Rear Suspension
 

Wondering where to go with my rear suspension. I auto cross and am going to get into track racing this summer.

There are no threads that I can find comparing a panhard bar to a stiffer sway bar and I am wondering which direction to take. I want to hear opinions from people that have had experiance with either a panhard bar or a heavier rear sway bar. What does each give you?

Idealy I want comments from people that have experimented with both and their pros and cons.

Thanks

panhard > swaybar.

panhard makes the rear so much more predictable it almost is funny. you don't realize how squirrelly the stock watts is either.

Cool! Thats what I was guessing but had never actually heard it.

Anyone else have an opinion?

Don't know if you have seen this, but for your reading enjoyment:

https://www.rx7club.com/showthread.p...ear+suspension

RXDad

I'm not sure if I'm misunderstanding you, but I just want to clarify something. A panhard bar replaces the watts link, not sway bar. It locates the rear axel, and has little to do with roll stiffness. Many people think a well designed watts link is better than a panhard bar, but our stock one doesn't deal well with a lowered chassis.

For auto-x, many people like a stiffer rear sway bar to speed up transitions. I've used the stock set up, no rear bar with the stock front, Re-speed tubular front bar with no rear and with stock rear. I prefer the Re-speed bar with the stock rear.

Road racing I havn't done, but many people say they take off the rear bar to get predictability in long corners.

the stock Watts link has 2 problems, both of which get fixed by a panhard

1. the pivot point or roll center of the stock watts is too high. a panhard is the easy way to lower it. mazda used to have a competition rear axle with a relocated watts too.

2. the stock Watts binds. old hard bushings + multi axis rear axle movement = binding.

on paper i agree a watts is better, but its really easy to do a nice panhard. when you run a panhard that's basically horizontal, and it goes from wheel to wheel, the total side movement is really small.

i also agree with what you say about the rear bar and transitions.

I can't complain about the rear setup.. Yet.. I'm running a ST front bar and no rear bar. Stock shocks and RB springs. Rest be stock.

So the panhard bar helps correct the geometry of the rear end to prevent binding with a lowered car thus giving a more predictable feel to the rear end.

A stiffer rear bar will probably help a bit with understeer and give you better transitions in quick corners.

Can you run a rear bar with a panhard? It seems like they would get in the way of eachother just looking at a picture of a panhard.... I have never actually seen one.

Thanks for clearing up my confusion.

the panhard only changes the roll center and it doesn't bind like the stock watts, so its better, but the bad geometry is the unparallel and short upper suspension links.

i think you can run a rear bar and panhard, i never tried though...

Tri-link + panhard = Happy car


Isaac

Depends on what panhard you run. If you run the Gforce bolt in bar it's next to impossible toi run a sawy bar. On a side not with the drastic change in roll center the car rolls about 1/10th what it did with the watts and a stock sway bar. Best mod ever was ditching the watts and swaybar in favor of the panhard. I'm still running the shitty top links too, I cannot wait to replace those.
WHY ISN'T THIS ARCHIVED?
https://www.rx7club.com/showthread.p...ear+suspension

You ditching the upperlinks for the g-force tri-link?

Probably not. More likely a custom 4 link

In my opinion, you can set the car up pretty darned well for autocross without going to a Tri-link/panhard setup. However, for a high speed road course, I think a Tri-link would be necessary.

I had the chance to drive my car (which does great in autocross) at Road Atlanta. The car was far too nervous and twitchy for a road course, and was downright scary at times. You could actually feel the back end shifting around on the downhill esses.

After experiencing that, I plan to install my Tri-link this year (been sitting on a shelf in the garage for a few years now).



.

/\ Didn't I tell you that years ago. I said you just weren't driving fast enough to have the bind issues, and you got all offended. LOL!

p.s. some auto x's are pretty highspeed. I had some days where I was hitting 90 through a slalom.

p.s.s. I wasn't saying you're car was slow, just that I make decent power and my autoX courses in WA were always pretty huge and fast. I was usually just tenths slower than a SCCA National champion in a Nissan GTR on hoosiers.

:nod: YEP!

When you say track racing it the car is there a specific class you have planed to run? I run spec 7 in scca and we cant change out the watts linkage. ya it can be a handful at times to drive but i think its that much more fun to drive and will make you a better driver. As i have seen before if you can drive the hell out of a pec7 you can drive anything fast for the most part. And its a great feeling when you out run "faster cars" and you tend to get more respect from those who know how much of a handful these things are.

has anyone ever tried relocating the stock watts link mount a few inches up? Lowered car + raised watts link mount should be apprximately correct location... or would they be shortened then>? I haven't looked underneath in a while.

I'm running solosprint this year, and my ass end has been all over the map. I didn't want to start chopping the rear end apart, but I dunno. Whats the best results for the least amount of modification?

Read the thread linked twice above... The problem is the watts is too HIGH and it binds under squat and lift of the rearend.

It wasn't a binding issue. More like slop allowing the rear end to shift around a lot. But yesterday I let the wife drive it, and from the passenger's side you can clearly hear the front wheel bearing groaning. Haven't had a chance to check it out yet, but that could've added to the issue if there's any slop in there. I've never changed out the bushings in the watts either, and I'm not really sure what bushings I've got in the rear links anymore.

Hey, I'll admit it. The 3,000 mile trip I took to the Mitty was my post-crash shakedown run. Clearly she has a few issues, but now I've got all week to address them before the 1st autocross. :)