Hello all...

Next month I'll be under the car replacing some worn out bushings during a gear change. The car's got a 396/TH400/3.31 posi and I'm going "up" to 3.73's. It has all factory/stock parts now (F41, boxed lowers, 7/8" I think, factory sway bar, worn rubber bushings, etc.). Front end is in great shape with all rubber bushings/links. I strictly drive on the street/cruise, only a few stoplight to stoplight romps against the imports, and only go against the 1320' clock once a year strictly for fun. I planned on installing Edelbrock adjustable upper control arms to allow for a future pinion angle adjustment when needed, but was wondering about BMR's (or anyone else's) rear suspension packages. My goal is to set up the rear for a smooth ride, reasonable cornering, no squeaks, and no wheel hop. My plan, open for discussion, is...

Replacing all worn out rubber bushings with new rubber.
Replacing the differential's upper ear bushings with new rubber.
Replacing the factory upper C/A's with Edelbrock adjustables.
Adding Edelbrock anti-hop bars (offset any potential wheel hop due to the 3.73 gear change).
Replacing the current stock shocks with adjustables (Edelbrock IAS, KYB?).
Replacing the current old coil springs with new replacement Big Block springs.
Replacing current 235/60/R"14" rear tires & wheels with 255/60/R"15" BFG Radial T/A's on repro 15x7 SS wheels with 4 3/8" backspacing (15" wheels are readily available to me, I'd like to keep the 14's up front for the stance).

Questions: Will the addition of Edelbrock anti-hop bars have a negative impact on ride quality/control? Where do they bolt up, anyway? Should I select a different/bigger rear sway bar to compliment my front 1 1/4" bar? Will the 255/60/15x7 combo work/fit, or would I be better off running 245/60/R14's or 15's on all 4 corners?

I've read many different rear combos here, and each has it's own purpose/goal. In addition, I've read many positive things about Global West, UMI's, and BMR's products. My objective (smooth, quiet ride, decent street handling manners) may be different than yours, but I'd like to hear your opinion on this street combo, whether you've got something similar or not. Adjustable pinion angle is a must for a future driveline change. I figured as long as I'm under the car, might as well "...get 'er done!!!" now. I just haven't ordered the stuff yet...waiting for some op/ed. Thanks again gang, as always, ya'll have been great help.

Thats the size tire I have on the rear,255 60 R 15 on 15 x 7 wheels.They would probably look better on 15 x 8's but they fit easy and I went with what I had.On the front I have 225 60 R 15's. IMO I think you should keep 15 inch wheels fr and rear unless you want some real RAKE.

NoDak, all suspension theories derive from the same principles. Increasing anti-squat or adding more/less roll steer and roll stiffness for different intended purposes is more difficult but everyone (OK, everyone with a full understanding of suspension design theory) will agree that the most fundamental aspects include reducing/eliminating bind and removing as much slop from the system as possible. Doing so entails replacing bushings, ball joints and linkage with new parts and basing link/bushing decisions on what will accomplish previously mentioned goals.

Let’s do a little basic tech background for future referral. When discussing front suspension it is important to remember that control arms only need to rotate, any other motion is wasted energy that is detrimental to front handling characteristics. The best possible choice of bushing is Teflon. Many companies use Delrin which is a derivative of Teflon, GW and their Del-a-lum line of bushings for example. Next would be solid steel on steel pivots, although most complain of the increased NVH. I would list rubber next as polyurethane is a better choice initially but over time cold-flow will present a problem as the bushings begin to set in an egg-shape rather than remain round.

Moving to the rear it is important to note that the rear upper and on a much smaller scale lower control arms must move on two planes simultaneously while the axle travels throughout it’s range of motion. From an engineering aspect this is physically impossible which why the system inherently has bind built into it. As the axle moves up and the links pivot in their respective mounts they must “roll” to an extent as the inside and outside distances from mount to mount are different, hence the term “converging four link”. In a simple four link arrangement the links are parallel with the vehicle centerline and as the axle goes moves the links pivot freely with it, albeit with some pinion change but still free movement. The lateral location is of course taken care of by a panhard bar, Watts link or track locator. With a C4L design the objective is to remove as much bind as possible. It nearly possible by adding spherical bearings at every point of movement although NVH would be noticeably increased and then there is that little pinion angle factor. If you eliminate all forms of deflection then as the axle travels pinion angle will have no choice but to change as the lengths of the links do not. With rubber bushings and channel links the links do effectively “grow” as needed to an extent.

Ultimately is up to you to determine how much of a trade off you are willing to compromise. I run the ultimate amount of stiffness and give up the ultimate amount of NVH quality, which in my opinion is not much. Remember that regardless of your intended application the fundamentals are the same, eliminate bind and deflection as much as possible, then tune for intended purpose with geometry changes.

I'm sure I missed some points but after 8 hours on the Little League field I am whooped. Maybe Troy or Marcus will show up and fill in the blanks.

I guess I should answer the direct questions though...I don't care for GW or BMR, they like the "increased stiffness must mean better handling" theroy which a basically a bunch of crap. UMI has a double adjustable pair of links I think. The Edlebrock uppers rock, you would be very happy with them. Wolfe Race Craft has a nice rear suspension package you might want to look into.

Your general combo sounds pretty workable for a basic street machine. Dennis is biased towards carving corners :-) I like carving corners too but I also know from experience that NVH can become a real drag.

The anti-hop bars will raise your rear roll center. This will not affect the ride, but will change cornering response a bit. I would recommend not using a rear anti-roll bar with the anti-hops until you know for sure you can get away with one because it may be too much. The higher rear RC will give you more lateral weight transfer just from weight jacking, and weight transfer reduces traction, so expect the rear to break loose earlier/easier in corners with the anti-hops.

I would stick with 15" rims all around personally. You can get a good rake just using different size tires without overdoing it with different diameter wheels.

All...

71350SS...any pics of your rear 255/60's on the 15x7? Do they look too "ballooned out" for that rim? I was probably going to keep 236/60's on the front, and a 15x8 rear wheel would require a new purchase, and trying to find a trim ring that looks OK without a gap. I can get 4 15x7's locally, excellent condition, and cheaper than new (Wheel Vintiques, etc.).

Dennis68... thanks for taking the time (after a long day) for explaining/answering my questions. I took a peek at your set up, and I would consider changing the factory set up later. Wolfe's package seems alright, but may not be suited for a strictly-street car. I wanted to avoid minor surgery (welding,exhaust relocation) for now as my 396 doesn't turn out high enough torque (yet). If the need arises, I would consider Wolfe's set up at a future date. Any known happy A-body customers? What about keeping my stock boxed lower C/A's with new rubber, factory mounted sway bar, and using Edelbrock adjustable uppers with spherical joints at the diff? A waste of money on "bling" or an incremental upgrade over stock?

Vrooom3440...Thanks for the heads up about the Anti-hop bars. Thought about installing them at the same time as the new upper C/A's for the convenience, but sounds like I won't like what they'll do to cornering. I don't want the rear end kicking/skipping/breaking loose around corners, nor radically changing how the car reacts to my driving.

Thanks for the critique so far, this is the first project I'm taking on in 10 years. The advances the aftermarket has made since I last took stuff apart is incredible. Trying to make a Chevelle a canyon carver 15 years ago was unheard of, and creating dual role cars wasn't done. Now, I feel behind the times and uneducated on mixing and matching components, especially when it comes to steering/suspension geometry. Beer for everyone next road trip...

Forgot...

Anyone interested in Wolfe Race Craft's stuff...

www.wolferacecraft.com

www.wolferacecraft.com/install/abody/abodsway.aspx

for my rear suspension I put what i heard from the site to use and went with the edelbrock uppers and lowers everybody has great things to say about the uppers and once you put the lowers next to the stock stamped control arms you will laugh at the difference! but if you already have a boxed set of originals im sure that a nice new set of bushings (del-a-lum seems to be the prefered) will do the job and give you a little more flex in the arms;the edelbrocks are pretty solid I definetly wasnt graced with the boxed stock lowers so that was my major reason for going with the edelbrock lowers probably cost me more to box the old ones than buying those bolt in edelbrocks i went with stock replacement springs and adjustable shocks once again everybody said good things about the edelbrock shocks and I will probably throw a 7/8 rear sway bar in the rear in the not to distant future to compliment my 1 1/4 in the front and im pretty happy with that setup

69chevelle...

Thanks for the reply. Is Del-a-lum a brand name (like Moog) or a style made by different manufacturers? Never heard of it before.

Del-a-lum is a Delrin lined aluminum bushing made by Global West. If you understand any of the reasons not to use polyurethane in the rear control arms than you will quickly see that Delrin is 10X worse...yes there is something worse than polyurethane in the rear control arms. Where polyurethane is VIRTUALLY void of deflection, Delrin or Teflon is COMPLETELY void of deflection. They are awesome bushings for the front...the worst possible mistake to put in the rear.

Denny...thanks for clearing that up about Del-a-lum. I didn't get the GW connection in your first reply.

REAR HOP BARS DONT ADDRESS THE REAL PROBLEM;GOOD URETHANE BUSHINGS AND THE CORRECT PINION ANGLE WILL KEEP YOUR PINION "NOSE" down and planted w?out ruining the ride

REAR HOP BARS DONT ADDRESS THE REAL PROBLEM;GOOD URETHANE BUSHINGS AND THE CORRECT PINION ANGLE WILL KEEP YOUR PINION "NOSE" down and planted w?out ruining the ride
Obviously a newbie and hasn't felt my wrath for recommending poly bushings in the C4L arrangement yet.....do a search on poly bushings rookie.

Oh, thanks for bringing up the dead thread too.

Obviously a newbie and hasn't felt my wrath for recommending poly bushings in the C4L arrangement yet.....do a search on poly bushings rookie.

Oh, thanks for bringing up the dead thread too.

Ouch... a little harsh don't you think Denny? There are many opinions, some right, some not, but you don't have to be so mean about it. :)

chris

REAR HOP BARS DONT ADDRESS THE REAL PROBLEM;GOOD URETHANE BUSHINGS AND THE CORRECT PINION ANGLE WILL KEEP YOUR PINION "NOSE" down and planted w?out ruining the ride
OMG, now you did it. You went and p***** off Dennis! And you were shouting at the time. Here we go again. :boring:

:p You guys take everything too seriously.

IN CASE YOU DIDN'T HEAR ME, YOU GUYS TAKE EVERYTHING TOO SERIOUSLY.

:p You guys take everything too seriously.

IN CASE YOU DIDN'T HEAR ME, YOU GUYS TAKE EVERYTHING TOO SERIOUSLY.
:waving: I knew that what get you going Dennis. WHAT DID YOU SAY? :D
BTW: I don't take it serious Dennis, it's all good. :thumbsup:

You know, it *never* ceases to amaze me how many times someone will defend something just because Bubba used that setup and thought it was righteous.

Those who have and use their gray matter, rather than just following Bubba, just say no to PU in the rear end.

So you tell 'em Dennis 8-)

Maybe we need a glossary of suspension terms, like what is NVH?
Cheers
Steve

Noise, Vibration and Harshness.

NVH is when you hear your suspension go 'clunk' over a bump.

Actually if you can hear your suspension work, it is NVH. But even more is when you can hear your drivetrain work with it's whines and whirrs, it is NVH.

NVH is a very subjective thing since as we all know some stereos are louder than others ;-)

I am about to pull the trigger on a purchase for 66 rear suspension. This car will never make it to the track but I would like to make a nice street driver out of it. Any advantages to go with the edelbrock adj uppers and lowers over the UMI stuff for my situation. Both companys use poly bushings for the lowers,Would it be difficult to change them out to rubber( What is better than rubber?). Sorry for the stupid question but this is my first project car. I have been doing all the work myself and never have done rear or front suspension.

For the front I am totally confused but things are getting clearer. I think I want to go with the SC&C stage 1 kit but I am confused about brakes and spindal types. What do you guys recommend for to use for the disc conversion. Can I use my drum spindals? Should I stay away from the B spindal conversion. If I went with the Fatman Tall spindal what are my brake choices. Once again excuse my ignorance. I want to purchase all new parts , no junkyard scavengering for me. I have been looking at front brake kits but something seems shady, you only get half the story

I currently have a SBC but next summer aT leat a 500 HP BBC. So I will most likly need to stop

I put the Lakewood Anti-Hop bars on my '66 and it didn't change the ride quality at all.

The only thing they did was completely eliminate the wheel-hop. 100%

Maybe that's just my experience, but I love them. They tuck up nicely so no one can see them and they worked really well for me.

-Curtis Hoovestol