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mazspeed
10-31-2006, 09:34 PM
I'm looking for a side to side brace for the rear end on a leaf spring set up. Something that keeps the wheels on the rear end from coming out under hard corning. The rear can pitch out a bit and I want something similar to a watts linkage to keep the rear-end in check. Does anyone know of any company that makes something like this for the first gen?

Payton King
11-01-2006, 08:51 AM
on the leafs from Global West. That should solve your problem

fatlife
11-01-2006, 10:41 AM
the spring will still twist a little, he's looking for something like a bolt in panhard kit. I don't have experience with them, but people like david pozzi etc have said that it is something you want to be carefull with because if not done correctly it can easily cause bind in the rear suspension, specifically on leaf spring cars

If your tires are rubbing a little it is probably due to them cambering in a little, putting a panhard etc is not the correct solution to fixing the problem. Wheel size is. However if it was me I would start with the del-a-lums like suggested. that will get you in the right direction. I have them in my car. Using them in the front spring eye pocket does make the ride a little harsher but nothing huge. Also if you are running a rear sway bar you will probably want to ditch it if you go with the del-a-lums

mazspeed
11-02-2006, 10:56 PM
Yes, exactly I was looking for a panhard style system. I was wondering if there was a high quality kit available for this car? Yeah, I figured it should be done correctly and be a good kit to not bind up. Anyone?

fatlife
11-02-2006, 11:03 PM
I'd do the del-a-lum's first, of course unless you just want the panhard for the "go-fast look". How much movement are we talking here? Have you rolled the fender lips yet?

4mm
11-02-2006, 11:04 PM
http://fays2.net/

Is this what you are looking for?

mazspeed
11-03-2006, 12:17 AM
Yeah we shaved the fenders enough, but in hard corning I can feel the rear step out maybe 5/8's of an inch or so, way to much for my taste. That FAYS2 looks like that's the ticket. This works with leafs?
It also looks like it's for mustangs only.
Thanks again guys

fatlife
11-03-2006, 12:33 AM
Y I can feel the rear step out maybe 5/8's of an inch or so
How does one feel this while driving?? What is your current setup? something sounds weird. you can't, well you wouldn't want to go start slapping on suspension pieces that could compromise its performance without througly thinking it out

mazspeed
11-03-2006, 12:40 AM
How does one feel this while driving?? What is your current setup? something sounds weird. you can't, well you wouldn't want to go start slapping on suspension pieces that could compromise its performance without througly thinking it out

Well I used to race cars and I know the "feel of my pants" driving pretty well, and can tell when a car is not doing something it should. I can outright feel the rear end move this small of an amount. Yes you're right, I won't be putting on parts for effect, but I do drive the car aggressively, and can tell when something doesn't feel right. The rear setup is Comp engineering slide a links with Global west leafs with duel adjustable QA1's in the back with a sway bar, which is being replaced with a different kind with more adjustability.

fatlife
11-03-2006, 12:58 AM
Well if I remember those slide-a-links already have solid front bushings. I would still do the rear with the del-a-lums, they are a superior bushing and will also help with lateral deflection. I'm still suprised its moving that mucy, are you sure the feeling you are getting isn't from some kind of odd slid-a-link setting? Too much preload? I would think the rear swaybar would help some, since it would resist bodyroll= less pivoting/less axle side movement

EDIT: also do you still have the rubber bushings between the axle and leaf spring. I would be getting rid of those too.

mazspeed
11-03-2006, 01:19 AM
Well if I remember those slide-a-links already have solid front bushings. I would still do the rear with the del-a-lums, they are a superior bushing and will also help with lateral deflection. I'm still suprised its moving that mucy, are you sure the feeling you are getting isn't from some kind of odd slid-a-link setting? Too much preload? I would think the rear swaybar would help some, since it would resist bodyroll= less pivoting/less axle side movement

EDIT: also do you still have the rubber bushings between the axle and leaf spring. I would be getting rid of those too.
Well a rear end will move that much. There is a lot of areas that can move from the leaf points to the holders (can't remember the name) but there is a lot of play that is typical in these areas under heavy lateral load. The swaybar doesn't help at all for side to side motion. In fact around where the sway bar, there is about an inch on each side where it has itself gone side to side and pealed off the paint, that now has to be repainted.

4mm
11-03-2006, 03:29 AM
FAYS2 looks like that's the ticket. This works with leafs?
It also looks like it's for mustangs only.
Thanks again guys
Look at the first pic on top, it is also made for 67-69 Camaro with leaf springs.

fatlife
11-03-2006, 11:28 AM
Reason I mentioned the sway bar is that it reduces body roll and usually when the body pivots farther from side to side the rearend will step out accordingly, if it rolls less the rearend should not move out as far unless of course I didn't really think that through :lol: what kind of bushings and shackles are you using in the rear leaf spring pockets? I would start by putting in some delalums in the rear along with the heavy duty shackles, and then make sure there are no rubber bushings between the rearend and leafsprings(what you were trying to describe) and then go from there. But if you insist on spending $ and time and addding extra weight go for the watts link.

Steve1968LS2
11-03-2006, 12:01 PM
What about the Camaro bolt-in Watts Link from Fay's-2 Suspension? Oh wait, I see it was already mentioned.

Jim Fay is a good guy and a racer. I would give him a call and pick his brain some on this..

Seems like what you're looking for.

www.fays2.net

Steve1968LS2
11-03-2006, 12:04 PM
Yeah we shaved the fenders enough, but in hard corning I can feel the rear step out maybe 5/8's of an inch or so, way to much for my taste. That FAYS2 looks like that's the ticket. This works with leafs?
It also looks like it's for mustangs only.
Thanks again guys

As mentioned it works with leafs and fits things other than Mustangs like 1st and 2nd gen Camaros :)

fatlife
11-03-2006, 12:30 PM
K.i.s.s


BTW maybe its from hitting too many curbs with the rearend :willy: :lol:

mazspeed
11-03-2006, 04:09 PM
Hey guys I spoke with Jim today. Yes he's a great guy. I'm going to run this setup by the guys at CAR and see what they think, but this looks like the ticket. What I spoke to him about he seemed to know right away what I was talking about. Since the front end is going high end stuff, might as well keep the rear end in check too. I can't wait to drive it (again) :D

Thanks again fellas.

4mm
11-03-2006, 06:01 PM
Good choice, I just put a Fays in my 70 Mustang and will get a chance to drive it next week. :thumbsup:

mazspeed
11-03-2006, 06:23 PM
Good choice, I just put a Fays in my 70 Mustang and will get a chance to drive it next week. :thumbsup:

Let me know if you can feel the difference.

Thanks

fatlife
11-03-2006, 09:24 PM
Since the front end is going high end stuff, might as well keep the rear end in check too.

This doesn't make it any higher end than any other leafspring system.

mazspeed
11-04-2006, 01:31 AM
This doesn't make it any higher end than any other leafspring system.
It does actually.

fatlife
11-04-2006, 10:46 AM
:rolleyes:

mazspeed
11-04-2006, 10:52 AM
:rolleyes:

:drama:

fatlife
11-04-2006, 11:30 AM
:beathorse

mazspeed
11-04-2006, 11:47 AM
I'm curious as too why you think this doesn't improve the rear end?

fatlife
11-04-2006, 12:18 PM
Well since you asked, here is what I'm thinking;
For one I still can't see how you "feel" the rearend moving around under the car. Not saying its not possible but saying that you are an ex race car driver does not make it so(sorry for sounding so blunt). Second it seems that you are looking for something "better" than a leafspring setup and trying to add on more to it to make it "high end"

Have you even thought about the other suggestions? It appears that you are more stuck on buying some new fandangled suspension ad-on that is not even needed just for cool bonus points. Before I went and dropped some coin on something like a watts link that in the end after paying someone to install it is gonna cost you probably $1000 I would be looking at more simple things to actually fix the problem, not just throw fancy parts at it that aren't needed.

There are many racers and people driving leaf spring sprung cars w/o bandaids like panhards and watts links with much success. THere have been threads here and PT.com where suspension engineers state that adding somethingi like this on to a leafspring suspension is NOT a good idea, yes it is doable but it needs to be well thought out. I don't see how the driving your doing is so much different that warrants something like this?

It seemed to me you just wanted to bolt something new on the rear suspension to "seem" better to match the frontend of the car. Like maybe you came up with this whole idea of the rearend shfiting out of thin air to make a good excuse to bolt on a watts link because they look racey. a set of del-alum rear bushings are under $200, and removing the rubber pads from the rearend housing is free. and both of these could easily fix the so-called rearend shifting problem that you think you have.

Its your money and your car(really nice car BTW) and of course do what makes you happy, but if you really just want to fix the problem than I think you should start out with the simple/basic stuff, before you go through your money away on "racey" parts to compete your idea of a "high-end" rear suspension.

do a search on PT and here for info on using these systems on leaf spring cars. I know David Pozzi and Mean69 have a few posts with some good techinical data for you. Sorry I can't provide tech data on why its not a good idea, but I'm no guru :thumbsup: but maybe you can make it work? Not saying that it can't be done, just that you would want to do some research before you shell out the moey.
EDIT:
I just read his tech on his site half-azzed and it seems he thinks that leafspring suspensions can benefit(duh, he's selling them) so maybe he's on to something, but his site does look like one huge ad I'd be a little skeptical. Its been explored previsouly like I stated, but maybe we can get some suspension tech guys to examine what Fay's is claiming and comparing it agains their own opinions. I still stand that you should first attempt to fix the problem with more simple solutions, but I also think that these systems could be explored a little more. I don't have the knowledge to really say whether it will work or not, but only that others who do, have said not to run them :thumbsup:

fatlife
11-04-2006, 12:25 PM
oh, and doesn't that fatman frame use mustang II geometry?

mazspeed
11-04-2006, 12:39 PM
As far as being able to feel what the car is doing, is something I have always been able to do. A lot of guys can feel their car and know what the car might need. The shop that is redoing my car is very experienced in such things and I explained to them my issues with this live axel rear setup. The cars I raced back in the day had a solid rear, but also had a watts link from the factory to control the rear from going back and fourth. Their design was not that great, so you would take it out for a panhard bar that would do the same thing without binding. I have talked to enough suspension experts that have told me that the way I drive, or might drive the car, tells them that a device like this is a good idea. Delum bushings and taking out the rear rubber pads (already done by the way) doesn't help the inherent problem with a live axel rear with no panhard bar or watts linkage to prevent the rear from fighting the front end on hard turns with smooth or rough pavement. I need that rear end to be stable at high speeds. I don't have it with the current setup, that's why I asked if they made anything for the camaro to counter this problem. I can see the problem with my sway bar taking off over 1 inch of paint on either side of the rear end because of the side to side movement. Too me that's a problem, because the rear end is moving during a hard corner. This is not an idea situation for a good handling car. I drove the car for 500 miles, and gave it to CAR and told them that the frame needs to be beefed up, the rear end moves, and the front geometry and shocks were not up to what I wanted. So that's why DSE weld in subframe connectors and extra custom frame braces are going in, a watts link, and a redone front end is also being done along with some other improvements. It's not a "bling" factor, it's a safety and handling factor. BTW I have never seen a race car with just leaf springs and no device to control side to side movement, if there is, they are more then likely weekend racers and not someone looking for every advantage on the track that they can get. I'm looking for every advantage I can get. Believe me, I know what makes a good handling car, I just don't know what's always available for them, that's why I ask..

mazspeed
11-04-2006, 12:40 PM
oh, and doesn't that fatman frame use mustang II geometry?

That's being addressed as well.

fatlife
11-04-2006, 12:43 PM
Okay thats understandable, so the only clue the rearend is moving is from the swaybar and your gut feeling? (the rearend WILL move some, but how much is excessive is the key)

mazspeed
11-04-2006, 12:54 PM
Okay thats understandable, so the only clue the rearend is moving is from the swaybar and your gut feeling? (the rearend WILL move some, but how much is excessive is the key)

All you have to do too move the rear is take and push back and fourth on the car. You can see it go side to side just a little, now image you driving the car at speed and flicking it though corners. 100 times the force of side to side motion. Yes I can feel it, yes the sway bars movement side to side tells me how far it is moving. An inch side to side is not uncommon. The tires during a hard turn on a dip in the turn hit the side of the body slightly, this too is a problem. It's not bottoming out, it's too much lateral movement. This is far from ideal. When you have this kind of movement, you also get camber shifts, this makes it very twitchy at the limit during these shifts of hard corning. No movement is best.

fatlife
11-04-2006, 12:59 PM
Well hopefully someone can chime in with some suspension background and fill us in. Good topic...................although there are still holes in your story :P :D

fatlife
11-04-2006, 01:49 PM
also I went and did your scientific evaluation of lateral runout on my car, only thing that moved was the sidewall of my tire, while pusing violently on the car? But hey, maybe the watts link will be what your looking for. Not many people are using them so maybe you can be our guinea pig :unibrow:

mazspeed
11-04-2006, 02:00 PM
also I went and did your scientific evaluation of lateral runout on my car, only thing that moved was the sidewall of my tire, while pusing violently on the car? But hey, maybe the watts link will be what your looking for. Not many people are using them so maybe you can be our guinea pig :unibrow:

I can get mine to move, but just a wee bit, not a lot. I might have a little more force behind my arms pushing the car. :unibrow:

fatlife
11-04-2006, 02:01 PM
These are both quotes from Mean69 from a differnet site, sorta confirms whats already been said, I still say you try out some differnet bushings in the rear shackle but this is what I found;
A Panhard bar, or Watt's link, is very commonly used with the vintage race cars, and is pretty effective, especially if rubber type bushings are used on the leafs. You won't get any cross talk, or not appreciably, between the vertical motion of the leafs with regard to the PHB. There is a very slight lateral motion as a function of bump with the PHB that can be minimized with a suitably long bar (over 36" is probably fine for a limited amount of vertical travel, but make it as long as you can). In addition, the bar should be parallel to the ground at ride height, and most importantly, the roll center of the PHB should be as close as possible to the roll center height as determined by the leaf springs, or you will get some form of battle/bind = not desireable. The roll center height of a leaf setup, I am 95% certain, is defined by drawing a line through the front and rear leaf bushings (side view). Where this line intersects the axle, vertically, is your RRCH from the leaf standpoint.

I have seen a lot of debate over this for the past several years, and the conclusion I have to draw from all that I have seen is that your car will probably run faster using one, than it will without using one. Virtually ALL of the early Trans Am cars, and a darned good amount of the early B Production cars I have seen that use leafs either use a Panhard, or Watt's to futher locate the axle assembly. The A-sedan Camaro in my shop right now has a Watt's/leaf setup. There must be a reason for it!

The biggest debate comes in the form of defining the roll center. The leaf springs have one, and there would be a second one defined by the PHB/Watt's. If the two aren't matched (and this is nearly impossible in bump/droop), there will be some form of associated bind between the two. One of those things that you look at and scratch your head, until you see a car on track with one that performs really well (or in the case of the vintage races down here two weeks ago "dozens" of them working well).

If it is just a street driven car, I wouldn't bother, but I would go with a set of the available delrin type bushings. If the car is going to spend a good amount of time on the road course, I'd recommend looking into it a bit further. Though not offered as a product, it would be pretty easy to adapt the Watt's we are using on our three link kit for leaf's. There is a commercially available PHB, and Watt's for early Mustangs (Maier Racing, and Fays II, respectively).

fatlife
11-04-2006, 02:04 PM
SO exactly what is your rear setup? springs? spring rates? single or mutli spring? bushings etc? ALso why did you decide to use a rear roll bar?

mazspeed
11-04-2006, 02:09 PM
I have to agree with everything there to a point. Like I said my driving style a properly designed watts link will help with my car. Delrun and no rubber bushings on my leafs doesn't stop the fact that the locating points from each side of both leafs from moving side to side.

mazspeed
11-04-2006, 02:22 PM
SO exactly what is your rear setup? springs? spring rates? single or mutli spring? bushings etc? ALso why did you decide to use a rear roll bar?

Global west springs dearched in the back. A goofy rear swaybay being changed to a lighter adjustable, if not elimated altogether bar. Crappy fatman carrera shocks in front with their 500 lb springs in front with another cheap 1 1/8th swaybar up front. All this is being changed to custom koni hydraulic shocks with rebound and compression controls, with 550 pound eibach springs with geo changes up front and adjustable swaybar up front. Rear will have either the same springs or DSE springs with the same style koni's and a watts link with either no sway bar or an adjstable swaybar. I'm going to drive the car and let them know what I need after that. The car is being corner weighed to spec the front and rear shocks.

The rear bar was added to keep the car flat and not twist as much. They work better on quick turns, but for mountain driving it's better not to have one. The stiffer chassis and watts link should more then make up for the use of a rear bar on a short track and should be much better on a long fast section. Again it's one of those trial and error type of things that I will know more when I drive it.
I'm not too sure about spring rates in the rear, but I have heard that DSE's are a tad softer. I would like a little harder suspension car then a softer one.

fatlife
11-04-2006, 08:47 PM
Well I hope you run this all by someone a little wiser than both of us. I already see some descrapancies in some of the things that you state. I'm suprised no one else has jumped in this thread, what happened to any of the tech here? Everyones so excited about show cars and sema, no one can help out?

mazspeed
11-04-2006, 11:50 PM
I already see some descrapancies in some of the things that you state.

What do you mean?

fatlife
11-05-2006, 12:12 AM
Look I don't want to turn this into an argument, but theres just a few things that raised some flags. All I'm saying is that I (as in my opinion) would talk/do some more research before calling it a plan, however I'm the type to triple check most of my decisions. I don't expect you to listen to me %100 but that maybe I would raise some points that would maybe get you to think about it. I'm not saying there is a right or wrong, just that it is a modification worth looking into before making any decisions

The more I read into these the more I keep seeing more advice that is for it. I do distinctly remember people like David Pozzi and such saying that it was not necessary/ and can be very tricky to get right and not have any downsides. From what it sounds like, you could use one just to keep your tires from rubbing. I don't think that it will be so signifigant that it will really be all that much of an upgrade besides the tire rubbing issue. I have my tires pretty far out and didn't have any rubbing issues with my del-a-lums in hard turns for the short time I drove my car. But obviously everyones is different.

You have global west leaves, slide-allinks- and soon to be Watts link. Sounds a little overcomplicated and from the surface appears you are just throwing a lot of parts at it hoping to get something better than a leafspring suspension. You seem pretty set in your ways and already have all the answers so I hope it works out for you :cool: If you decide to pull the trigger, please report back it may be a good solution to a problem that some people might be having :thumbsup:

mazspeed
11-05-2006, 01:20 AM
Don't worry, I'm not here to argue. It's counter productive. I fully understand what you are saying, and of course I will be asking the people involved in the car, their advice as well. They said for me to look at these options, and they do build very fast cars and top notch cars so I will listen to them. They did say that a good setup watts link is a good idea, so I will run this system by them, but the trans am racers that I have talked to (2 of them) said that this is the best fix for my problem, but it has nothing to do with tire rubbing, well not really, but it has to do with keeping the tires planted firmly on the ground. If we were setting up a first gen rx-7 I might be set in my ways, but this is an entirely different car, so I need the advice. That's why I asked. I can tell by set of the pants driving what my cars need, and set them up to my driving style. No harm no foul. This is not a money issue.

fatlife
11-05-2006, 03:33 AM
well thats all good, if CARS says to use it I would trust them(although were they the ones that set you up with that fatman frame??) I'm a little dissapointed though that people are too busy talking about Sema and aren't posting anything in the tech forums. I can admit I don't know enough to say whether it will work or not, but i have seen enough posts that would make me question it. And hey, I didn't think you wanted to argue so its all good :thumbsup:, just knowing myself I didn't want to start one! :D

mazspeed
11-05-2006, 04:07 AM
well thats all good, if CARS says to use it I would trust them(although were they the ones that set you up with that fatman frame??) I'm a little dissapointed though that people are too busy talking about Sema and aren't posting anything in the tech forums. I can admit I don't know enough to say whether it will work or not, but i have seen enough posts that would make me question it. And hey, I didn't think you wanted to argue so its all good :thumbsup:, just knowing myself I didn't want to start one! :D

CAR is a good shop. Matt from matt's bowties suggested the frame. Everyone else hated the frame, but at the time, new to the hobby I didn't know any better about it, but time was not on my side, and if I knew now I would have went for CAR's subframe. Oh well. We will make the best of it. Gearhead really hated it because they were building it.

fatlife
11-05-2006, 11:52 AM
yeah, I've never heard anything but good things about CARS, matt at bowtie classics is sorta a streetrod type of guy. I'm not suprised he recommended that frame, he probably got a good percentage out of it. All the fatman stuff I have ran across is for looks not performance, but I'm sure you can make it work, its a done deal and I wouldn't worry about it too much. Its hard to get good advice, except for here of course.

68protouring454
11-05-2006, 12:41 PM
:beathorse
tell us how everything turns out once they are done with it. when do you think it will be done?

mazspeed
11-05-2006, 01:33 PM
Yeah Ill let you guys know. It should be done in December. By then I'm sure Ill have other changes :wow:

mazspeed
11-17-2006, 09:29 PM
Well we tried to fit the Watts link in today. It's a big time no go. Poor design, was not built for an Aluminum rear carrier on the rear of the 12 bolt. Anyone have any other ideas of a better watts link or a Panhard bar?