Need some real life suspension advice.

I'm building a 68 wagon, 454 low rev with an automatic. The wagon is going to be a reliable driver with the potential to be loaded up with 6 passengers and towing a trailer.

Front brakes will be a Baer disc kit, and thats about as far as I've gotten (alredy purchased)

Looking for info on front control arm bushings, rear arms and bushings, and coils Stock Rear with a slight drop in the front.

I want the vehicle to feel tight, but still have a smooth reliable ride.

Poly/Polygraphite/Rubber graemlins/clonk.gif graemlins/clonk.gif too many choices.

I am going to ASSume that you got the "tall" spindles with the Baer kit. You may want to look into Pole Position arms, especialy with the B/B. Getting it aligned may get tight with the girth of a B/B.

Polyurethane and polygraphite are almost the same except that poly graphite has graphite in the poly....which deteriorates them. I wouldn't run polygraphite in anything.

Poly is fine for front arms and sta-bar bushings.

When you get to the rear I recommend either Edlebrock, Currie or the UMI arms we are discussing in the other thread. Avoid poly in the rear at all costs. There are probably some straight lne guys who will tell they work fine...they don't don't know any better. Poly in a converging link system does not work well in any type of driving. For a street compromise run the rod ends at the frame side and rubber on the axle.

I would run Moog replacement rears and some Hotchkis or Edlebrock fronts.

Rob,if you're not trying to build a G-machine,your stock spindles will work fine. Not everyone wants or needs the tall units.
I ran polygraphite bushings in the front suspension of my former 68 Elky BB car for over five years with good success and no squeaks. Never saw any deterioration as Dennis mentioned but I guess anything is possible.
Something else I would recommend is a larger 1 1/8" or 1 1/4" swaybar with that BB. What rolling stock are you planning?

Clint and Dennis,

I'm not trying to build a G-machine, no autocross or sporting, no serious drags. I just want a strong rear susp that will handle some just for fun romping around town and the more common long highway trip towing a trailer.

I want the car to handle well with a full load and Feel tight. Not looking to blow the bank, but tight and smooth is were I need to be. Rubber seems to deteriorate too quick as this project is meant for an all weather driver.

The front is for stock spindles, its the eradispeed disc conversion kit.

My wheels and tires are 15x8 ralleys with 245/60/15 all around.

Good, stay with the stock spindles then. You could run SC&C's tall upper ball joints if you wanted to correct the camber curve condition.

Polyurethane bushings in the front, the rest of the recommendations stay the same.

Dennis and I spend so much time over at ProTouring.com,we tend to get carried away over here. :D graemlins/hurray.gif

Originally posted by dennis68:
You could run SC&C's tall upper ball joints if you wanted to correct the camber curve condition. What is this?, and is it worth it for a street car...I have to change the Ball Joints anyway. Do you have a link for SC&C.

Speedway offers the same thing for the upper ball joint (http://www.speedwaymotors.com/xq/asp/strBase_List./hilt./source.2191/base_no.91720032/str_base_no.000%2DCATALOG+RACE%2C91034323%2C910348 12%2C91082160%2C91088200%2C91089411%2C91720032%2C9 1720036%2C91720039%2C/header_title.NEW%21+Race+Products%2DBall+Joints/page_name.prod%5Flist%5Fdisplay%2Easp/search_type.L2%7E27/search_option./deptsearch./deptSearch_id.2/dept_id.L2%7E27/dept_id_p.2/dept_name./dept_name_p.NEW%21+Race+Products/ShowImages.yes/sq.0/cont.1/intPgNo.1/redirect./qx/product.htm) . Marcus at SC&S has a special ball joint he worked with Howe to get it is pretty trick and expensive. Here (http://www.scandc.com/) is the SC&C link. They have some real trick stuff.....but bring your credit card.

Originally posted by dennis68:
correct the camber curve condition Whats camber curve dennis?

onabudget,

dennis hates them and for the stuff he builds I can understand why
but, this rear setup sounds like a good candidate for variable rate springs and gas shocks
for about a 125 bucks it will help you out with the hauling and trailer
but if dennis finds out I told you this he is gonna be ticked :D

OK, suspension 101A. When you look at the front of the car (standing in front of it) the tire’s typically do not stand perpendicular to the ground….not EXCATLY perpendicular anyways. The amount they tilt in or out is camber. When you go into a turn and the body begins to roll around the roll center the tires will not stay at the same angle to the ground that they were. This is referred to as roll angle. In older Muscle car chassis’ the camber gain is wrong due to poor engineering. What this means is that as you corner you would like for the tire to tilt in toward the center of the vehicle more in order to retain as much of the contact patch as possible (think of looking up at the tire from underneath through a glass plate, the part that touches the plate is the contact patch and the only thing connected to the ground). In the older chassis the tire rolls out, going into positive camber. This leaves a very small contact patch and thus a very poor handling car as the tires wash out and you go into what is known as under steer (push).

The fix to this condition is to increase the distance between the upper and lower ball joints. I do not have the artistic skill required to show this and really needs to be seen to fully understand but roll center is determined by the upper and lower ball joint pivots and upper and lower control arm mounting locations. Roll center is important because it combined with the vehicle center of gravity determine the roll angle. The greater the distance between the roll center height and the c. o. g. , the greater the roll angle. Raising the roll center a few inches above ground is most helpful to neutralizing roll angle. Most muscle cars will have a c.o.g. of somewhere around 18-20”, the front roll center height is around -2”(below ground level) Don’t even get me started on the rear. Since moving the mounting locations is pretty tough to do most people increase the spindle length.

There a few options here, the obvious is to use a “tall” spindle hence the phrase “tall spindle swap”. The draw back is that there is no exact replacement spindle for an “A” body that is taller. What is commonly done is use the closest thing available ie. “B” body or “F” body. These are close but not designed for an “A” body so there are side affects. The steering radius and ratio are both reduced and bump steer increases as these spindles were designed for totally different steering geometry.

The other approach less commonly use is to use ball joints that are taller than stock, this effectively lengthens the spindle with no steering side affects as those parts are untouched.

As linked earlier (in this thread or one of the few others of late) you can easily purchase the upper ball joints with raised pivots. The lowers to the best of my knowledge are only available from SC&C, that may change but for now you got to pay the “new” part price tag. If one were not in a rush it may be worth waiting a few months to see if Howe releases these to other suppliers thus lowering the price tag.

I personally have the typical “tall” spindles right now. It was done out of necessity and will be corrected soon. Given the choice I would not recommend them except in cases of fairgrounds cruisers that are looking for some cheap 12” bling-bling brakes (ILE cross drilled rotors look cool through wheels). There are too many sensible options out there too sacrifice steering (and FRCH doesn’t come up that much with tall spindles) to run them.

I honestly have done my best to describe this in layman’s terms. I’m not an instructor nor do I claim to be an expert in suspension design, just a guy who works on cars for a living and paid extra attention in suspension class as well as did some reading later to understand how things work. Pictures are definitely worth a thousand words in this area. For those who want a better understanding I highly recommend “Chassis Engineering” by Herb Adams. It is the simplest to understand of all the suspension books out there. Lots of pictures too. :D

Originally posted by dennis68:
Speedway offers the same thing for the upper Dennis,
This raised upper ball joint on the speedway site is it the correct part for a 71 elcamino??They don't show a app.listing.Just want to be sure.
And they show a Moog part number for it,K6136.I can get the Moog part at the local parts counter instead of getting from speedway,Correct?
Steve
BTW thanks for the laymans terminology.I does make since.

tight and smooth is where it's at! ;) In my best Barry white voice, "OHHHHH YAAAAAAA"

Steve, not sure and not sure. I would go down to the parts store and have them pull a stock 71 ball joint and a K6136. See if they share the same bolt pattern and taper. Then see if the K6136 is taller than the stocker.

When I did my front end the ball joints required for the Speedway arms have a different taper for the spindle so I had to ream the spindle for fitment.

Onabudget,check out my post on this thread http://www.chevelles.com/forum/ultimatebb.php/topic/7/9114.html

Short answer,the "Speedway" UBJs are truck BJs with a larger mounting flange and bolt pattern and different taper than stock Chevelle. I messed with them a few years ago and realized something better was needed. That`s why I was so excited to work with Howe on direct fit tall stud BJs for muscle cars. smile.gif I really wish they could be cheaper but once you see them and the quality of the machining etc. it`s easy to see why they cost what they do.

For your intended use I`d stay away from poly bushings. I`d recomend 1) checking to see if Moog is offering their HD high durometer bushings for the A body. They`re similar to the bushings used in 1LE Camaros or C5s. Barring that I`d just get *good quality* (ie. Moog or the like) rubber bushings. Same for the rear arms. Steer clear of "discount" bushings or the kits that are very inexpensive and *seem* like a great deal. I`ve seen them wear out in only a couple years. Good ones should last for 20+ and 100K miles.

Currie rear UCAs (they`re a little beefier than Edelbrocks) would be an icing on the cake mod that would help control pinion angle changes when pulling heavy loads and locate the rear a little better laterally for slightly better handling.

Next Moog Cargo Coils in the rear (assuming you don`t want to lower it) and stock BB springs up front cut 1/2 coil.
One of the most important things is a really good set of shocks. Don`t cheap out here! QA1 adj. shocks if you can afford them,if not Bilstein,Koni or Edelbrock IAS in that order IMO. Stock F41 size front and rear bars.

Then drive the car awhile. If you`re happy with it leave it alone (duh ;) ),if it understeers too much (likely) go to a larger rear swaybar. If it oversteers (*very* unlikely) go to a larger front one. Sounds like a cool car. Bet it`s fun to cruise with 6 people on board! smile.gif Marcus