Hi, I am having Mark building me 434 ci SBO.

I have added upgrade to the rear frame and front frame already. No pictures yet of the UMI Performance 3028-R Control Arm and their Shock Tower Brace. I installed.

Also sold the rear cover here and have a Moser Rearend Girdle Cover.

Looking to see if anyone had any experience with Fays2 Watts link. Think of putting one in. Mustang guys are very impressed by it.

http://fays2.net/fays2_watts_link_23_.html

I will need to move the exhaust pipes.

The other thing, is the frame rail from front to back. The car was so clean the body was never removed. Just change the bushing to Ploy-graphite ones.

Is there a way I can beef the rails up. Without lifting the body off to weld steel on?

She drive like a rocket ship on rails. Just the bigger engine.

Any help would be great. Thanks John

 

I have no experience whatsoever with Mustangs, but I can tell you that a Watts link added to an otherwise stock GM rear suspension will bind terribly. The whole point of the angled upper control arms is to locate the rear axle housing laterally as well as fore-aft. The Watts linkage also locates laterally. Using the two together is asking for trouble. The Watts link is used either with ladder bars or with a three-link rear suspension such as was used on the mid-60s Impalas. Does your friend with the Mustang have real, back-to-back track times, or is this just from testing with his butt-G-meter (which is about as accurate as the butt-dyno)?

 

I said Mustang guys, I did not say my friend with a Mustang. Normally my only interaction with Mustang, is passing them and seeing them in my rear view mirror!

From a old fart to another! Sorry! But I hate when people put words in my mouth that I never said!

After some research this morning. I found this.

We run a Fays 2 Watts link on our Open Road Race 2+2. This allows the use of floppy bearing control arms to reduce binding and not worry about the rear tires rubbing the frame or fenders. The courses we run in Nebraska are like paved cowpaths and in some stretches the word paving is being generous.

With conventional bushings and high lateral Gs hitting a bump mid corner could launch the back of the car into the air, because it was bound and the suspension couldn't absorb the hit. With spherical bushings and the fays 2 there is much less drama.

Here is a video of the last corner of the SORC in 2004 when we Slid through the grass @100+ mph. Rear suspension was conventional arms/Herb Adams rear bar.


Next; Here is the full course in 2014 with the Fays 2 rear and a Pro Touring rear bar Much less drama for the same speeds. Fast forward to Weed Wacking Corner above is at 13:30. The pavement is unchanged in 10 years, but by my arguing with my dad, you can tell its no big deal:


Does that help any? Joe

Oh the car is a 1986 Pontiac Grand Prix 2+2

 

Andrew put one in his car... he's been driving it more lately since this post, could talk to him about his experience with it.

https://www.tapatalk.com/groups/real...ts+link#p58458

 

I do not understand!!!
Having been a Oldsmobile guy from the 70's. I have put 100's of hour and alot of money into my 87 Olds. At 61 years old, it's starting to get hard crawling under the car.

Have tried many different things to make my car the best it can be. See my picture in my profile. I have real world knowledge of what works and what did not on my Cutlass.

I have leaned a lifetime of knowledge here from people here. Many who I have a greatest amount of respect for.

But. To ask for help! To see if anyone has experience on a subject, on trying something new and different. To have words put into my mouth that I never said! And than get Butt jokes!

I guess options are sometime like anuses, everybody has one.

 

Thank You! Luke for your constructive help.

John

 

This isn't an uninformed opinion, it's based on an engineering degree and four decades of experience designing structures and mechanisms for aerospace applications.

The factory rear suspension with angled arms is designed to provide both fore-aft and lateral location of the rear axle housing throughout the range of suspension travel. Adding another lateral locating link while keeping the factory arms results in an overconstrained mechanism and WILL cause binding somewhere in the range of motion.

The factory rubber bushings are intended to provide some compliance to trade off handling precision for ride comfort. Yes, this can be improved. The best way to remove this compliance is to use metal spherical bearings at each of the eight bushing locations. This removes all compliance from the bushing locations and positively locates the rear axle. Of course, there will still be deflections in the control arms themselves due to bending that will introduce some small imprecision. You can use tubular arms with improved bending stiffness to mitigate this.

I have no idea what "floppy bearing control arms" described in Post #3 are or how they help. Adding any compliance to the bearings in the control arms results in less precise housing location and thus worse handling.

If you MUST run a Watts linkage, there are a few options for the rear suspension that avoid an overconstrained and binding linkage. You can relocate the stock control arm pivot points so that the rear suspension becomes a parallel four link suspension that ONLY locates the axle fore-aft and then use the Watts linkage to provide positive lateral location. This is a determinate linkage and will not bind. You can change to a Chevy-style three link rear suspension, which will also be determinate. You can convert to ladder bars, which also only provide fore-aft location.

I have no experience with the product you are asking about, nor the background of the person who designed it. I will say that many of the aftermarket suspension components I've seen offered are crap and obviously not designed by anyone with any engineering expertise. They DO serve to increase the seller's profits, however.

 

Joe, believe it or not. As I mention here early. You are one of the many here, who's
knowledge I have the greatest respect for.

That being said. You stated you have engineering degree(PE?)and four decades of experience designing structures and mechanisms for aerospace applications.

But real world testing, can be just as important. And show, just maybe. The engineer did not get it 100% right! Calculation and design prove it. But we just missed something.

Just ask the engineers who worked on Tacoma Narrow Bridge(Galloping Gertie) Three Mile Island, Challenger and Columbia Disasters.... The list go on and on and on throughout history! At least five engineer tried to warn NASA about Challenger.

Yes!, most engineers throughout history, their designs are 100%

Something non-engineers build thing, engineers say will never work. But work perfectly.

No one is 100% right all the time. Alter all we are all human, we error.