Why does the suspension look like i drove over a rock?

RustyRatRod said:

It's not a hollowed out shell, but it's no street car either. Don't take my word as gospel yet. Like I said, I could be wrong. It just seems I remember something funny about how to choose what spring for the rear of these cars.......for racing anyway. For a street car it's easy. @72bluNblu will know. I tagged him. He'll come in here and tell me how wrong I am. LMAO

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Without my DC catalogs here, I can't say for sure, but my memory says the SS springs were sold based on vehicle weight.

If I was home, I could say for sure. I'd have the wife look it up for me, but I could walk the 200 miles home and find it faster. So that is not an option.

yellow rose said:

IDK how to answer that. I doubt 50/50 will help you so you either need to slow the spring down on extension, or on compression.

IOW, the way I understand that shock is you also have a 60/40 and a 70/30 setting. If so, I'd make it so it is on the 70/30 side and try and tune that.

By that I mean you are either going to slow the spring down in extension or compression. That's what you'll have to deal with. But damn, if you slow the spring down in extension, but it's actually less dampening in compression you still might have an issue with the tire unloading.

Can you see the corner you are painted into? One way or the other you are going to compromise spring control. You can work with tire pressure and the other stuff skrewssaid, but still, you are showing up to a gun fight with a pan of noodles.

It would be better if you can slow everything down in both directions, but at this point you are going to have to deal with what you have.

FWIW, when I bought my car it had some junk KYb shocks up front and that 50/50 shock on the rear. So I beat on it awhile, because before I bought the car and it belonged to my cousin so I drove it a bunch.

Anyway, he didn't want to buy a good shock, so that's what he bought and that was on the car when I got it.

I replaced the fronts first with Viking DA shocks. Then the rears. When I pulled the rear shocks off, the one on the right side was toast. It had beat the valving out of it. It had no dampening in either direction.

You get what you pay for.

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Thanks! I have heard some other people that are not happy with these Competition Engineering shock, but also heard about it after i had already bought them.
I haven't even installed them and i don't like the clicking feel that sets them................................

yellow rose said:

Without my DC catalogs here, I can't say for sure, but my memory says the SS springs were sold based on vehicle weight.

If I was home, I could say for sure. I'd have the wife look it up for me, but I could walk the 200 miles home and find it faster. So that is not an option.

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I just cannot remember. To save my big old butt. I know they were LISTED by weight, but I just remember something funny about makin the choice......maybe I'm just gettin senile. Still from the videos, the car looks like it's not working well in the rear.......like it has too much spring.

Years ago, when I lived in Colorado I used to use Competition Engineering shocks with stock springs and a pinion snubber. Car ran 11.0's and Bandimere (bottle fed 360 motor). My car liked the rears with the 50/50 setting and the fronts with 90/10. If it is what you have right now, I would just give it a go...it may work just fine for you.

I eventually switched to a full Caltrac setup with mono leafs. With the old suspension my car would pull the driver side tire about a foot off the ground with the passenger side only inches off the ground...it was ugly. Caltrac setup fixed it...nice and level now, faster and more consistent....they also crushed my axel tubes on my old 8 3/4 the first day using them, but that's another story...

Cudafever said:

Ok so first, we got rained on 3 different times and all thow we dragged the track after each rain shower, the track was just plain cold.
The butt odometer said the tire hopped and slipped off the line. but my gopro shows no tire slip at all. But the suspension bumps like it just drove over a rock.
This is a 2 minute video that shows the launch once at regular speed. Then super so mo, the 2nt time.
It make it super blurry and the sun reflecting off the inside of the rim dont help the quality any better. Take a look and tell me you thing is happening here.
Thanks

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RustyRatRod said:

It's not a hollowed out shell, but it's no street car either. Don't take my word as gospel yet. Like I said, I could be wrong. It just seems I remember something funny about how to choose what spring for the rear of these cars.......for racing anyway. For a street car it's easy. @72bluNblu will know. I tagged him. He'll come in here and tell me how wrong I am. LMAO

Click to expand...

So after watching the video a whole bunch of times, I'm still not entirely sure what's going on in that first tire revolution. It looks to me like there was a tiny bit of tire slip. Now, whether the tires slipped because of the tires, or the tires slipped because of a spring reaction is impossible to tell from that video. In the first revolution the springs are unloading, the video clearly shows the suspension loading as you prepare to launch (as it should). That little hiccup as you launch and the springs release could be darn near anything. A small bind in the release of the springs would do that, and based on what's in the video it's really small. Could be a tight spot in the shackles, a bind in the leafs themselves as the slide a little bit over each other, a shock issue, you name it. If you are running shackles I would check to make sure they're not overtightened and that they're properly lubed. Same for the U-bolts and everything else, if something is overtightened it can cause binding. Make sure everything is torqued to the proper spec.

The SS springs are sold by vehicle weight. The only exception is the 002/003 springs, which are the original pro-stock springs and didn't have their part #'s changed in 1974 when Mopar reclassified all the SS springs and gave them new part #'s. But they also have an associated vehicle weight. You can see the currently available springs at Summit Racing Springs - mopar-performance-springs

This page is out of a "Mopar rear suspension racing manual", released January 1980 as PN P4007927, Bulletin #30. It covers a bunch of different suspensions, but has a lot of info on the SS spring set ups. Unfortunately even just the leaf spring section is too big to attach, even as a zip file. It lists most of the available SS springs now, looks like a couple may have been added since then.



Like Rob said I seem to recall there being more to it than just picking your vehicle weight and buying the corresponding spring. I think there were some corrections for that and I was hoping they were in the bulletin but I didn't see them right off and I'm not gonna go back through all 68 pages right now. I do know that when I ran 3400# SS springs on my Challenger I found them to be ridiculously stiff, but I was running it on the street. Similarly I know that a lot of the guys that run the 002/003 springs have cars that probably weigh a bit more than 3,000 lbs.

But I will readily admit I'm not a drag racing guy. Drag racing spring rates tend to be a lot higher than what you'd want to run on the street. For street and handling performance usually an A-body is good with 120-130 lb/in leafs. But for drag racing the 002/003 springs are usually the go to, and they're 160 lb/in. Obviously it all can change with car weight and set up, those are just general numbers.

72bluNblu said:

So after watching the video a whole bunch of times, I'm still not entirely sure what's going on in that first tire revolution. It looks to me like there was a tiny bit of tire slip. Now, whether the tires slipped because of the tires, or the tires slipped because of a spring reaction is impossible to tell from that video. In the first revolution the springs are unloading, the video clearly shows the suspension loading as you prepare to launch (as it should). That little hiccup as you launch and the springs release could be darn near anything. A small bind in the release of the springs would do that, and based on what's in the video it's really small. Could be a tight spot in the shackles, a bind in the leafs themselves as the slide a little bit over each other, a shock issue, you name it. If you are running shackles I would check to make sure they're not overtightened and that they're properly lubed. Same for the U-bolts and everything else, if something is overtightened it can cause binding. Make sure everything is torqued to the proper spec.

The SS springs are sold by vehicle weight. The only exception is the 002/003 springs, which are the original pro-stock springs and didn't have their part #'s changed in 1974 when Mopar reclassified all the SS springs and gave them new part #'s. But they also have an associated vehicle weight. You can see the currently available springs at Summit Racing Springs - mopar-performance-springs

This page is out of a "Mopar rear suspension racing manual", released January 1980 as PN P4007927, Bulletin #30. It covers a bunch of different suspensions, but has a lot of info on the SS spring set ups. Unfortunately even just the leaf spring section is too big to attach, even as a zip file. It lists most of the available SS springs now, looks like a couple may have been added since then.

View attachment 1715341395

Like Rob said I seem to recall there being more to it than just picking your vehicle weight and buying the corresponding spring. I think there were some corrections for that and I was hoping they were in the bulletin but I didn't see them right off and I'm not gonna go back through all 68 pages right now. I do know that when I ran 3400# SS springs on my Challenger I found them to be ridiculously stiff, but I was running it on the street. Similarly I know that a lot of the guys that run the 002/003 springs have cars that probably weigh a bit more than 3,000 lbs.

But I will readily admit I'm not a drag racing guy. Drag racing spring rates tend to be a lot higher than what you'd want to run on the street. For street and handling performance usually an A-body is good with 120-130 lb/in leafs. But for drag racing the 002/003 springs are usually the go to, and they're 160 lb/in. Obviously it all can change with car weight and set up, those are just general numbers.

Click to expand...

Now that you mention it...when I bought my SS springs it wasn't just car weight. It also mattered how fast you thought you were, and since I ran a stick, it took a different spring than what the weight called for.

I still hated them. They were a ***** with the stick and were really bad lifting on the big end.

You don't need high $$$ parts for a 1.70 60. I run CE 90/10 front 50/50 rear 20 psi MT Street SS drag radial. The difference in rear tire grip is most likely the sure grip clutch slipping more on the right rear. RT rear is loaded more on launch with SS spring. I would put the CE shocks on, air up the tires, fix the sure grip or put a spool in if it's a track car.

I think I see something unusual
In the slo-mo, I see the rear of the car rise and hang there for a long time.
Then it begins to rise more and the pinion rotates waaay up,like the power was twisting the front section of the spring
Then the pinion does an up and down dance, like the u-joint is bound up, but I think it's just the springs winding up and letting go..
Don't know if it means anything.......

At 42 seconds, you can see the lower shock mounts twisting downwards
At 56 seconds the the shock anchors are twisted waaaaay down. and the dance begins. watch the shock pins. The dance doesn't end until the shift. If you watch the springs and do some deductive reasoning, I think those front spring sections are alive! rippling back and forth.
Don't know if it means anything.......

72bluNblu said:

So after watching the video a whole bunch of times, I'm still not entirely sure what's going on in that first tire revolution. It looks to me like there was a tiny bit of tire slip. Now, whether the tires slipped because of the tires, or the tires slipped because of a spring reaction is impossible to tell from that video. In the first revolution the springs are unloading, the video clearly shows the suspension loading as you prepare to launch (as it should). That little hiccup as you launch and the springs release could be darn near anything. A small bind in the release of the springs would do that, and based on what's in the video it's really small. Could be a tight spot in the shackles, a bind in the leafs themselves as the slide a little bit over each other, a shock issue, you name it. If you are running shackles I would check to make sure they're not overtightened and that they're properly lubed. Same for the U-bolts and everything else, if something is overtightened it can cause binding. Make sure everything is torqued to the proper spec.

The SS springs are sold by vehicle weight. The only exception is the 002/003 springs, which are the original pro-stock springs and didn't have their part #'s changed in 1974 when Mopar reclassified all the SS springs and gave them new part #'s. But they also have an associated vehicle weight. You can see the currently available springs at Summit Racing Springs - mopar-performance-springs

This page is out of a "Mopar rear suspension racing manual", released January 1980 as PN P4007927, Bulletin #30. It covers a bunch of different suspensions, but has a lot of info on the SS spring set ups. Unfortunately even just the leaf spring section is too big to attach, even as a zip file. It lists most of the available SS springs now, looks like a couple may have been added since then.

View attachment 1715341395



Like Rob said I seem to recall there being more to it than just picking your vehicle weight and buying the corresponding spring. I think there were some corrections for that and I was hoping they were in the bulletin but I didn't see them right off and I'm not gonna go back through all 68 pages right now. I do know that when I ran 3400# SS springs on my Challenger I found them to be ridiculously stiff, but I was running it on the street. Similarly I know that a lot of the guys that run the 002/003 springs have cars that probably weigh a bit more than 3,000 lbs.

But I will readily admit I'm not a drag racing guy. Drag racing spring rates tend to be a lot higher than what you'd want to run on the street. For street and handling performance usually an A-body is good with 120-130 lb/in leafs. But for drag racing the 002/003 springs are usually the go to, and they're 160 lb/in. Obviously it all can change with car weight and set up, those are just general numbers.

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Great idea on the shackles, you may have something there. on the lube as well as tightening!
I did set the car on the ground and bounce it, with the shocks removed before i tightened everything up.
Them rear shackles have nylock on there for a reason and i may have got a little bit rambuncis on them.
I will try and find a spec for torque and disassemble and lube them up.......i didn't do that when i installed them......didn't even think about it.

mderoy340 said:

You don't need high $$$ parts for a 1.70 60. I run CE 90/10 front 50/50 rear 20 psi MT Street SS drag radial. The difference in rear tire grip is most likely the sure grip clutch slipping more on the right rear. RT rear is loaded more on launch with SS spring. I would put the CE shocks on, air up the tires, fix the sure grip or put a spool in if it's a track car.

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The clutches are new in the sure grip. maybe 20 pass on them. I don't want a spool.........but in the end i may have to go that route.
Thanks for the thoughts on shock setting.

AJ/FormS said:

I think I see something unusual
In the slo-mo, I see the rear of the car rise and hang there for a long time.
Then it begins to rise more and the pinion rotates waaay up,like the power was twisting the front section of the spring
Then the pinion does an up and down dance, like the u-joint is bound up, but I think it's just the springs winding up and letting go..
Don't know if it means anything.......

At 42 seconds, you can see the lower shock mounts twisting downwards
At 56 seconds the the shock anchors are twisted waaaaay down. and the dance begins. watch the shock pins. The dance doesn't end until the shift. If you watch the springs and do some deductive reasoning, I think those front spring sections are alive! rippling back and forth.
Don't know if it means anything.......

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I'm going to make another slow mo that's not as slow and see if it becomes less blurry............ maybe a couple different speeds.
Thanks everyone for your help so far.

Here you go.
There is 3 of them, the first one is at half speed and the hole run and some shut down footage.
the next 2 are only the launch and are 1/4 speed (.25) and the last one is at .10
My super slo mo was at .04 and it's just to slow.
Injoy and let me know what you see think about it!!!!

How many clamps on the front segments? I don't see any that I can confirm.

one on each spring factory spring clamp
there just stamped steel clamps

Ok so i have play my latest video over, and over, and what i noties is a.... vibration of the spring pack on the left one. Just behind the axle. This could just be the blur of the video but it happens at the hop...............
I my have tighten them shackles to much and it's causing a bind just like 762bluNblu suggested.

What are you guys seeing?

Cudafever said:

one on each spring factory spring clamp
there just stamped steel clamps

View attachment 1715341634

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Just ONE per side? There should be as many clamps as leafs stacked together. I have the 6 leaf +2" under mine and it has three times the clamps yours does. I remember sometimes when I ordered SS springs, the clamps were included but not installed. Also sometimes they were left out altogether, but they need to be there. The rule of thumb was clamp the front segment and unclamp the rear segment. I'd sure add some and see if it makes a difference. Very low cost and the labor is free. What have you got to lose at this point?

I think i have found.....Ah....... smoking gun.
So to fit the bigger slicks, i had to move my leaf spring inward causing me to have to us off set shackles.
The offset shackles clear just fine on the right side however Not so much on the other side. My bumpers have them little bumper guards on them. they bolt to the sub frame and are both trying to share the same space.

RustyRatRod said:

Just ONE per side? There should be as many clamps as leafs stacked together. I have the 6 leaf +2" under mine and it has three times the clamps yours does. I remember sometimes when I ordered SS springs, the clamps were included but not installed. Also sometimes they were left out altogether, but they need to be there. The rule of thumb was clamp the front segment and unclamp the rear segment. I'd sure add some and see if it makes a difference. Very low cost and the labor is free. What have you got to lose at this point?

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just when out and looked. one clamp on the front and one on the back of each leaf spring.
I had these heavy duty ones on my old SS Springs. so the cost is "0" just didn't think i need them on a new set.

Well......here's how "I" always did it.....your methods may vary. I always tried it "wide open" first. In other words NO clamps on the rear segments and ALL on the front and tune from there. Removing them from the rear will make it hit harder. Clamping them on the front will make it hit harder. Somethin's up with yours. It leaves really soft. No offense. Did you tighten all the suspension bolts with the weight on the tires?

Cudafever said:

I think i have found.....Ah....... smoking gun.
So to fit the bigger slicks, i had to move my leaf spring inward causing me to have to us off set shackles.
The offset shackles clear just fine on the right side however Not so much on the other side. My bumpers have them little bumper guards on them. they bolt to the sub frame and are both trying to share the same space.


View attachment 1715341640 View attachment 1715341641

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That is interesting!

So why do you think it's soft? seems like everyone else is saying it's hitting too hard and i need better shock to control it.
Paint me a picture of my suspension hitting harder in your eyes. Please.

all bolts were left loose until it landed on my garage floor.

RustyRatRod said:

That is interesting!

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Its a simple fix. loosen bolt that hold that bumper guard and shift it over, re tighten it. I will do that while i'm greasing up the bushings.

Cudafever said:

So why do you think it's soft? seems like everyone else is saying it's hitting too hard and i need better shock to control it.
Paint me a picture of my suspension hitting harder in your eyes. Please.

all bolts were left loose until it landed on my garage floor.

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Looking at the car when it launches and the suspension it just seems to me that it's not hittin hard at all. The couple times the video shows the car leaving, there's not a lot of room between the tires and the wheelwell. Looks like there's not a lot of body rise.

"butt odometer" says i fix the problem with the "driving over a rock situations."

Made clearance for the off set rear shackles, lubed up bushings, installed rear "three way" shock set at 50/50.
Got my first 1.6x 60' time,(1.689) my first 88 mph time. Also was able to lower my air pressure because i finally put my rims drill for screws( The rim slipped on the tire, about a 1/2" last race.)
Air density was exceptionally good for our track at 6800- 7900 feet all day.(6600 foot elevation track) Improved my et from a 7.78 to a 7.73.
I still have traction issues as the grip go's away in the afternoon. Seem to spin more or longer then before with the old shocks. But it was a vary cold day also. I'm not going to change the rear shock setting until i get my 91/10 shock installed up front.

I ran out of time and didn't get my 90/10 shock installed up front. (Long story.)

This is a vary short video. Forgot to charge my GoPro and the battery when dead. The traction issue happen later in the day and GoPro's battery was dead.

Looks like you got more rise, and less S in the front half of the springs, Nice.
What about the crunch you were talking about in the earlier post?
But that pinion is really wrapping up, can't wait to see it with the 90/10s

crunch? what post #