: shocks,springs,brushing help?
Dec 20th, 99, 02:00 PM
I am looking for someone that has any knowlege of the different between PST polygrapic brushing,ground zero springs and global west dell-lum brushing and there springs.
I would like to keep stock a-arms.
I do not mind paying more cash but is there a BIG difference between the two.
Dec 20th, 99, 06:23 PM
Polygraphite are touted as "self lubricating" that eliminates squeaks but I've seen properly lubed polyeurethane work fine. They both have the same stiffness, near zero deflection. As for the Global West stuff they have a aluminum bushing that has a Derlin plastic which eliminates metal to metal contact. They also have lube zerks for periodic lubrication. These are more expensive but offer little more in performance, if any, than the others above. As for springs, as long as you go with a good spring company such as Detroit Eaton, Landrum, Hotchkis or Eibach, the quality should be comparable. Just talk to a few people and see what has worked for them for thier specific needs. I have been told that 600 lbs. in the front with all iron engine, steel hood, etc. and 175 lbs. in the rear should be about max to retain some comfort (these are pretty stiff springs!). Keep the front sway bar around 1" and do not use a rear bar as the early Camaros tend to oversteer. The stiffer rear will exasperate the oversteer in these cars. Bilstein makes good shocks for these cars too.
Hope this helps
Dec 22nd, 99, 07:12 AM
My experiences have shown exactly what Joseph has stated.
Dec 22nd, 99, 07:11 PM
I was going to install the rear sway bar on my 67, but above you wrote
"Keep the front sway bar around 1" and do not use a rear bar as the early Camaros tend to oversteer. The stiffer rear will exasperate the oversteer in these cars."
The rear sway bar should help the car hold the road better, is this not true?
Dec 23rd, 99, 03:43 AM
If you want something really trick? I use Adjustable coil overs in the front of my 69 and a company called proshocks makes them. A company called superior spindles makes the install kit. The coilovers are adjustable and I can raise or lover my ride height and the springs are rated at 500. 550 or 600 is not really needed for highway speeds and 500 pounders still let you feel every bump as it is. I can take a nice curvy off ramp at two times the posted speed limit without to much concern. As for rear sway bars, save your money and invest into some really nice rear springs and poly bushings. Note: its good to get the best you can get but sometimes the cost is not worth the gain. If you are driving the car on the street only...dont be too concern with gettng the absolute best...let the "on track" guys buy the exotic stuff and leave a couple of bucks for the brew after a long day of cruising. http://www.camaros.net/forum/smile.gif
Dec 23rd, 99, 06:30 PM
Roll bars limit the amount of body roll by placing more weight on outside tire in a turn. If I remember correctly, a rear roll bar takes a greater percentage of the car's total body weight and moves it to the rear outside tire in a turn. Stiffer springs do a similar thing, place more weight on the outside tire, by limiting body roll but in a different manner. Each car chassis has an optimal spring and roll bar setting. This optimal setting has many factors associated with it. If too much weight is placed on a given tire in a turn it will lose traction. This is what a rear roll bar does to early Camaros. It is hard for me to explain this fully but if you are interested there are plenty of books out there dedicated to general suspension theory. The two I have and refer to are from Steve Smith Auto Sports books. They have a web page, check them out. Also, to add evidence to this and to the best of my knowledge, all the Trans-Am racers in the 60's did not use rear roll bars on their cars and these cars were set up for optimal handling.
[This message has been edited by Joseph (edited 12-23-1999).]
[This message has been edited by Joseph (edited 12-23-1999).]
Jan 3rd, 00, 09:35 AM
I'm posting again because my last post gave incorrect info. Here is the deal with roll bars. Roll bars limit body roll by placing more weight on the inside tire during a turn not the outside tire as stated in my last post. Springs limit body roll by placing more weight on the outside tire in a turn. What technique to use in limiting body roll depends on the chassis setup and weight distribution. Generally, it is best to use a lighter spring to combat braking and bump force and have a roll bar combat body roll. This is where things get tricky for me to understand and consequently to explain. There is a term Roll Couple Distribution which measures the percentage of body weight both front and rear tires support in a turn. This distribution is base on the front and rear weight of the chassis. Both tires should have equal weight given each tire is the same width and a weight distribution of 50-50. If one tire sees too much weight it will lose traction. If a rear bar is use in early Camaros a larger fraction of the total body weight is loaded onto the rear outside tire resulting in loss of traction. Not good. If you need more explaination than this check out Steve Smith Autosports book Advanced Race Car Suspension Development.
Jan 4th, 00, 06:04 AM
One thing to remember here is that the "reason" early Camaro's don't like rear sway bars is because the outside front tire cambers out in a turn, reducing it's contact patch and traction and causing understeer, which the rear bar exagerates. I've read about an enormous number of things to fix this, including spindle extenders, custom a-arms, and relocating the upper a-arm frame pivots. Does anyone know what actually works without breaking the bank. I can't afford a customer subframe and vette suspension!
Jan 4th, 00, 08:30 AM
Someone please respond to JimM. I will also be upgrading my front suspension this winter and would like to know the available options.
The cheaper mods I have heard of include:
1> the Guldstrand modification whereby you change the location of the a-arm shaft by modifying the shaft bracket welded to the frame.
2> spacers that mount between the a-arm and the ball joint.
I have talked to someone who did 2> and was satisfied, but haven't talked to anyone who has done 1>. It seems to me that if they both accomplish the same thing, 2> would be better because you don't have to cut anything up.
Jan 4th, 00, 06:18 PM
I have driven in a 68 car with the Guldstrand mod. and it seemed to handle well. I plan on doing this mod. to my 69 shortly and may try adding a spacer as well. I have to get a suspension program so I can plot the different changes and see there effects on paper first. Things of concern are ball joint bind, the need to offset the ball joint location to correct static camber and any bump steer that would be created. I'll post anything useful.
Jan 5th, 00, 04:22 AM
See "relocation of upper a-arm" discussion topic below dated 12-9-99 by MarkM. There are some additional relevent points in that discussion.
Someone mentioned that you probably would NOT want to do both mods because the combined mods might create too much negative camber.
I think I am leaning towards the Guldstrand mod for this reason: It's been around as long as the car itself. The spacer seems like a logical, simpler fix than hacking up the a-arm shaft mount. If the spacer was better, Guldstrand would have used that on his Trans-Am cars instead. I can't imagine that they didn't think of the spacer idea back then.
Jan 5th, 00, 05:55 PM
I agree that Pro Motorsports spindle extenders used in conjunction with the guldstrand mod. may produce too much camber gain. What I was thinking of doing is using taller and fatter ball joints instead of the spindle extenders. I came across this in Steve Smith Autosports book called Street Stock Chassis. They modified a 1970 Camaro front end with larger Chrysler ball joints I think. I just when to find the book to verify this but it seems my two year old got interested in it and subsequently misplaced it. Kids, you gotta love them! Anyway, the larger diameter allowed them to offset the location of the ball joint to correct static camber. The reason I have not jumped right in is because the suspension is differnet for the newer Camaros. But I have to believe that something similar could be implimented in the early Camaro situation. As for why Gulstrand did not think of the larger ball joints is maybe he was limited to stock joints. Anyone have any other thoughts on the larger ball joints?
Jan 6th, 00, 07:05 AM
My car is the one that Joseph has taken a ride in. It has the Guldstrand modification and full suspension. For me, there was one major benefit and drawback for each system. The Guldstrand mod is proven, but does require cutting the frame. Though you can grind the A-arms to clear the frame, I did not like the idea due to the importance their strength. The extenders are easy to put in, but I was concerned about the structural effects that the extender would have on the ball joint/mount. Though the ball joint acts as a hinge, therefore relieving the A-arm from bending forces, I am still unsure about their effect on all of the components. I like Joseph's comment on the longer ball joint. In that case, you are using a component that is designed to be that length. My decision to go the Guldstrand route was based on a conservative approach, which by no means is right for everyone. One last thing to consider: I drove (hard) this car as a daily driver for 10 years. The only time I had to replace tires was when the outside of the tire was worn out because of the geometry problems. I would do this mod again just for that reason alone. As others have said, "just my 2 cents worth."
Jan 6th, 00, 09:06 AM
I called and got some info on the Guldstrand mod. They say their mod will provide more camber gain than a spindle extender. Also, they said their mod does not upset suspension geometry while an extender will (I bet there is a fix, but didn't ask since they don't recommend the extenders).
Answers to other questions I asked:
- 1 inch front swaybar is the largest they recommend. NEVER use a rear swaybar.
- maximum lowering before you start affecting suspension geometry = 2 inches
- stock five-leaf springs are good enough for the rear
- they don't focus on spring rate. Wouldn't give the spring rate for their coil springs. Said there are too many variables that impact the number and that it is basically meaningless. Their springs are stock height and they come with instructions on how to cut for the ride height you want.
- recommended poly a-arm bushings
Thought this information was worth sharing.
Jan 6th, 00, 09:50 AM
Yeah thanks for the info., It appears there are quite a few people wanting to maximize there camaros handling.
68 468 700R4
Jan 7th, 00, 05:32 AM
Interesting stuff, hopefully I'll be able to put some to use now! Where can I find Pro Motorsports spindle extender info (www)? Guldstrand catalog is on the way, but I'm not hot on grinding a-arms or cutting frame rails! Global West has some real trick stuff, but way out of my budget! There are so many trick spindles, and so many interchangeable ones, does anyone know of a spindle that'll a. fit, b. mount factory style disc brakes, and c. be an inch or two taller from ball to ball than the stock spindle, and d. (I'm reaching here) lower the front end 2"? Answer to our prayers, if it exists!
Jan 7th, 00, 08:32 AM
Based on my discussions with Guldstrand, I don't think you can simply replace the spindles. A taller spindle will upset suspension geometry. That's why Global West's suspension system is so big and expensive. If you make substantial changes to one part, you have to make changes to the other parts (where have you heard that story before?).
I may hold off on buying or doing anything to affect chamber. It seems like a lot of new stuff could be in the works and I don't want to spend the time and effort at this point.
Go to drgas.com/promotor/article1.html for info on Pro Motorsports spindle extenders.
[This message has been edited by gheatly (edited 01-07-2000).]
Jan 7th, 00, 08:57 AM
I think I will just do the Guldstrand upper control arm relocation modification. There is really not very much material to be ground away to clear the control arm, so if for some reason you want to put it back to original you could.
Jan 9th, 00, 08:04 PM
I bought the PST super performance front end kit with the polygraphite and I am very happy with the handling. Money well spent!
Jan 13th, 00, 11:49 AM
Thanks for the info. Guldstrand and pro motorports stuff is on the way... we'll see.
Jan 13th, 00, 12:05 PM
JimM are you going to do the guldstrand relocation of the upper control arms and the pro-motorsports spindle extender?