Chassis Tuning

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Archeryguy02 said:
I am running SS springs which I have read work on a totally different philosophy from what I have read.
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The first and most important fact to understand and keep in you head Is..............."FOR EVERY ACTION, THERE IS A EQUAL AND OPPOSITE.
examples: crank turns CC(counterclockwise) directions. What ever torque is generated from that motion has a Equal/Opposite torque on the chassis causing the left front frame rail to raise.

Drive shaft turns CC and the hole rear end housing wants to rotate in the same direction. Trying to pull the Right rear axle/tire off the ground and shove the left side into the pavement.(Aka right side SS Spring is stiffer trying to control this force) This is also why you put the battery on the right side, when you put the battery in the trunk.

The t-bars can be adj to get you more travel, causing more weight transfer.
Also adding more turns to the left front T-bar will raise the left front, But will also add more weight (bite) in the Right rear tire.
Equal/opposite reactions

If you want to see an example of this go here and read post 43
How much will adding 16 lb to my car affect ET/mph(rotating weight)

When you install inferior tires on the back of your car. That you don't have a chance in H*ll of getting to hook up. You can see just how far your suspension is f up and adjustments are more obvious.
 
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polyurathan bushings in front will help front end movement a lot, let it rise way easier and faster. transfers weight better, sounds like converter is bit tight, use lower launch rpm, make convertor hit harder. just food for thought.
 
Cudafever said:
The t-bars can be adj to get you more travel, causing more weight transfer.
Also adding more turns to the left front T-bar will raise the left front, But will also add more weight (bite) in the Right rear tire.
Equal/opposite reactions
Click to expand...

Asking for clarification because this paragraph seems contradictory.
To get more travel for more weight transfer, you would need to take turns out to lower the left-front torsion bar in order to get more transfer and "throw" more weight on the right-rear, if the car is pulling right. Lowerered left-front gives more travel (running start) and looser shocks make the travel easier. At least that worked for me with adjustable shocks up front set towards the loose side. However, it seems like stiffer front shocks wouldn't be as effective because it would be more difficult to raise/transfer/throw the weight.

My rear shock philosophy is the harder it leaves, the stiffer the shocks should be. Mopar had "auto" and "stick" rear shocks long ago. But I found out that converter and engine technology had surpassed their original recommendations since their 'stick" rear shocks weren't enough my particular auto/footbrake combo and I went to Rancho 9-way rear shocks.

OP - It's a complicated formula with a lot of factors to consider. Like an "orchestra", it ALL has to work together to get the "music" you want.
 
Locomotion said:
Asking for clarification because this paragraph seems contradictory.
To get more travel for more weight transfer, you would need to take turns out to lower the left-front torsion bar in order to get more transfer and "throw" more weight on the right-rear, if the car is pulling right. Lowerered left-front gives more travel (running start) and looser shocks make the travel easier. At least that worked for me with adjustable shocks up front set towards the loose side. However, it seems like stiffer front shocks wouldn't be as effective because it would be more difficult to raise/transfer/throw the weight.

My rear shock philosophy is the harder it leaves, the stiffer the shocks should be. Mopar had "auto" and "stick" rear shocks long ago. But I found out that converter and engine technology had surpassed their original recommendations since their 'stick" rear shocks weren't enough my particular auto/footbrake combo and I went to Rancho 9-way rear shocks.

OP - It's a complicated formula with a lot of factors to consider. Like an "orchestra", it ALL has to work together to get the "music" you want.
Click to expand...
Will clarify in a bit when I get home.
 
Locomotion said:
Asking for clarification because this paragraph seems contradictory.
To get more travel for more weight transfer, you would need to take turns out to lower the left-front torsion bar in order to get more transfer and "throw" more weight on the right-rear, if the car is pulling right. Lowerered left-front gives more travel (running start) and looser shocks make the travel easier. At least that worked for me with adjustable shocks up front set towards the loose side. However, it seems like stiffer front shocks wouldn't be as effective because it would be more difficult to raise/transfer/throw the weight.

My rear shock philosophy is the harder it leaves, the stiffer the shocks should be. Mopar had "auto" and "stick" rear shocks long ago. But I found out that converter and engine technology had surpassed their original recommendations since their 'stick" rear shocks weren't enough my particular auto/footbrake combo and I went to Rancho 9-way rear shocks.

OP - It's a complicated formula with a lot of factors to consider. Like an "orchestra", it ALL has to work together to get the "music" you want.
Click to expand...

I don't disagree with any of that.
My 2nd Sentence makes sence only in my mind.:wtf::D

K so if you had scales on all for tires, and you tightened the driver side front(LF) t- bar you would add more weight to that wheel as well as loosing a small amount to the driver side rear wheel(LR). But would add more weight to the right rear tire(RR).

SS Spring have a Stink Bug look and also have what i call the Gangster Lean. AKA the RR sets Higher then the LR does, Right?

So when i replaced my SS Spring with a new set. And rebuilt my front end with less friction front end parts. And with vary little data on tuning this type of suspension. i decided to make the LF T-bar hold most of the weight of the front end. this caused the gangster lean to go away.(causing it to load the RR tire and lift, take weight off of LR

With a good set of slick, and me not making enough Power to pull the front end up. all seamed OK. When i put my "dot tires on that were more like pizza cuter tires, compared to my slicks, and they would not hook.
More importantly it would kick sideways every time i tried to do a long burn out............also kicked out when i launched and spun all the way out.

I had no clue if turning the LF T-bar loose was going to help or make it worse. as luck would have it it made it better and after 3 full turn of the T-Bolt, out or loose. it launched straight, even though i was roasting the tires through 1st and 2nt gear.

So when i said: Adding more turns to the left front T-bar will raise the left front, But will also add more weight (bite) in the Right rear tire. It was the excessive tension on the LF T- bar that caused my car to go right(*** end went right) and is why i said that.

All thoughts welcome. Still learning on this stuff.
 
Cudafever said:
There is nothing wrong with this book or any other chassis book out there..................But!
I have yet to find one that has more, them one Paragraph, on SS Spring chassis tuning.

Lower front end to allow at least 5" of UP Travel from resting height. (I know it sounds backwards, but it allows you to throw the weight from the front end to the rear faster) Remember this will mess up your front end alignment. (reset your toe after adj and you will be fine). consider an alignment after your satisfied on the ride height.

I don't think you can get a descent and efficient Stall Converter with a "Lock Up" 904. (3500-4000 stall)

Is your stall low because you don't have enough timing in it, or full advance of the timing coming in to slow??

Low first gear help a lot when you have a tall gear.

I had vary little traction issues until i went from a 2800 stall to a 4200.

408/727/4.56 gears 28/10.0/15 M/T Slick.
Yes, SS Spring, Torsion bar suspension on a 3800 pound car.

Now let me ask you a question.
When you stall it up to 2000 rpm.......is it loading the rear end? Do you feel the rear end start to rise?? If so try leaving at a lower rpm (If its slipping of the line) and see if you get a better 60" time.
Click to expand...

I also paid attention to how much the 2000 launch was loading the chassis and it was very slight.

I made it to the track on friday and filmed a few launches, there was no tire spin and the car appears to transferring weight as it should with the new shocks and lowered front end.

I have launched the car a few times at lower RPM and it certainly doesnt help the 60'

Thank you for the info.
 
Every car is different. try a full throttle launch(if the brakes will hold it).

lets see them videos:thumbsup:
 
Iphone, slow-mo video of the launch. Moving the front ride height does something that I don’t think has been mentioned. You want the front end to rise as much as possible in a controlled way. Too fast and it tops out and it with bounce the rear tire. The best way to control it is with the shock. Lowering the front ride height makes it travel more, which takes more time, which can slow how quickly it tops out. Front height changes come with issues. Lowering the front ride height changes the % of rise. Which is the how much the rear of the car goes up and the axle goes down at launch. Which seems to be a good thing, but too much of a good thing and the tire is crushed or bounces. A bodies because of the short front spring section naturally have a high % of rise. Lowering the nose gives it more. This is VERY crude, but take a picture of the car from the side. Print it out and draw a line from the contact patch of the rear tire through the front spring eye.extending out forward through the car. This is the instant center line. Now draw a line parallel with the ground at about the height the cam is off the ground. This is a guess on where the neutral line would be. Now draw a line through about where the shifter ball would be on a stick car vertically, the center of gravity line. The intersection of the neutral and center of gravity line is the true center of gravity point. Where the instant center line and the neutral lines intersect determines the % of rise. Farther forward less rise, hits the tire softer. Farther rearward hits the tire harder. I just put /6 bars in my car, my car tops the front out perfectly with the 340 bars I had in it. However, because 340 bars have less stored energy I was on full loose on my front shocks. It was working so why change? Watching videos of my launch, the car transfers weight, the axle doesnt move in or out of the car. You can see the tire bulge at the bottom as it gets more weight and here is what I want to tune. After the tire shows the bulge only then does the car start to rotate and lift the nose. I’m trying to make it more of a seamless process instead of two distinct actions. /6 bars will have more stored energy. The nose should start to come up quicker which I can slow down with the shock if I have to and the car rotate a hair sooner.

E2B8BE3A-215B-4E97-BDDD-DE8D7EFA3D4C.jpeg
 
If your converter stalls too low. Leave at idle. Give the motor as much of a running start at the converter as you can.
 
Cudafever said:
Every car is different. try a full throttle launch(if the brakes will hold it).

lets see them videos:thumbsup:
Click to expand...
LMAO yah I have pushed through to a deep stage unintentionally getting too aggressive with getting up on the converter.
 
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furrystump said:
If your converter stalls too low. Leave at idle. Give the motor as much of a running start at the converter as you can.
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Unfortunately my tranny is slipping 2nd gear so its coming out, and there is little chance of that converter going back in as is.
 
2nt gear slip can be as simple of a fix as a 2nt gear band adj...............or as bad as a transmission overhaul.
Pull the pan first and see what you find.
chunks carry on. no metal and the band is loose........you might get a few more miles out of it before you pull it.
 
Also you say you have a TF-2 shift kit.
If you don't have the Kick down adj just right, AND your manually shift it through the gears, you can burn up the 2nt gear band.(Or rev. band.)
When i went to a RMVB all of them problem when a way. Because there is no timing between rev band and 2nt band. Also make for a vary strong 1-2 shift. Mine is a 727, don't know if it completely apply to a 904 let alone a 904 Lock up TQ unit.
Just some food for thought......................................
 
Cudafever said:
Also you say you have a TF-2 shift kit.
If you don't have the Kick down adj just right, AND your manually shift it through the gears, you can burn up the 2nt gear band.(Or rev. band.)
When i went to a RMVB all of them problem when a way. Because there is no timing between rev band and 2nt band. Also make for a vary strong 1-2 shift. Mine is a 727, don't know if it completely apply to a 904 let alone a 904 Lock up TQ unit.
Just some food for thought......................................
Click to expand...
Yah, hindsight being 20-20 this tranny was probably weak before I put the shift kit in and was shifted manually for quite a while prior to adding the shift kit. It did have a Lokar kickdown on it the whole time, regardless a manual valve body is the preferred direction for this application.
 
Cudafever said:
2nt gear slip can be as simple of a fix as a 2nt gear band adj...............or as bad as a transmission overhaul.
Pull the pan first and see what you find.
chunks carry on. no metal and the band is loose........you might get a few more miles out of it before you pull it.
Click to expand...
I looked at that as well but at this point I need to pull the tranny anyway to change the converter and I dont want to put a bandaid on this issue and worry about it the rest of the year.
 
Cudafever said:
The first and most important fact to understand and keep in you head Is..............."FOR EVERY ACTION, THERE IS A EQUAL AND OPPOSITE.
examples: crank turns CC(counterclockwise) directions. What ever torque is generated from that motion has a Equal/Opposite torque on the chassis causing the left front frame rail to raise.

Drive shaft turns CC and the hole rear end housing wants to rotate in the same direction. Trying to pull the Right rear axle/tire off the ground and shove the left side into the pavement.(Aka right side SS Spring is stiffer trying to control this force) This is also why you put the battery on the right side, when you put the battery in the trunk.

The t-bars can be adj to get you more travel, causing more weight transfer.
Also adding more turns to the left front T-bar will raise the left front, But will also add more weight (bite) in the Right rear tire.
Equal/opposite reactions

If you want to see an example of this go here and read post 43
How much will adding 16 lb to my car affect ET/mph(rotating weight)

When you install inferior tires on the back of your car. That you don't have a chance in H*ll of getting to hook up. You can see just how far your suspension is f up and adjustments are more obvious.
Click to expand...
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Finally , some one got it all right . never understood putting the battery on the drivers side in the trunk=counterproductive !
 
Update. I rebuilt the tranny and upgraded most things to race trim including a full reverse manual valve body and a 4200 converter. I never had any traction issues, the car launched well.

First full pass was a 11.77 @ 114.35
 
Archeryguy02 said:
Update. I rebuilt the tranny and upgraded most things to race trim including a full reverse manual valve body and a 4200 converter. I never had any traction issues, the car launched well.

First full pass was a 11.77 @ 114.35
Click to expand...
Nice! Picked up half a second....looks like it is working as it should now. :thumbsup:
 
Amazin, aint it? Add not one horsepower, pick up a half second with a converter and driveline work.
Happens quite often with a good converter swap.
 
Cudafever said:
The first and most important fact to understand and keep in you head Is..............."FOR EVERY ACTION, THERE IS A EQUAL AND OPPOSITE.
examples: crank turns CC(counterclockwise) directions. What ever torque is generated from that motion has a Equal/Opposite torque on the chassis causing the left front frame rail to raise.

Drive shaft turns CC and the hole rear end housing wants to rotate in the same direction. Trying to pull the Right rear axle/tire off the ground and shove the left side into the pavement.(Aka right side SS Spring is stiffer trying to control this force) This is also why you put the battery on the right side, when you put the battery in the trunk.

The t-bars can be adj to get you more travel, causing more weight transfer.
Also adding more turns to the left front T-bar will raise the left front, But will also add more weight (bite) in the Right rear tire.
Equal/opposite reactions

If you want to see an example of this go here and read post 43
How much will adding 16 lb to my car affect ET/mph(rotating weight)

When you install inferior tires on the back of your car. That you don't have a chance in H*ll of getting to hook up. You can see just how far your suspension is f up and adjustments are more obvious.
Click to expand...
^^^^^^^^^^^^^^^^^^^^^^^^
correcto mundo .--------------- never understood why anybody would put the battery on the wrong side , if running only one .
 
furrystump said:
If your converter stalls too low. Leave at idle. Give the motor as much of a running start at the converter as you can.
Click to expand...

agreed, was gonna say the same thing. Might hit that dinky convertor harder.
Stock stroke small block Mopars like convertor, all of them.
I would be looking at a tight 8 inch somewhere around 4500 flash.
Car needs to be running more than 5500 at the stripe too….if you are looking to make it ET better
I would also crank the T bars UP…. Help get the car on the tire and transfer weight easier, especially without a convertor.
I ran a heavy(3350 pound) 9 sec smallblock for years on 002/003 leafs, they work.
Video would help
 
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