your car from rolling away because you left it in neutral.

Here's a pic of Turbo 400 Parking Pawl that would have to be sheared off to fail:http://www.atiracing.com/links/pr/20...400-Pin-sm.jpg

Your reading comprehension is dismal. I have stated multiple times that you are to use to two together, not one or the other. Either option ~should~ keep the car in place but **** happens, so you need to use both options to make sure your car doesn't go anywhere. You claim you have never used an Ebrake in the past 36 ears, good for you. Fix your **** and use it.

That picture of the pin is useless for proving your point. I know what one looks like, and has neither a scale, nor 36 years of parking abuse.

Also, that Chevy example is exactly what I have been saying. Did you also happen to notice that in their instruction, at no point is the weight of the car resting on the drivetrain? It's all resting on the emergency brake and hoping that in the event of a failure, the drivetrain will catch and stop the car.

No problem. I am just saying that with these older cars, the contribution of the parking brake IMO is less than the putting the car in gear.

Sounds good. I have only driven my cars aggressively on a few courses, more so on the street by challenging newer cars here in Colorado who do not expect the 442, the Buick, or my Volvo wagon to enter a corner at speed. A few things I found to be at issue after the updated parts were installed was a shop or friend to align to updated specifications and spring rates that create pitch when pushed hard over uneven pavement. I noticed this issue on my 87 Buick T when I used Moog springs. It would pitch rear to front when turning and accelerating through an intersection and exiting the turn. The first time this happened it unloaded the rear tires while the turbo was spooling. Needless to say the Buick earned a story that day as a few fellow car guys and I were headed to a local get together. It felt more like my 74 Dodge 100 then a well balanced car.

I just want to share why it is important that all parts work together. At times when issues arise we need to troubleshoot the "why" did it do that. Even stock parts give us fits.

The other discussion on the parking brake is we all have to decide when any issue should be corrected. Whether we used a vise grip to seal a ruptured front brake line in 1982, ignored a trashed/faulty wiring harness, or had a 72 GTO with no rear brakes at all with a good pedal because the rear line was pinched off; just for a test drive. I am not admitting to these infractions but they do arise hopefully we have all learned a few things from owning these fabulous cars over the years.

I would recommend fixing it sooner than later to protect your GTO and the other guys rides that you call friends. Especially after you get the new susp parts installed.

I wish you the best when the parts arrive.

Maybe you have but, if not take a look at a few books or articles on making our cars handle. Pro-Touring dot com or Lateral G has some good info.

Lance

Ever push-started a car with a dead battery?

Yep, many times. If you are going to tell me you and your other super hero friends were able to push the car in 1st gear or reverse from a dead stop, then fly on over here with your super powers so I can shake your hand.

Have 2-3 guys push a car in first gear, clutch pedal in, ignition off, to a running pace. Drop the clutch in 1st and see what happens. I'll give you a hint, the car stops ... very quickly.

As kids, we figured out pretty quickly you could not overcome the engine compression (braking) in first gear so we used 3rd or 4th when push starting. The torque multiplication is reversed.

Lol. Just no.

I can't tell if you are that dumb or a troll.

Sounds like a wild ride. Was it a mismatch of the spring rates? Weak shocks?

It was the springs, it had Bilstein shocks. Replaced the springs all was well, picked up tall bj for UMI upper and lower control arms. A week later a guy shows up and bought it with no test drive, and drove off. Just like that...now I am considering a 71 or 72 Lemans 350, cam, minor head work, reworked Q-jet, 5 speed, Corbeau seats, and a 90hp nitrous kit.

Could be fun...

Im going to do you a favor here. Its going to sound harsh but im just going to say it......You need to send a lot of this stuff back. Eat the freight and send stuff back.

Ebay tubular upper/lower control arms w. urethane bushings and ball joints chinese junk that I wouldnt put on a go cart. Go over to pro touring.com and read about these. Buy from UMI, Ridetech, SC&C, BMR, Speedtech anyone but these ebay POS arms.
UMI tubular rear control and trailing arm kit. Great company and American made. Are they adjustable? If not send them back and get adjustable arms
Moog 5400 Front and CC5501 Rear springs Buy a good aftermarket spring from SPC, Hotchkis or someone else the generic repop springs are junk
Hellwig rear sway bar Hellwig makes good parts
KYB Gas shocks for all 4 corners Send these shocks back and at least get Bilstiens. If you want a fixed valve upgrade look at Ridetech or Chassisworks
Energy Suspension end links with urethane bushings
Energy Suspensions urethane sway bar bushings
Rear disc brake conversion kit with Caddy Eldorado calipers/ebrake I used these for 3 years without issue. You will have to shorten your ebrake cable though
Moog rear spring isolators
GM proportioning valve kit w. lines
New brake hose lines
New rear brake hardlines
Carter M6907 mechanical fuel pump (taking out the whiney Holley red pump)
Cardone 1997 Jeep steering box excellent upgrade for thee money
Lares 200 rag joint
Repro RAV Holley dual feed fuel hardline

Totally agree when it comes to the springs, have to buy quality ones from a reputable seller or you will struggle with lean, uneven stance, and uneven rates. My preference is Global West, and I avoid Hotchkis.

Bilstein's all the way. For the money, they are the best deal out there. eShocks.com have some of the best prices for them.

The Right Stuff rear disc kit is a much better option, and the calipers are better than the eldos. Think I paid $440 for my setup on the 442 with an ebrake.

Right Stuff sells the Chinese tubular arms and they're fine. I found a set on egay under a no-name and were the exact same ones. The uppers have issues I've heard, but I used GWs, because I am running tall spindles. Some say the Chinese uppers cause the alignment to not reach desirable specs.

Sway bars are pretty much sway bars, and I prefer not to drill holes in my floor to mount them, so OE style is fine for my stuff.

On my LeMans, I have AFX spindles, and C5 brakes. The CPP spindles the jury is still out on, but I plan to throw a set on the 442, once I do, I will do a comparison to the AFX. But for the money, even if they are slightly off from the AFX, it's the best big brake and handling deal out there.

I run 9" dual diaphragm boosters and disc/disc combo valves, vette masters. The 442 will throw you through the windshield, the touch/feel/modulation is almost like a new car, no joke. It has OE 11" on the front and the Right Stuff rear kit, works great for just about all kinds of driving on the street. Only reason to go bigger on that car would be autocross or track. The LeMans brakes are a good step up, and I've done panic stops from 130-140mph and not had to pray. I've spanked exotics with the LeMans in the handling dept, and not with shabby drivers behind the wheel.

.

This is very good advice.
I'm doing the Stage 2 kit from SC&C - SPC uppers + balljoints
Freshen up the pads and rotors.
Springs and shocks - MOOG year one 20 yr old stuff has to go.

Then a set of slicks.

Pretty much eats up the budget for now.

You amuse me.

As you do me.

But possibly for not much longer considering those Chinese A arms.

Yah, I'm kind of speechless here. Yes, I've push started a car in 1st gear plenty of times. We usually used 2nd though because it spins the engine faster. I've never once not been able to get the engine to turn over in 1st gear.

Thanks for the brotherly advice. Unlike vDub. I will admit when I am wrong. :D

This whole mix and match of parts has me worried from a functionality standpoint. The two main items being the springs (spring rates and ride height) and the eBay control arms.

I looked over the parts and talked with the shop about the controls arms. 1) the shop owner couldn't believe how good they looked in terms of welds, powder coat and ball joint quality. 2) We both agree that until they're mounted and at the alignment shop, I'll never know if they are going to work as intended and then it's a little late. 3) Same goes with the springs. Until the car hits the shop floor on all fours I won't be able to judge the ride height and ride quality. Like you say, probably better sourced as a complete kit rather than "parts".

I can't argue about the Bilsteins, no doubt they build a better shock and better shock has a tendency to level the playing field on the spring rates and rebound characteristics.

I am going to slow the play down a bit and some more homework on the alternates you have suggested. The shop is starting the trans and rear end tomorrow so I have a few days to kick it around.

Thanks for the critique and experience share!

Do yourself a big favor and call both Mark Savitske at SC&C http://scandc.com/new/ for your suspension components and Tobin Knighton at KORE3 http://www.kore3.com/ for your brakes.

Both of these gentlemen are great on the phone and have many options they can offer you depending on your needs and budget.

I sourced nearly all of my components from them, both gave great technical advice that was easy to understand and steered me towards the right parts for what I was wanting to do:
http://forums.maxperformanceinc.com/...d.php?t=610357

I agree with the Savitske call - no need for lower arms here.

We do make a nice rear drum-in-hat setup, will work with bolt in axles too without shimming, bigger caliper pistons and ebrake shoe is externally adjustable.

http://forums.maxperformanceinc.com/...1&d=1396747314

Yup, Mark literally wrote the book on suspensions. He is a wealth of knowledge. I'm still trying to understand how it all works.

But yeah, shocks and springs have to work together.

Scarebird,

Does your drum in hat kit work with C6 calipers and rotors ?

Thanks,

Kurt

Are the front arms you bought Scorpion brand? (Hope not)
I have all UMI rear suspension and it went together well. Haven't driven it yet.http://images.tapatalk-cdn.com/15/06...32ab2f0e52.jpghttp://images.tapatalk-cdn.com/15/06...17703e4f9a.jpg

Yes, Scorpions in front, UMI in back.. You didn't like the Scorpions? The set I got look very good in terms of welds and fitment, All bushings are Delrin with grease fittings and spherical rod ends on the sway bar ends. The looked very beefy and fit very well. Haven't progressed to alignment yet though.

I did the mix and match parts and my car drove so bad I mostly kept it parked the last few years. This year I spent a small fortune swapping out parts, but well worth it.

KYB shocks are the worst. Might be ok if you they were put on a car with factory saging soft springs.
I agree 100% on the factory style springs. Stay away.
Take Nike67GTO advice his car rides awesome.
Also what B-man said. I hope to go with the SC&C stage II myself on my 64.

If you decide to use the Chinese upper arms replace the ball joints with moog or maybe Howe if you want to go with a taller joint. 2 people on the Chevelle forums have had the ball joints catastrophically fail. Luckily no one was hurt. Another person had the welds x-rayed and they passed. The arms themselves seem to be sturdy enough but some have reported geometry problems and difficulty aligning but that could be from frame sag.

For me....I don't care about Chinese engine parts. If the engine comes apart...well whatever. Now if your front end comes apart you could be done. At a minimum your car is going to be a mess, just to save a few hundred bucks. With American made arms from SC&C, UMI, Ridetech, BMR, Speedtech you get quality parts in a CRITICAL safety spot on your car. You also get top shelf customer service and support. I'm willing to bet the guy selling the cheap arms doesn't hardly know the difference between camber and caster....

I thought the arms themlves were pretty well made, the ball joints looked a bit cheap. I may buy the Moogs. $100 for the uppers and lowers is cheap insurance to have quality ball joints.

Just a quick update. I just installed my rebuilt third member and went to install my rear disc kit. Not exactly the bolt on kit I thought I had bought. There are tabs to terminate the rear axle hardlines and connect to hose to the calipers that must be welded to my fully painted rear axle ... Crap. The manuf couldn't have welded tabs on the back of the caliper brackets? Stupid of me to believe the kit was a bolt on I suppose.

Here is the best part ... The rear rotor hats are too small to fit over the axle flanges. The enclosed instructions did not call this out but More detailed instructions downloaded from the supplier's website provided specs. I had to pull the axles and find a machine shop to turn the flanges down. Unfortunately, my newly installed axle bearings and seals will have to be removed and replaced to allow machining. The shop says new bearings and seals will be needed as the newly intalked ones will likely be damaged pressing them off.

I am a bit pissed that the brake conversion kit instructions were so vague but I guess they assume you would just intuitively check the rotor fit before proceeding. I tried 10+ machine shops/driveline shops before finding someone who could do this and will be waiting at least a week to get this done. Nuts.

Correct, not your kit. I wouldn't be comfortable with a soft clamp pinching a rubber brake hose to keep it in place.

The provided tabs have a hex hole to engage the brass hex fittings and lock like factory so I will use them. I could fab new hard lines from the rear axle T all the way to the calipers but I had already bought the replacement hard lines before deciding to go with the disc conversion so I will shorten them.

It just seems dumb not to have the caliper brackets fabbed with tabs already in place. With a simple bend of the existing hard line, you could attach to the hoses and have a bolt-on install.

The machine shop does not want to turn the flanges down by clamping onto the raw forged section of the axle. They are concerned that the run-out will result in imbalance so they want to clamp onto the machined surface where the bearing now resides. I think it is overkill but I don't have a choice since they are the only game in town beside Opel Engineering ($$$) that can do this. I would have thought any place that machines rotors could do this but apparently not.

It is amazing that none of the so-called driveline, axle and driveshaft shops do not have the capability do this.

can you machine the rotors and open them up instead? I would think that would be easier.

There you go. That is what I was grousing about with the kit I bought. It comes with the soft line tabs but they have to be welded to the rear axle housing (they are radiused for this). I could grind them and weld to the back of the brackets but the soft brake lines furnished in the kit would be way too long. I have to shorten and flare the hard lines to terminate at the tabs after they are welded in place on top of the axle axle housing about 6" in from the axle flanges ... bolt-on kit they (Inline Tube) said, but I guess I should expect this kind of thing from a $300 kit (rotors, brackets, loaded calipers, ebrake cables, hoses, etc.) right?

With regard to the machine shop, I can't really tell the only place in town who can do the work, how to do the work there are no alternatives. I live in the NW Suburbs of Chicago and could find no one able to chuck the axle in a lathe and turn down the hub, as crazy as that may seem. You would think any axle/driveshaft shop could do it but everyone's solution was to call Moser and order new axles with the reduced flange size.

Also, someone commented about cutting the inside of the rotor. The manufacturer included a warning/disclaimer against doing this as too much material must be removed. I didn't throw a caliper on it but I am guessing .050" would have to be cut plus a corner chamfer to allow the flange to seat fully.

Yeah, this is something I could have done in HS shop class.