I know what the purpose is just thinking that it may not be the best route to take.The panhard bar moves the rear end from side to side every time the rear travels up and down.When I draged raced we used a track locater bar with good results.It fastens to the front of one ladder bar or 4 link bar and runs to the rear of the bar on the other side.Mine ran under the driveshaft and traveled the same so they never hit.It is also adjustable to move the rear end side to side for squareing it.Not a big deal I was just wondering. Thanks Joe
Yes, it does make the rear axle move in an arc, but the idea is to use a long arm and locate it properly so that undesirable arc movement is minimized. All suspension designs are a compromise based on what is a priority - ride, low speed handling, high speed handling, drag racing, etc.
I'll just say this-The stiffer, and less travel your rear suspension has, the less you have to worry about. Also, the shorter the panhard bar, the worse it is. There's many cars out there with them, but I do think a track locater may(?) be better. Then there's an issue with ability to "roll" or for the suspension to articulate around corners. If it's just a driver, don't over think it. Let the games begin
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Cracker head your on, Let the games begin! Sorry V8 Bake but what you call a track locater bar is just another version of a panard rod. You just changed the mounting plane from a vertical mount (Panard rod) to a horizontal mount plane(track locater). .
If I'm reading it correctly, the track bar does NOT mount one end on the frame and the Panhard bar does. I disagree with your saying one is another version of the other Also, they're both "basically" horizontal. One left to right (Panhard), while the other (track bar) sorta fore and aft. But both horizontal. Or I AM reading this wrong
I use space beams (tm) to locate my rear end. They are by-products of the flux extrusion device (tm). Its mounted on the 4th parallel located beyond X = ±infinity. Oh, wait, maybe I just drink too much! Damnit! Sorry I couldnt help you with anything useful other than a little humor.
Whatever works for you! I bet your version can still move the rear end in some direction that would be a problem. Choose your use or track and then choose the most suitable method to keep you on the bitumen. Watts linkage seem the best solution, buy hey they look shocking from the rear and can be difficult fit in some circumstances. A real long and level panhard rod should work fine on streets. A track locator should be OK if it fits your purpose and probably works best in a straight line on a drag strip but probably less useful to most hot rodders.
The track loacter will not allow the chassis to roll like the panhard bar will. Any time the chassis tries to roll, the diagonal link will go into a bind. That's why they are only used on drag and pro street cars. We don't figure those cars are going to be seeing much side load anyway.
Running a track locater on the street means that all side-thrust suspension loads are carried by the front bushings. A lot of stress on the bushings due to leverage as well as bending forces on ladder bars and the like. Ok for drag racing and it's need for very light weight construction, but not a good idea on the street.
Sway bars control the amount of chassis roll. Split bones, ladder bars, and track locator type devices bind up and lock the suspension; allowing little or no roll. You're generating the same side force either way, so if the suspension binds, it's going to lift the inside tire and lose traction. Again, it's all relative to the amount of side force you're generating... If you're on relatively skinny, hard tires; you probably won't see any difference.
parallel link setups need a watts link to "have it all" plain and simple. Panhard bars do the job, and hell....do a damn good job if done correctly. Rear suspension i'd venture to say is one thing a TON (read: metric shit ton x100) of people do ass backwards. So mor than likely if your doing it at home, its wrong in the first place lol. Just read up on shit before you start.
Very good point! As I am going to come up with a 4 link suspension, with an offset carrier housing (not IRS), which needs to fit in a very tight place, I will definitely do my homework. The Panhard bar, is it the same as track bar, which goes from frame to opposite side of axle housing? What are the differences, sound very similar.
Watts link is the best, however, a sliding wishbone will also work if you are tight for space, has no effect on roll stiffness, and doesn't bind. You can make then pretty small, or have them facing front or back, and they will still function. When making a pro street type of car that will be driven a lot with a 4 link, this is what we used. Rides better with no binding. They do, however, need some maintainance (keeping them greased) and they can be noisy (will clunk) if there is too much play. We used a teflon insert inside the wishbone that required no grease and kept it quiet, but tended to wear out if the car was street driven a lot. You had to replace the insert every couple of years. If they went with ladder bars - a track locator was preferred. Its hard to put a long panhard bar in there with the ladder bars and springs, minitubing, so you get stick with a short one and the arc of motion gets pretty big. It makes the car want to jump to the side when power is applied and the suspension reacts.
IMO, a Watts Linkage is the perfect lateral locating device, followed closely by a long Panhard Rod or a Jacobs Ladder. The side shift on a 30" long Panhard Rod at 6º of suspension travel (~3" up or down) is ~3/16". You'll never feel that, and neither will the rest of the suspension system. So long as you mount the pivots at the same elevation on both ends, the handling will not change with the turn direction, as the roll center will only move up or down ~3/32" through the whole suspension travel. As my old man would say, "We're talking fiiiiiiiine little points here, and we ain't buildin' a piano."
I have already put triangulated 4 link in the sedan,whitch I think is the best anyway.I just wanted to know what every one else thought about a panhard since it is the last thing I would use.Hope this hasnt chaffed any one.Some people love them and get along great with them.I think a watts link or wish bone are all better than a panhard.
I think Watts linkage systems are ugly. Wishbones work but are better suited to big tire cars. As stated above about 3/16 side to side...well that's from full up, or full drop out, to total collapse. When does that ever happen? Maybe on a TV chase scene. Anti-roll bars...we DO know how they work, right? I think it's time to add a HAMB road race event to go along with the HAMB DRAGS. OK I was being a tad of a synic. Don't over think this shit.
Does this sliding wishbone work similar to a Dedion setup? Where, how and what effects it's roll center if so? Ya got a picture of one of yours? Please.
Looks like this: Roll center height is the mounting height of the front heim. This is NOT a triangulated 4 link. There are still 4 longitudinal links to locate the axle and pinion angle.
It happens on race cars pretty regular like. Our dirt modified had 9" total rear travel, and it was not at all uncommon to bottom the shock in both directions, on both sides, if the track was very rough at all, like say when we had to run with sprint cars for instance. I love to watch 'em, but I sure hate to share a race track with 'em. The long bars don't swing the housing much side to side, but on the dirt we ran short J-Bars. They offset the roll center to the left, and let us get up on top of the bar as the car rolled over (gotta love mechanical side bite). The setup works very well when it works, but it's twitchy as hell when it don't.
V8 Bake, You really haven't stated what you were building so much of this is speculation but if you have installed a triangulated 4 bar you don't need an additional control rod to locate the rear. With a traditional T 4 B set up the upper control arms point to the center, this positioning is the simplest way to center the axle. What benefits a T4B ride is a sway bar. Now to answer Grouchos question: Any chassis has to be examined in three platforms. There is the horizontal (wheel base), lateral (wheel track) and then a rotational aspect (turning). -X- In the case of axle locating the difference between a panard rod and what drag racers term track rod is that the panard rod is mounted to correspond with the lateral component control. The track rod performs the same function but on the horizontal plane . The are both attached to a fixed point on the chassis and lengthening or shortening the rod can be used to locate the desired component. The advantage of a panard rod is that it will fit in a more confined area and that it will withstand higher lateral load forces during severe cornering. An advantage of using a track rod with a coil suspended vehicle in drag racing is that the bracketry has a secondary purpose as its positioning controls the gear torque (axle wrap) of the rear axle upon acceleration therefore creating a straighter launch. The disadvantage is that because of its lower mounting position it looses ground clearance and because of its angular mounting it is not well receptive of higher side loads under severe cornering. Coolhand, if your car wont go thru the bumps it is because you have too much RR weight transfer for the track or the track crew did a lousy job of preparation. Its the little tires that cut the track up.
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