Rebound on left front shock

[mab475]

I was a crew chief on a 09 Swartz with a floating X. One of the best cars I ever worked on.

[7uptruckracer]

I forget if his is a GRT or Swartz the Swartz is very popular at Winchester, Pettyjohn is crushing them up there in one.

[hipower17]

what size track would u tie the front down?

[3wheelinphotos]

An this post is exactly why people in industry sit an laugh at this site..... PENSKE SHOCKS get on here states what they have found in test an what you all do..... Pretty much say nah this is the way it is! WoW carry on guys!

[7uptruckracer]

They didn't state anything about the physics we are talking about, their competition director just stated what they found that helped some only some of their clients.... They had to start out somewhere too. Debate back and forth and working through problems and wording is how things get done and people learn and pick and choose what they want to apply. If you're in the industry please for our benefit state who you're with so we don't have to support someone so condescending. You can't state "facts" that fly in the face of the Laws of Physics. If your going to try to talk condescending we might take you more seriously if you at least use correct grammar and spelling.

[fastford]

heres my opinion or whats going on from a physics standpoint,does weight move diagonally??? the answer is no,now I can understand why some people would think so but its impossible,i could break it down but it would be 9 pages long to explain about a late model going 100mph and then slowing to 60mph,
it takes two movements to get the weight to the rr,the car has to fall to the rear and with the side load to the right,now in a late model this happens at a very high rate of movement,but again I can see how some would think it moves diagonally,but in a physics world its two or more movements
this is without getting in great detail,just trying to help some understand whats going on
I could explain it but you have corner entry,mid corner,exit, straightaway,but then would have to wright a 20 page article,
mark bush and some others have classes on this,
just trying to explain from a phyics standpoint and not trying to ruffle any feathers

were not talking about weight being physically moved, that would be a static placement, but in the dynamic world of a late model, going around a race track, I would bet the bank , if you put weight sensors on the car, similar to what indy cars do, you would see a weight transfer difference on the right rear with the left front tied as opposed to not tied and light rebound, with that being said , ill stand by my theory that weight will move diagonally , not physically, but dynamically from left front to right rear

[7uptruckracer]

You might very well see a NET change that shows on a diagonal migration in dynamic weight. You gain more LF to RR but the two physical forces that acted on the car that did it aren't a diagonal force, that's all me and the others are saying, its just two forces that act at the same time to give you that reading. Look it up is all i can say, all you will ever see referenced is Lateral and Longitudinal you're only doing two actions Steering and Braking/Accel. You might have a theory but Physics are laws. If you're saying you will see a digital migration/rake on paper or in a computer with data acquisition if you compare your opposing corners absolutely correct the force that got them there though not possible. Regardless interesting conversation and I'm sure we all run up front where ever we race being we can have this back and forth too early banter.

[fastford]

dang 7up you must live on here, you guys are getting to technical for my old hjllbjlly azz, but please refer me to the physics book that will explain to me how diagonal dynamic weight load does not exist, which is basically what the original poster was wanting to know in asking for the effects of tying the lft front, any way ive enjoyed this discussion more than any on here in a while but were finally thawing out so its back to the grind, yall have a good day

[7uptruckracer]

I'm avoiding working at work its to cold and the coffee is all gone.

[fastford]

hey 7up, check you pm

[mab475]

From the photo you posted it looks to be a Swartz

[7uptruckracer]

I asked it is. It probably says it on the car I didn't look and I don't get up to that track to much to be to familiar with what he's running but it's attitude is what turned me on to the idea of that there might be something to seal the nose flat and keeping the LF tied to help corner entry to middle and get away from excessive hike and steer. It's a 2011 Swart their new car is exploding all over down here.

[4bangerhotrod]

I think the way the weight transfers depends a lot on the position on the car an the attitude of the car while it's transferring

[Matt49]

Good point 4banger. When weight transfers "laterally" due to steering input while on the gas when the car is already yawed, that's where I feel the most transfer from LF to RR. At that point, the car is not traveling in the same direction it is pointing to LF, RF, LR, RR are not "normal" like a squared car going down the track. I'm probably doing a bad job of explaining but maybe you guys will understand what I'm talking about.
When talking about what the car is doing on the track these days, my dad and I talk a lot less about loose and tight, and a lot more about roll, pitch, and yaw.
The cars are just so much more dynamic than they used to be.

[7uptruckracer]

I wish my dad talked to me about those things all I get is you have this much money in these racecars back in my day we towed to car to the track took the motor out the truck put it in the car and hope you didn't blow it so you could drive yourself home later lol....

[4bangerhotrod]

We have to remember when your talking about theory these cars are never really going in a straight line, most tracks the car will never be straight the car is always turning. So you have to be able to visualize in your mind where the weight is going to go how much is going to each place an what it's going to do when it gets there. it's little stuff like this that makes a big difference an separates top teams from for the rest.

[adamsraceshocks]

http://www.teamgrt.com/TUNING_THE_CAR_WITH_SPRINGS.pdf
According to "experts" I have herd explain this the lf to rr you are feeling is a combination effect, so in a way you both are right... in order to get from the lf to the rr it has to also come from either the rf or the lr. The heavy spring takes the load. From what I have seen shocks used to first control the spring, second to control timing of transfer and third to control attitudes and angles. Everything is a compromise the more you use a shock to control angles and attitudes of the car the less you can use it to control the spring. That being said shocks are the easiest place to "have your cake and eat it too" when it comes to adjusting due to the fact you can have the same shock do differnt things depending on if it is going in or out, and can also change based on the speed it moves in or out.

[grt74]

were not talking about weight being physically moved, that would be a static placement, but in the dynamic world of a late model, going around a race track, I would bet the bank , if you put weight sensors on the car, similar to what indy cars do, you would see a weight transfer difference on the right rear with the left front tied as opposed to not tied and light rebound, with that being said , ill stand by my theory that weight will move diagonally , not physically, but dynamically from left front to right rear

ok just to give an example,you entered the corner and just got to the middle and started to pick up the throttle what happens???
from the middle of the corner with the rf loaded you hit the throttle where did the weight go and where did it come from???
now for the most part the right is loaded already(weight from the left has moved to the right from corner entry to the middle)
next you hit the throttle hard,what happens???the weight from the front moves to the rear(and by that I mean both rear tires get weight but the rr does get a higher %)
and some times the weight moves so fast that it picks the lf up and carries it
theres just a small example of whats going on,and this is in a dynamic world
set up,set up,set up is all I can say
who would have thought all that homework would be needed one day???

[7uptruckracer]

If geometry, trig and calc in high school and college used racecar word problems I would have paid more attention.

[grt74]

remember you have lr drop,bars angles and about 100 other things that have effects also