Sway bar vs air bag

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Sway bar vs air bag

Postby Silverback » Thu Aug 10, 2006 4:42 am

It’s a fairly simple question which I’m not sure has a simple answer… in a drag racing situation, what is the functional difference with preloading the suspension with an air bag vs an adjustable sway bar?

(FWIW, the car in question is an firebird with a sliding link torque arm rear suspension and although the drivetrain should be capable of nines the ability to return it back to “handling”/street settings quickly is important)
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awesomebill

Re: Sway bar vs air bag

Postby awesomebill » Thu Aug 10, 2006 6:16 am

Silverback wrote:It’s a fairly simple question which I’m not sure has a simple answer… in a drag racing situation, what is the functional difference with preloading the suspension with an air bag vs an adjustable sway bar?

(FWIW, the car in question is an firebird with a sliding link torque arm rear suspension and although the drivetrain should be capable of nines the ability to return it back to “handling”/street settings quickly is important)


It really does not matter which you choose, both of them help keep the rrw on the ground when the power is applied. the question should be why is it needed to keep the car from twisting? Answer this one and you will see. My opinion is keep the stock sway bar for the front and rear and you will see a perfect launching car even into the 8 second zone. Only gets better with stiffer sway bars for more torque engine, tighter converter, higher gear ratio for shorter tires to run these classes with short tires and over 170 mph. Think about it for a while and you'll get it.

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Re: Sway bar vs air bag

Postby Silverback » Fri Aug 11, 2006 1:24 am

Huh, you were one of the people that I was hoping was going to reply, but to be honest I was execting a totally different answer from you.

awesomebill wrote:It really does not matter which you choose, both of them help keep the rrw on the ground when the power is applied.

Huh… OK, in both the chevelle thread and the 4 link thread you (and I think at least one other in the 4link thread) alluded to the sway bar being superior to the air bags but never said why. That seems to be the opinion of most serious chassis builders, drag racers… where air bags are much cheaper, easier to install and easier to change settings and tune, which only leaves that either the sway bar actually works better or that it’s a myth. If it was just chassis builders I’d somewhat believe that they’d recommend an adjustable bar over bags because that is more along the lines of what they do…

the question should be why is it needed to keep the car from twisting? Answer this one and you will see.


Trick question? To counter the torque reaction the the engine torque being applied to the rear gear… in a perfect world that could be done with geometry but being that I intend to use the car for other use then dedicated drag car I don’t know that there is a geometry change that would work well with the TA susepension and not mess up handling at the same time.

My opinion is keep the stock sway bar for the front and rear and you will see a perfect launching car even into the 8 second zone.


Huh, you know, I’m the only one that I know that has been running front and rear bars on the car thus far, and in general I’m fairly happy with how it has been working at lower power levels. I figured that if/when I ever get the thing running again the obvious thing to try with more power is to disconnect or remove the front bar to get more reaction from the front suspension and potentially more traction, but I figured that will also result in needing more control over what the rear suspension actually does side to side.

Only gets better with stiffer sway bars for more torque engine, tighter converter, higher gear ratio for shorter tires to run these classes with short tires and over 170 mph. Think about it for a while and you'll get it.


I think that you lost me here…
Mark
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awesomebill

Re: Sway bar vs air bag

Postby awesomebill » Fri Aug 11, 2006 5:42 am

Silverback wrote:Huh, you were one of the people that I was hoping was going to reply, but to be honest I was execting a totally different answer from you.

awesomebill wrote:It really does not matter which you choose, both of them help keep the rrw on the ground when the power is applied.

Huh… OK, in both the chevelle thread and the 4 link thread you (and I think at least one other in the 4link thread) alluded to the sway bar being superior to the air bags but never said why. That seems to be the opinion of most serious chassis builders, drag racers… where air bags are much cheaper, easier to install and easier to change settings and tune, which only leaves that either the sway bar actually works better or that it’s a myth. If it was just chassis builders I’d somewhat believe that they’d recommend an adjustable bar over bags because that is more along the lines of what they do…

the question should be why is it needed to keep the car from twisting? Answer this one and you will see.


Trick question? To counter the torque reaction the the engine torque being applied to the rear gear… in a perfect world that could be done with geometry but being that I intend to use the car for other use then dedicated drag car I don’t know that there is a geometry change that would work well with the TA susepension and not mess up handling at the same time.

My opinion is keep the stock sway bar for the front and rear and you will see a perfect launching car even into the 8 second zone.


Huh, you know, I’m the only one that I know that has been running front and rear bars on the car thus far, and in general I’m fairly happy with how it has been working at lower power levels. I figured that if/when I ever get the thing running again the obvious thing to try with more power is to disconnect or remove the front bar to get more reaction from the front suspension and potentially more traction, but I figured that will also result in needing more control over what the rear suspension actually does side to side.

Only gets better with stiffer sway bars for more torque engine, tighter converter, higher gear ratio for shorter tires to run these classes with short tires and over 170 mph. Think about it for a while and you'll get it.


I think that you lost me here…


The only reason for running an air bag is quick and easy and very inexpensive. These are very dangerous also. Lines to be pinched or rubbed a hole in, air bag burst on a de excell and the car go out of control etc. What goes fast has to slow down faster. When more air pressure is used to correct the hit, the same weight is also a factor in slowing down. Seen it hundred times. Car go into a wiggle at the big end when the throttle is closed.
As far as the front and rear sway bar, these are very easily installed and have nothing to do with front travel weight being transfer, just keeping it from being transferred more evenly. Same with the rear twist in the rear. I know about the sway bar affect when you take the front on off. It does not work with cars with power even into the 10.00 second area. This will cause the Lf wheel to lift way further than the Rf. If you like the Mr. Twister look than take both off and watch the rr wheel disappear into the rear quarter panel. There are other forces happening only when the throttle is applied and lesson after the car gets moving. Most people over look this and put a bandaid anti roll baron after they had a perfect sway bar for both f&r. Very costly and takes a lot of time. It is o.k. to do but so is your stock front and rear sway bars. I run a 68 Chevelle stock suspension car and used it with and without the sway bar for a test. I removed both and the car was so far out of control, I had to lift and get back in a few times until the car was out well past the 300 ft. I reinstalled the sway bars and could bring the NOS in at the hit and the car would drag the bumper and be dead straight. I was only allowed to run the car to the 10.00 zone because it was only legal for that because of the unwillingness to wreck a nice 68 so the 6 point was all I would put in my real street car.

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Postby BillyShope » Sat Aug 12, 2006 2:47 pm

Whether in traction or in cornering, a tire pair performs best when equally loaded. Unfortunately, driveshaft torque, with a beam axle car, tends to unload the right rear. If all of your car's roll stiffness was at the rear, the reaction to the driveshaft torque would feed back to the rear axle assembly and the tires would remain equally loaded. But, the driveshaft torque reaction is distributed...front to rear...in proportion to the relative roll stiffness. If, for instance, 60% of the roll stiffness is at the front, only 40% is fed back to the rear axle assembly. So, 60% of the the driveshaft torque is acting to cause problems with rear tire loading.

Both the air bag and the adjustable sway bar can be used to provide a static preload, but the adjustable sway bar is superior IF it also appreciably increases the rear roll stiffness.

There is no excuse for retaining the front sway bar in dragracing applications. This only adds to the problem of unequal tire loading at the rear.

Ed-vancedEngines

Postby Ed-vancedEngines » Sat Aug 12, 2006 3:21 pm

You mentioned you have a FireBird. Is it a 3rd or 4th generation car?
Big difference in the factory setup and rear to front weight distribution on both of these.

I will depart from the normal (What's new lol) and will tell you something that will be fairly simple and inexpensive but will work.

You mentioned that you have the sliding link torque arm. If it is factory, ditch it. t is designed to flex and to twist. Also the transmission mouted torque arms are good for tearing loose the transmission mount.

There are many aftermarket torque arms on the market and most are similar in the way they perform but are different in appearance. You do not want a direct bolt on factory replacement with same dimensions as is made by many suppliers.

Wolfe Racecraft makes a good one but it is almost identical to the one made by Steve Spohn at a much higher cost.

Steve Spohn makes the best torque arm and suspension parts for the F body 3rd and 4th generation cars that I have seen or used. I like to use his 4th generation bar in the 3rd generation car. It is shorter, and to make the front mount to be more adjustable as well as making the front supporting crossmember to also be with an up and down mounting position adjustment. That way I can easily change the point of Instant Center to higher or lower as needed. He makes his bars with many different capabilites too. I like to get them custom made to my specs and use them a little different though. Steve also races his own 3rd gen Camaro using only his suspension components as a test bed. I do also like his adjustable bottom bars or you might call them control arms for the rear. If it is street by all means use the polyurethane bushed ones.

This torque arm is exerting the lifting force near the center of left to right balance of the car with driver inside so it does work pretty good. He and others also do offer a rear bracket for the lower rear suspension control arms that will lower the rear of the control arm bars to also cause a change in the combined torque arm-rear control arm bar connection of an instant center.

In some ways that car's rear suspension is different from what we think of in rear suspension adjustment and placement of the mounting of components but in actuality it is still using the same laws of physics to direct the torque force to the rear tires. It is just done differently.

I also do suggest on that particualr car to be used in both drag racing and for street to keep the front sway bar but I suggest to use a spacer between the mounts and the frame to allow it more front rise.

That car can also benefit some from the adjustable anti-roll bar but the factory anti-roll bar also helps better than none.

I have been guilty of using air bags in right rear but do not suggest it for most cars. I hate air shocks in any drag car. I do like to pre-load the right rear and the left front spring some. I guess I am still stuck in old school about that.

That car with the right bolt on suspension parts is a wonderful car to race in factory suspension classes.

Also steve makes an adjustable replacement coil over style front shock for it.

I also prefer either the Spohn or the Kenny Brown supframe connectors for that style of car. For street or strip or just cruising the subframe connectors make a huge difference.

Ed

Steve Spohn
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David Wolfe
http://www.wolferacecraft.com/

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Postby TORQUE INC » Sun Aug 13, 2006 3:45 pm

If im reading this right were talking about a antiroll bar that limits body roll but allows the suspension to work as it should.

Sounds about right.

there are some pretty quick 3rd and 4th gen cars out there.


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Postby Silverback » Wed Aug 16, 2006 4:25 am

Ok, I reread this like 10x before I made any sense of it (AB, somehow your typos were in just the right pattern that I couldn’t make any sense of what you wrote till I was in just the right mood, not sure what that means but it did throw me for a loop). and I’ve come to the conclusion that I had a much better handle on this and what I thought you guys were going to say before I asked, nutshell:

Awesomebill: airbags are dangerous and aftermarket bars are a waste of time, run stock or stiffer front and rear bars (I have 36mm hollow front and 24mm solid rear on it now, stiffer then I actually like on it now)

BillyShope: there is never a reason to run a front swaybar on the street (it’s not that heavy, the hollow one is 13lbs with hardware) and only said that the adjustable rear bar is superior IF it appreciably increases rear roll stiffness (not sure what else it would do)

Ed-vancedEngines: Don’t worry about all this just get an aftermarket TA…

Huh… OK, none of this really agrees with each other or with the stuff that you guys have written in the previous suspension threads, which I find somewhat confusing. I could have sworn one of you (I was pretty sure that it was AB…) wrote something along the lines earlier that the only great way to prevent twisting issues coming off the line is to have as little roll stiffness in the front and as much as possible in the back so the front has as little effect on this as possible to prevent from upsetting the back once the front comes up. Instinctively, after having tried both with a front sway bar and without when the car was running slower (11’s @120), I found that disconnecting my front bar did nothing for my 60’ times, it really doesn’t seem to do anything for the launch but allow the front driver’s side to lift more aggressively.

Ed-vancedEngines wrote:You mentioned you have a FireBird. Is it a 3rd or 4th generation car?
Big difference in the factory setup and rear to front weight distribution on both of these.


I actually have 3rd and 4th gens that see the track, but the car in question is a 3rd gen (87) formula.

You mentioned that you have the sliding link torque arm. If it is factory, ditch it. t is designed to flex and to twist. Also the transmission mouted torque arms are good for tearing loose the transmission mount.

There are many aftermarket torque arms on the market and most are similar in the way they perform but are different in appearance. You do not want a direct bolt on factory replacement with same dimensions as is made by many suppliers.


Not a problem… the car is using a 4L80e for a transmission which is way too big and in the wrong place to use a factory style mount. I’ve been debating if I’m going to make the new mount hang off the back of the tranny crossembmber (with some extra floor pan bracing, don’t like how most of the aftermarket stuff cantelevers stuff off the back of the stock points on the 3rd gen designs, I've seen the spohn stuff tear 3 or 4 front subframe rails now) or if I’m going to add some sort of crossmember (prefer not to for clearance issues).

Wolfe Racecraft makes a good one but it is almost identical to the one made by Steve Spohn at a much higher cost.

Steve Spohn makes the best torque arm and suspension parts for the F body 3rd and 4th generation cars that I have seen or used.


Honestly, I see an artistry in Wolfe’s designs… Spohn, well his stuff rubs me the wrong way, I have a bunch of it that I took off one of the cars and have hanging on the wall in the garage. In general the spohn stuff appears to be under engineered and overbuilt. Usually it doesn’t break but is often many times heavier then it needs to be (his adjustable control arms are a little over 2x the weight of a set of stockers boxed with 1/8” plate and either will work in a 9 second car)

I like to use his 4th generation bar in the 3rd generation car. It is shorter, and to make the front mount to be more adjustable as well as making the front supporting crossmember to also be with an up and down mounting position adjustment. That way I can easily change the point of Instant Center to higher or lower as needed. He makes his bars with many different capabilites too. I like to get them custom made to my specs and use them a little different though.


Can you give details/pictures? Which style bar are you starting with. I know a number of people that have had issues with his sliding link design and in general like BMR and wolf’s (as well as GW but they are in a different category) designs better, although I haven’t sufficiently satisfied myself that a pivoting front link works the same as a sliding front link. How are you mounting the 4th gen assembly in a 3rd gen (most of the 4th gen assemblies tie into the g-load brace area of the 4th gens where the 3rd gens have nothing there but sheetmetal, I know that the jegster TA has a large, ~1/8” thick contoured plate that bolts into that area and they bolt their front pivot to that)

This torque arm is exerting the lifting force near the center of left to right balance of the car with driver inside so it does work pretty good. He and others also do offer a rear bracket for the lower rear suspension control arms that will lower the rear of the control arm bars to also cause a change in the combined torque arm-rear control arm bar connection of an instant center.


I have a set of his relocation brackets on my 4th gen WS6 (6 speed car) and have found that the suspension hits the tires too hard with them, it will hook hard off the line then a few feet out the back tires literally hit the ground so hard that they bounce and you loose traction (somewhere I have video of this), so I have them mounted back in the stock pivots. On the 1-2 shift there isn’t as much torque available and they actually do help there, but I’ve found that overall on that car I lost more a few feet off the line then I gained by totally eliminating any chirp/spin on the 1-2 shift.

In some ways that car's rear suspension is different from what we think of in rear suspension adjustment and placement of the mounting of components but in actuality it is still using the same laws of physics to direct the torque force to the rear tires. It is just done differently.

I also do suggest on that particualr car to be used in both drag racing and for street to keep the front sway bar but I suggest to use a spacer between the mounts and the frame to allow it more front rise.


That makes sense (I’ve been meaning to do it but never actually got around to trying it) and easy enough to do since I’ve been reproducing TTA front sway bar mounts since they’re not made by GM anymore an I seem to know way too many TTA owners, they spaced the sway bar down roughly an 1” to clear the intercooler on that car.

I have been guilty of using air bags in right rear but do not suggest it for most cars. I hate air shocks in any drag car. I do like to pre-load the right rear and the left front spring some. I guess I am still stuck in old school about that.


I’m with you there… air shocks are a disaster in a performance application. OTOH, I’ve run air bags on my WS6 with good luck, but part of it is that I like stiffer rear spring rates at the dragstrip then I like in a handling situation so I end up running 5-8lbs in the driver’s side (which makes a suprising difference) and usually >20lbs in the passenger side.

That car with the right bolt on suspension parts is a wonderful car to race in factory suspension classes.


I agree and the fact is that you can get good straight line and handling out of it with very minor changes, I’m just trying to figure out how to tweak the straight line as much as possible now since the new engine combo will test that very hard.

Also steve makes an adjustable replacement coil over style front shock for it.


There’s a few designs out there for 3rd gens, none of which I would run, they all have insufficient top mounts which eventually mess up the tops of the strut towers. The 4th gen design is different in that way, the front suspension is basically a coil over from the factory.
Mark
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awesomebill

Re: Sway bar vs air bag

Postby awesomebill » Wed Aug 16, 2006 5:55 am

I never said anti roll bars were not needed. What I did say was you already have an anti roll bar on the front and back of most of these cars. If you remove either when real power is applied, this will allow body roll and unloading of the r/r tire.

The l/r tire gets a free plant every time the pinion trys to climb the ring gear and only gets worst with weight, torque and higher gear ratios. Anti roll bars, just in the rear will fix just about any chassis cars problems.

The problems are with 4 link suspensions, you have now got 2 intersection points that seem not to bothered with each other. This debate goes on in pro stock today.

I like an antiroll bar install for older cars and pro street high nitrous cars where different loads can be placed on the suspension. This will cure all instead of having to preload the r/r when ever you raise the NOS level of power.

People seem to think the car will react to a 100 shot of nos and go straight and then try to hit it with 300 with the same chassis set up. This does not work without an anti roll bar. Different torue loads help lift and plant both tires oppositly. Think about it.

Awesomebill: airbags are dangerous and aftermarket bars are a waste of time, run stock or stiffer front and rear bars (I have 36mm hollow front and 24mm solid rear on it now, stiffer then I actually like on it now)
Last edited by awesomebill on Sun Aug 20, 2006 9:55 am, edited 1 time in total.

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Postby BillyShope » Wed Aug 16, 2006 6:36 am

Silverback wrote:
BillyShope: there is never a reason to run a front swaybar on the street (it’s not that heavy, the hollow one is 13lbs with hardware) and only said that the adjustable rear bar is superior IF it appreciably increases rear roll stiffness (not sure what else it would do)



Having trouble understanding this. Are you saying that a front swaybar should not be used on the street? I couldn't agree with that. Usually, it's a simple matter to disconnect one end while at the strip.

There seems to be some confusion as to the effects of roll stiffness on distribution of the driveshaft torque. Suppose the front of the car was totally solid; no suspension at all. Since there could be no deflection of the rear springs, all of the reaction to the driveshaft torque would have to be taken at the front and, at the other end of the driveshaft, unloading of the right rear tire would be severe. Similarly, if the suspension was returned to the front and the rear was made to be totally solid, all of the reaction torque would be taken at the rear. In the latter case, the rear tire loading would remain equal during launch.

Actually, of course, neither front nor rear roll stiffness is infinite and the reaction to the driveshaft torque is distributed...front to rear...in proportion to the relative roll stiffness. So, by decreasing the front roll stiffness...relative to the rear...we are approaching the ideal of equal rear tire loading.

awesomebill

Postby awesomebill » Sun Aug 20, 2006 10:03 am

BillyShope wrote:
Silverback wrote:
BillyShope: there is never a reason to run a front swaybar on the street (it’s not that heavy, the hollow one is 13lbs with hardware) and only said that the adjustable rear bar is superior IF it appreciably increases rear roll stiffness (not sure what else it would do)



Having trouble understanding this. Are you saying that a front swaybar should not be used on the street? I couldn't agree with that. Usually, it's a simple matter to disconnect one end while at the strip.

There seems to be some confusion as to the effects of roll stiffness on distribution of the driveshaft torque. Suppose the front of the car was totally solid; no suspension at all. Since there could be no deflection of the rear springs, all of the reaction to the driveshaft torque would have to be taken at the front and, at the other end of the driveshaft, unloading of the right rear tire would be severe. Similarly, if the suspension was returned to the front and the rear was made to be totally solid, all of the reaction torque would be taken at the rear. In the latter case, the rear tire loading would remain equal during launch.

Actually, of course, neither front nor rear roll stiffness is infinite and the reaction to the driveshaft torque is distributed...front to rear...in proportion to the relative roll stiffness. So, by decreasing the front roll stiffness...relative to the rear...we are approaching the ideal of equal rear tire loading.


I would use a sway bar on anything on the front or rear and both when possible especially when stock suspension sytems are regulated.

If you had a solid fron axle, the right rear spring would be hit even harder and the left rear, D/S would extend quicker. This is because the full load from the drive shaft would make the r/r get hit very hard. The front of the drive shaft feels basically nothing. The action of the pinion gear trying to climb the ring gear does it all. As I said, this is exagerated more taller tires, less gear, tighter converters and more NOS

As for your last statement it is incorrect. This will unload the r/r tire even worst. Now if you have an anti roll bar, this will help a ton but the anti roll bar works even harder. Even the anti roll bar will feel more load with a solid front suspension. We don't see it because we don't measure it. Put and load meter between the links and watch what happens with a solid suspension and an independant front suspension. You can do this with different metals and thickness also. Think about it.

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Postby BillyShope » Sun Aug 20, 2006 12:51 pm

awesomebill wrote:If you had a solid fron axle, the right rear spring would be hit even harder....


If the front suspension is truly solid (no deflection) and if the chassis is rigid (isn't twisting like a wet washrag) and if the driveshaft torque is insufficient to lift the right rear tire from the track surface (as is normally the case), how are you going to get any deflection of the rear springs? And, with no deflection of the rear springs, there is no opportunity (with a symmetrical trailing link arrangement) to cancel even a portion of the driveshaft torque's effect on the unloading of the right rear.

awsomebill wrote:Think about it.

awesomebill

Postby awesomebill » Wed Aug 23, 2006 5:49 am

We are not talking about a 4 cyl engine here with no torque. I thought that was a given. When using larger engines, you alway have the body twist from the r/r spring being killed upon the launch. This is what allows the l/f to act like it is rolling over. No power, no action, which would produce a very straight lauch. Like the one I get with my Ford Ranger and its 4 cyl. Now go to a 7 second 3500 lbs street car with a stock suspension and NOS and you got another story. We are not talking about mythical solid front axles, these are real cars with working chassis's with real front ends and are going dead straight with or without a sway bar for the front and rear or an anti-roll bar just for the rear. I do not understand what you are asking or arguing about? Do you have a question concerning the drive shaft and its relationship to body roll or what happens on launch?

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Postby BillyShope » Wed Aug 23, 2006 6:15 am

By using a "mythical" suspension and other constraints, I am using a common engineering analytical tool: Consider the behavior of the system at its limits. When this is done, the actual behavior is known to lie somewhere between.

Unless you can find an error in the analysis, you must agree that a symmetrical car with no suspension at the front and a rigid chassis will exerience no spring deflection at the rear. (This is excluding, of course, that deflection which occurs if the car squats or rises on launch. This spring loading is symmetrical and is not a part of this present discussion. In other words, it has no effect...one way or the other...on the unloading of the right rear. If this is confusing to the analysis, another constraint can be added: The car neither squats nor rises. This additional constraint is not necessary, but it does remove any chance for confusion.) So, if you have no spring deflection at the rear which can be used to cancel driveshaft torque, maximum unloading of the right rear will occur.

Similarly, you must agree that the reversed situation (no suspension at the rear) results in no spring deflection at the front and, consequently, equal rear tire loading during launch.

No, neither of these cars exist, but consideration of their characteristics leads us to an understanding of the effects of relative roll stiffness...front-to-rear...and rear tire loading in a "real" car. We now know that the front roll stiffness is to be minimized and the rear maximized.

Ed-vancedEngines

Postby Ed-vancedEngines » Wed Aug 23, 2006 12:04 pm

For what it is worth;
Both of these mythical cars have existed and have been tried for years.

sprung and suspended straight front axles with solid mounted rear axles have been around for eons. Even those cars did try to lift the right rear tire and did slightly. They also did twist the frames and they did lift the left front tire higher. Those statements sound to be contradictory but that is what was. Those old frames did really twist a lot. You would think that with the engine torque absorbed into the chassis and the left front tire trying to rise that there would have been more tire pressure on the right rear. Just didn't happen. They either loaded evenly or the right came up a little which was established to be fact by the smaller right side contact patch.

Now about the solid monuted front axles; They also existed in early Pro Mod days. there were two early Pro Mods, one a truck and one a Camaro that had a solid front funny car style of front suspension. They both had working 4 links and when either of them launched it looked like any other 4 link car during a launch and the right rear tire tried to climb inside the fender while the front pratically did nothing except to go up and come down and go down the track, but the left front tire is what was always hanging higher.

The Usage of Chris Alstons Percentage of Rise methods are only looking at the basic suspension and the relationships to other stationary parts of the car and use the neutral line as the basis of where the instant center should be placed and if the instant center is in the neutral line it is at 100% no matter how far forward or how rearward the instant center actuallt is. The calculted place to locate the Instant Center for the best Percentage of rise is based entirely on the car and suspension placemets. The actual working engine horsepower or torque as well as any of the drivetrain is not any part of the equation. This is if I can even half way understand the theory. I may be way off base on this.

Achieving your theoretical perfect no rise and no squat scenereo can not exist except with solid mounted rears. Solid mounted rears don't work. Plain and simple. They depend solely on weight distribution, weight transfer and traction coefficient of friction that is a constant and does not change except by conditions or by tires.

The most sophisticated drag racing suspensions will be found on the NHRA Pro Stock cars. The most knowledge and suspension tuning capabilites will also be found there in those who can be in the qualifiers.


Shoot a good close up video of the launch of any of those on the left side and on the right side and then play them back in normal regular speed and watch what is happening in the rear suspensions. Next play them back in a slow motion and you will see some things a little different. Finally play them all in a single frame by frame advance and prepare to see some things that were not visable in regular speed or as your eye could see in real time. In that single frame by frame advance you will discover some of how an actual 4 link rear suspension should work when it is set up correctly. Of course you will realize that they have the capabilites and the knowledge to make the rear or the front suspensions to do anything they desire. They can easily make the cars to launch with both front wheels exactly even in their rise or even to keep the rear of the car to be completely level in the launch. To do so results in a suspension binding that slows down the cars.

Of course I rememebr that Mr Billy has already staTWED THAT A VIDEO OF A DRAG CAR LAUNCHING WILL NOT SHOW MUCH OR BE ANY HELP IN THE SUSPENSION TUNING. (Sorry caps lock comes on by accident).

I do not shoot down the well researched and thought out engineering theories that are using sound engineering principles. BUT those same sound engineering principles did lead an engineer to proclaim that it would be impossible for any type of accellerating vehicle to be able to exceed 150 mph in the standing 1/4 mile, many years ago.

The ultimate and best suspension tuners are the NHRA Pro Stockers and they are fighting to keep a bite all the way down the track on a 17 inch wide tire with arguably 1,400 to 1,440 horses. We are working and fighting and making 1,700 horses to over 2,000 horses to stick to the tracks on 10.50 inches of tire and in the Outlaw clasess with a 10.5 W tire which is actually 11.60 wide. The 100% percentage of rise theory with the no squat and no rise just can not and does not work.

Am open for more discussions though.
Ed


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