Street/Mostly Strip Front Suspension

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SpeedThrills

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I've cloned my 74 Dart Sport into a 70-71 Duster. As the title implies, it will be street driven, but not much. It'll get used at the track. It should weigh about 3000 lbs. w/ driver. It has a small block, automatic, glass hood, fenders, and bumpers. It has 6 cyl. torsion bars. (About .854" w/ paint.) To start out, it has 6 cyl. leafs that have poly bushings and are front half-clamped, and new stock shocks. Down the road, it'll get Calvert mono springs and Caltracs, with a corresponding shock. It'll probably run mid-high 11's.

I don't want to use aftermarket control arms strut rods or K- member. My goal is to have freedom of movement. I have more time than money. :)

The steering components are tight. It needs lower ball joints, and I'm replacing the uppers while I'm at it. Who makes good ball joints? On RockAuto, I see prices from $13 to about $40.

I'm guessing that poly bushings are the way to go. I'm all but sure I want them on the strut rods and lower control arms , as they handle a lot of the stress. But will they allow for a "loose" suspension?

The upper bushings. Also poly?

My 1980 :eek: Direct Connection book recommends stock front shocks, of varying strength, depending on the e.t. Sounds old school. Without going straight to a high dollar shock (I'll get better shocks when I get the Calvert stuff), what's a good place to start?
 
Save your money onto Calvert shocks. You need something that is double adjustable. For the cost difference, it’s just not worth it for a single adjustable shock.

Same goes for the front shocks. I’ve seen enough cars unhook because the front end is so violent it it upsets the entire chassis.

And yes, most of them were 11 second cars.

You’re off to a good start. I think everything your doing/planning is spot on except for shocks.

FWIW I told my cousin the exact same thing, and he didn’t listen. The first time he went to adjust his Calvert’s I wasn’t there. He called me and asked what to do. I said IDK, what does turning the knob do to bump? The video says you need a stiffer bump setting, but no matter which way you turn the knob, you’re changing both bump and rebound. Call Calvert.

He played with it for a bit. Now he’s going order some DA Vikings for it.

He is the perfect example of not having the money to do it right once, but he has plenty of money to do it 2, 3 or 4 times (or not wanting to spend the money because he doesn’t see the difference between price and value).

Just one example of many I could cite. Spend once, cry once.
 
Most people are recommending Proforged for the ball joints. There are varying opinions on rubber versus polyurethane bushings. I would suggest you do a search on this forum and draw your opinion from that.
 
The best place to start is send the poly bushing back. Get the factory rubber and install them correctly. Never tighten the LCA or UCA while in the air . Have the LCA and UCA's mid way in their travel so they don't rip out of the casing. or have the car sitting on the ground at factory ride height. Worked best for me. I also put bump stop extensions on the uppers to eliminate travel. The car had quicker forward reaction.
 
My 1980 :eek: Direct Connection book recommends stock front shocks, of varying strength, depending on the e.t. Sounds old school. Without going straight to a high dollar shock (I'll get better shocks when I get the Calvert stuff), what's a good place to start?
I can’t give feedback on how good they are at the track or street (as I just installed them) but I went ahead and got the double adjustable QA1’s (with 324 possible damping settings) for the front (an old van with no other options for adjustable front shocks) Having experience setting up sport bikes with fully adjustable forks and rear shock I can already see the benefits of the doubles just in being able to set a baseline for drag strip, or comfortable drive, up to aggressive handling with tons of room to fine tune. As to service life, durability etc remains to be seen but I have to agree, do it once and be done.
 
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He is the perfect example of not having the money to do it right once, but he has plenty of money to do it 2, 3 or 4 times (or not wanting to spend the money because he doesn’t see the difference between price and value).

I too was like this but smartened up for the most part lol I'm still running Monroe front shocks I threw in that were recently purchase when the car was a six cyl. in my 440/500 Stroker. Car launches good and handles decent so I left them. I don't go to the track much.
 
I can’t give feedback on how good they are at the track or street (as I just installed them) but I went ahead and got the double adjustable QA1’s (with 324 possible damping settings) for the front (an old van with no other options for adjustable front shocks) Having experience setting up sport bikes with fully adjustable forks and rear shock I can already see the benefits of the doubles just in being able to set a baseline for drag strip, or comfortable drive, up to aggressive handling with tons of room to fine tune. As to service life, durability etc remains to be seen but I have to agree, do it once and be done.


Exactly. Guys who ride or have ridden dirt bikes and sport bikes know a DA shock is a must.


Nothing wrong with the QA1’s except the last time I looked they were a bit more than the Vikings. Either or will do.
 
Save your money onto Calvert shocks. You need something that is double adjustable. For the cost difference, it’s just not worth it for a single adjustable shock.

Same goes for the front shocks. I’ve seen enough cars unhook because the front end is so violent it it upsets the entire chassis.

And yes, most of them were 11 second cars.

You’re off to a good start. I think everything your doing/planning is spot on except for shocks.

FWIW I told my cousin the exact same thing, and he didn’t listen. The first time he went to adjust his Calvert’s I wasn’t there. He called me and asked what to do. I said IDK, what does turning the knob do to bump? The video says you need a stiffer bump setting, but no matter which way you turn the knob, you’re changing both bump and rebound. Call Calvert.

He played with it for a bit. Now he’s going order some DA Vikings for it.

He is the perfect example of not having the money to do it right once, but he has plenty of money to do it 2, 3 or 4 times (or not wanting to spend the money because he doesn’t see the difference between price and value).

Just one example of many I could cite. Spend once, cry once.
I totally agree on doing things once. But stock shocks are 26 a pair, and Vikings look to be between 350 and 400 a pair! THAT is a shocker!!:rolleyes: I wouldn't buy expensive single shocks for sure. I'll spend the DA money when I see how badly I need them, as Kendog 170 mentioned.
The best place to start is send the poly bushing back. Get the factory rubber and install them correctly. Never tighten the LCA or UCA while in the air . Have the LCA and UCA's mid way in their travel so they don't rip out of the casing. or have the car sitting on the ground at factory ride height. Worked best for me. I also put bump stop extensions on the uppers to eliminate travel. The car had quicker forward reaction.
Hi Steve, I hope that hood you came down for helped you out somehow.
Anyway, are stock bushings a personal preference, or do you feel they're quicker? Maybe the poly just isn't necessary? Years ago, I was a partner on a Stock Eliminator car. We used rubber, and left them loose with double nuts to make sure they were loose. I'm not sure I want a street car THAT loose. (The bolts were pivoting in the holes.)
Yeah, I tighten them at ride height.
As to limiting the travel, we did something similar. We used a small block bar on the passenger side, and a big block bar on the driver's side. That was after running the car a while, and experimenting. I'll try stuff like that on my car as I go.

Any more thoughts on ball joints? Proforged has an upper that's .5" longer than stock. Would that work w/o affecting geometry? Thinking about increasing travel, if necessary.

Thanks, everyone.
 
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I totally agree on doing things once. But stock shocks are 26 a pair, and Vikings look to be between 350 and 400 a pair! THAT is a shocker!!:rolleyes: I wouldn't buy expensive single shocks for sure. I'll spend the DA money when I see how badly I need them, as Kendog 170 mentioned.
Hi Steve, I hope that hood you came down for helped you out somehow.
Anyway, are stock bushings a personal preference, or do you feel they're quicker? Maybe the poly just isn't necessary? Years ago, I was a partner on a Stock Eliminator car. We used rubber, and left them loose with double nuts to make sure they were loose. I'm not sure I want a street car THAT loose. (The bolts were pivoting in the holes.)
Yeah, I tighten them at ride height.
As to limiting the travel, we did something similar. We used a small block bar on the passenger side, and a big block bar on the driver's side. That was after running the car a while, and experimenting. I'll try stuff like that on my car as I go.

Any more thoughts on ball joints? Proforged has an upper that's .5" longer than stock. Would that work w/o affecting geometry? Thinking about increasing travel, if necessary.

Thanks, everyone.
I am glad you replied. I found a home for the hood . My son is building a Nostalgia gasser. I lost your contact info. Is there anything I can help you with for your Duster. Are you selling that Fox body yet. I really liked that car. It was very well kept.
 
I’d look at the low friction upper ball joints that Speedway sells.
 
I am glad you replied. I found a home for the hood . My son is building a Nostalgia gasser. I lost your contact info. Is there anything I can help you with for your Duster. Are you selling that Fox body yet. I really liked that car. It was very well kept.
Glad to hear. Believe it or not, I have a list of the stuff I need. lol I'll get in touch as I go. I did get it running last October, and just finished putting the 9" and rear suspension in.
Thanks. Mustang's not for sale. I did get an 11.39 and 11.40 (@120 in super air) out of it before they asked me to leave and come back with a roll bar. As rarely as I race it, it's not worth the seatbelt upgrade every 2 years.

So, what do you think about the bushings?
 
I had problems with the poly bushings in my car. I will never use them or install them in any car that gets repaired here.
 
If the goal is low friction movement of the front end then stock bushings are not what you want, at least not everywhere.

Let me explain. The LCA bushings add a fairly significant amount of friction. Reason being is that nothing spins, when the LCA moves up and down that movement is translated into flex in the rubber LCA bushing- the pin does not move, the inner and outer bushing shells don't move, the rubber is friction fit to the shells so it doesn't spin- all the movement is the rubber bushing flexing. Which is why they have to be tightened at ride height, because if they're flexed entirely in one direction (like if they were tightened at full extension) they tear because the rubber doesn't have that much give. The rubber LCA bushing is literally built-in binding.

With a poly or delrin LCA bushing, the pin doesn't move, the shells don't move, and the poly does not flex. But unlike the rubber bushing, the poly bushing is not friction fit to the inner and outer shells, it's a tight slip fit. So, when the LCA moves up and down the poly bushing spins on the pin. Properly lubricated, the poly bushing creates very little friction. There's no limit for how far the LCA can move, unlike the rubber bushing which has limited flex and increasing resistance the further it's flexed. So the LCA pins can be tightened at any point in the install process, doesn't matter.

The "problem" with the poly bushings is that they MUST be lubricated. Which is why companies like Hotchkiss and Firm Feel sell greaseable pins. Poly is not rubber, different parts of the bushing move, and they still need to fit tightly in the shells and on the pin. Properly installed and maintained the poly bushings will outlast rubber every time. The problem is people don't check to make sure they fit properly on installation, they need to be a tight slip fit. If they're loose they'll either flop around in the outer shell or on the pin, both destroy the bushings. And then they must be lubricated, if they dry up the friction also damages them. It's not hard to do it right, it's no different than making sure the rubber bushings fit properly and not tightening them at full extension- it's just a different procedure. I have used them on several of my cars for tens of thousands of miles, all of them still look brand new. Bergman Autocraft's delrin LCA bushings solve the lubrication issue, delrin is self lubricating. So if you grease them a little on install they should last forever. They also take the place of the outer shell, so, less concerns about the aftermarket bushing fitting properly in the OE outer shell. I have BAC's delrin LCA bushings on my Duster. Next step up from poly, but more expensive too.

If you want to use the stock strut rods, I would suggest using rubber bushings there. Reason being that the strut rod also can cause binding as the LCA moves. The strut rod bushings deal with movement in two main directions, up and down as the LCA moves, but also forward and back as you brake and accelerate. The forward and back movement isn't ideal, that changes alignment settings and the softer rubber bushings allow a decent amount of movement there. But the up and down movement is necessary. The problem with poly bushings at the strut rod (other than the fact the most don't fit well) is that while they resist the forward/back movement better, they ALSO resist the up down movement. Which is not what you want.

If you want to further reduce binding, adjustable strut rods are very useful. They don't move forward and back like the stock strut rods with their large sloppy bushings. But, they allow free movement up and down, with even less resistance than the stock strut rods in that direction. And, they can be tuned for length. Which is important, especially with non-rubber bushings in other places. The factory depended on big fat rubber bushings to take up their production tolerances. Start eliminating those and the length of the strut rod becomes more critical. If the strut rod is too long or too short is can induce binding on the LCA. Again, not what you want. Which is why I use adjustable strut rods when I install poly or delrin LCA bushings. It's not mandatory, but, if you use the stock strut rods you will want to make sure they're the right length by checking the suspension for binding throughout its range of travel. The problem there is if they aren't the right length making them the right length is a lot more difficult.

If you do buy rubber LCA bushings, buy Proforged. Moog has recalls out now for their LCA bushings, the most recent batches don't even fit on the pins or in the LCA.

As far as the rest of the stuff for suspension set up, I'm not a drag racer. But the elimination of binding and having the suspension components move freely applies to handling cars too, it lets the suspension work properly regardless of what kind of driving the suspension has been set up for.
 
If the goal is low friction movement of the front end then stock bushings are not what you want, at least not everywhere.

Let me explain. The LCA bushings add a fairly significant amount of friction. Reason being is that nothing spins, when the LCA moves up and down that movement is translated into flex in the rubber LCA bushing- the pin does not move, the inner and outer bushing shells don't move, the rubber is friction fit to the shells so it doesn't spin- all the movement is the rubber bushing flexing. Which is why they have to be tightened at ride height, because if they're flexed entirely in one direction (like if they were tightened at full extension) they tear because the rubber doesn't have that much give. The rubber LCA bushing is literally built-in binding.

With a poly or delrin LCA bushing, the pin doesn't move, the shells don't move, and the poly does not flex. But unlike the rubber bushing, the poly bushing is not friction fit to the inner and outer shells, it's a tight slip fit. So, when the LCA moves up and down the poly bushing spins on the pin. Properly lubricated, the poly bushing creates very little friction. There's no limit for how far the LCA can move, unlike the rubber bushing which has limited flex and increasing resistance the further it's flexed. So the LCA pins can be tightened at any point in the install process, doesn't matter.

The "problem" with the poly bushings is that they MUST be lubricated. Which is why companies like Hotchkiss and Firm Feel sell greaseable pins. Poly is not rubber, different parts of the bushing move, and they still need to fit tightly in the shells and on the pin. Properly installed and maintained the poly bushings will outlast rubber every time. The problem is people don't check to make sure they fit properly on installation, they need to be a tight slip fit. If they're loose they'll either flop around in the outer shell or on the pin, both destroy the bushings. And then they must be lubricated, if they dry up the friction also damages them. It's not hard to do it right, it's no different than making sure the rubber bushings fit properly and not tightening them at full extension- it's just a different procedure. I have used them on several of my cars for tens of thousands of miles, all of them still look brand new. Bergman Autocraft's delrin LCA bushings solve the lubrication issue, delrin is self lubricating. So if you grease them a little on install they should last forever. They also take the place of the outer shell, so, less concerns about the aftermarket bushing fitting properly in the OE outer shell. I have BAC's delrin LCA bushings on my Duster. Next step up from poly, but more expensive too.

If you want to use the stock strut rods, I would suggest using rubber bushings there. Reason being that the strut rod also can cause binding as the LCA moves. The strut rod bushings deal with movement in two main directions, up and down as the LCA moves, but also forward and back as you brake and accelerate. The forward and back movement isn't ideal, that changes alignment settings and the softer rubber bushings allow a decent amount of movement there. But the up and down movement is necessary. The problem with poly bushings at the strut rod (other than the fact the most don't fit well) is that while they resist the forward/back movement better, they ALSO resist the up down movement. Which is not what you want.

If you want to further reduce binding, adjustable strut rods are very useful. They don't move forward and back like the stock strut rods with their large sloppy bushings. But, they allow free movement up and down, with even less resistance than the stock strut rods in that direction. And, they can be tuned for length. Which is important, especially with non-rubber bushings in other places. The factory depended on big fat rubber bushings to take up their production tolerances. Start eliminating those and the length of the strut rod becomes more critical. If the strut rod is too long or too short is can induce binding on the LCA. Again, not what you want. Which is why I use adjustable strut rods when I install poly or delrin LCA bushings. It's not mandatory, but, if you use the stock strut rods you will want to make sure they're the right length by checking the suspension for binding throughout its range of travel. The problem there is if they aren't the right length making them the right length is a lot more difficult.

If you do buy rubber LCA bushings, buy Proforged. Moog has recalls out now for their LCA bushings, the most recent batches don't even fit on the pins or in the LCA.

As far as the rest of the stuff for suspension set up, I'm not a drag racer. But the elimination of binding and having the suspension components move freely applies to handling cars too, it lets the suspension work properly regardless of what kind of driving the suspension has been set up for.

Write a book. It still doesn't make them a good investment . Proven many times on customers cars that come here from shops that install them. All I have to do is put their cars on the lift . Point one thing out and I get a job reinstalling Factory style rubber lowers and struts. Put a piece of poly and rubber in a vise squash them both and see what happens,. LOL. These suppliers can sell Ice to and eskimo in the Arctic . They should hire you.
 
Factory rubber bushings, and i love the CE 3 way shocks on the front. They work great on a street strip car
I had them on all 4 corners along with 002/003 s/s springs on a 9 sec N/A smallblock 70 Duster. Weighed 3350 with me, and would hook literally anywhere.
Plenty of guys on here know/ remember the car.
Doesn't take much at all to get a Mopar A body to work. I never even clamped the rear leafs.
A bodies have nice rear overhang and make great racecars. Don't overthink it.
If using Cal tracks, buy the 9 way rears Calvert makes, and the front CE 3 ways, like them better than the non adjustable Calvert 90/10 front
 
Write a book. It still doesn't make them a good investment . Proven many times on customers cars that come here from shops that install them. All I have to do is put their cars on the lift . Point one thing out and I get a job reinstalling Factory style rubber lowers and struts. Put a piece of poly and rubber in a vise squash them both and see what happens,. LOL. These suppliers can sell Ice to and eskimo in the Arctic . They should hire you.

Yes, you've made it clear multiple times that you don't understand how to properly install a poly bushing, or what normal performance from poly LCA bushings on these cars looks like. Apparently your customers don't either, because your little parlor trick that has no bearing on how the suspension works when fully assembled convinces them to pay you to install inferior parts. Your little trick is literally a scam, so its ironic you make jokes about selling ice.

Just because you've been doing something the same way your whole life doesn't mean it's still the best way to do it. Technology changes, aftermarket parts improve on the OE designs, and things that couldn't be done with these cars 40 years ago are now common. But if you don't have a good understanding of how things work, and are unwilling to learn new information, you stay stuck in the past.

The OE bushings, no matter how well installed, will add resistance and binding to the suspension- it's literally how the OE LCA bushings function. Properly set up with aftermarket bushings and parts, you can get the suspension to move freely without having anything loose.

No doubt plenty of fast cars at the strip run OE bushings, that's fine. The OP asked about setting his suspension up so it had "freedom of movement". I gave him information that would let him do just that. He can do whatever he wants, and I'm not going to argue with a stump.
 
My mom used to say, "Fight nice, kids"!
That being said, I appreciate all of the advice. I'm going down the middle as far as bushings go. I'm going to try out a few combinations of rubber and poly, and see what my combo likes. How's that for diplomacy? :)
I mentioned what I'm doing with shocks, for now anyway.
I ordered Proforged balljoints. I'll see what they look like.
Considering what 72bluNblu said about the strut rods, regarding freedom of movement, I'm going to look over aftermarket strut rods. They are more involved to install, so I'd put them in now. Have to look at the budget.
 
Yes, you've made it clear multiple times that you don't understand how to properly install a poly bushing, or what normal performance from poly LCA bushings on these cars looks like. Apparently your customers don't either, because your little parlor trick that has no bearing on how the suspension works when fully assembled convinces them to pay you to install inferior parts. Your little trick is literally a scam, so its ironic you make jokes about selling ice.

Just because you've been doing something the same way your whole life doesn't mean it's still the best way to do it. Technology changes, aftermarket parts improve on the OE designs, and things that couldn't be done with these cars 40 years ago are now common. But if you don't have a good understanding of how things work, and are unwilling to learn new information, you stay stuck in the past.

The OE bushings, no matter how well installed, will add resistance and binding to the suspension- it's literally how the OE LCA bushings function. Properly set up with aftermarket bushings and parts, you can get the suspension to move freely without having anything loose.

No doubt plenty of fast cars at the strip run OE bushings, that's fine. The OP asked about setting his suspension up so it had "freedom of movement". I gave him information that would let him do just that. He can do whatever he wants, and I'm not going to argue with a stump.

There is no proper way of installing junk. LCA bushings with poly are free. Up and down front and back they move very free.LOL.

Also the poly strut bushings don't have shear sleeves molded into them. Foot braking a car shears them off where they fit in the K member due to their crumbling effect. Yes I know they have inner sleeves that have to be used with 73 and up coarse thread rods. The bottom line is you can't make perfume out of ****. Well you can but it still smells bad in the end. We will never agree on this only because in reality they are a product that don't function as good for a long time as OEM.

If I remember correctly the last time I mentioned the shear sleeves. You posted a picture of the sleeve that slides over the strut rod that the bushing slides over . So you my friend do not have a clue what the hell you are talking about. I have been building suspensions for a very long time and tried all the new products.

I have see the downside of them all. Poly bushings are for the do it yourselfers that don't have the equipment to do it correctly. You know , push out the rubber . Leave the sleeves in and slide in the poly with a lot of lube. Don't forget to install those pins with grease fittings so you can keep on lubing them. So they move freely Up and down and front and back. End of story . Oh yeah whats with the name calling I thought that wasn't allowed. Ah but your special. You must know the moderators. "Stump" could mean a lot of things , You could have called me a tree. LOL

DSCF0224.jpg


susp2.jpg
 
My mom used to say, "Fight nice, kids"!
That being said, I appreciate all of the advice. I'm going down the middle as far as bushings go. I'm going to try out a few combinations of rubber and poly, and see what my combo likes. How's that for diplomacy? :)
I mentioned what I'm doing with shocks, for now anyway.
I ordered Proforged balljoints. I'll see what they look like.
Considering what 72bluNblu said about the strut rods, regarding freedom of movement, I'm going to look over aftermarket strut rods. They are more involved to install, so I'd put them in now. Have to look at the budget.
This is ongoing. I will never agree with him. My experience with poly was when I went up against the front wheels footbraking the Duster. The poly bushings crumbled and we saw pieces come out from under the car . I eliminated travel and increased my 60 ft . But it was only a mid 10 sec car.

 
Here's what I did to an OT car to free up the strut rods, just cut the stock rods and added some rod ends...

GSSshopmulefrontsuspension.jpg


Grant
 
There is no proper way of installing junk. LCA bushings with poly are free. Up and down front and back they move very free.LOL.

Also the poly strut bushings don't have shear sleeves molded into them. Foot braking a car shears them off where they fit in the K member due to their crumbling effect. Yes I know they have inner sleeves that have to be used with 73 and up coarse thread rods. The bottom line is you can't make perfume out of ****. Well you can but it still smells bad in the end. We will never agree on this only because in reality they are a product that don't function as good for a long time as OEM.

If I remember correctly the last time I mentioned the shear sleeves. You posted a picture of the sleeve that slides over the strut rod that the bushing slides over . So you my friend do not have a clue what the hell you are talking about. I have been building suspensions for a very long time and tried all the new products.

I have see the downside of them all. Poly bushings are for the do it yourselfers that don't have the equipment to do it correctly. You know , push out the rubber . Leave the sleeves in and slide in the poly with a lot of lube. Don't forget to install those pins with grease fittings so you can keep on lubing them. So they move freely Up and down and front and back. End of story . Oh yeah whats with the name calling I thought that wasn't allowed. Ah but your special. You must know the moderators. "Stump" could mean a lot of things , You could have called me a tree. LOL

View attachment 1715559018

View attachment 1715559019

This is ongoing. I will never agree with him. My experience with poly was when I went up against the front wheels footbraking the Duster. The poly bushings crumbled and we saw pieces come out from under the car . I eliminated travel and increased my 60 ft . But it was only a mid 10 sec car.



You're right, let's break this down into facts-

OMM- Has never installed a poly bushing that hasn't failed in a short period of time, according to him. That includes multiple brands of bushings, different applications, and even different vehicles if you read his responses.

72blu- Has never installed a poly bushing that has failed, in some cases that includes over a decade of use and tens of thousands of miles. That also includes multiple brands of bushings, different bushing applications, and vehicles.

If you eliminate the brand of the poly bushing, the application, the use, and even the vehicle they're installed in, you've eliminated every commonality between all of those poly bushings except for one. The guy that installed them. That's the only thing in common between all of the failed poly bushings that OMM has installed. All of them failed, and all of them were installed by the same guy. Literally nothing else is the same, and that's according to him.

I've never had a poly bushing fail. I'm not saying in the history of poly bushings that a bad one has never been made, but none of the ones I've installed has ever failed. Heck so far none of them have even worn out, although I'm sure they will eventually. I've used them on classic cars, I've used them on modern cars, I've used them on 4wd trucks. I've used poly LCA bushings, poly sway bar bushings, poly radius arm bushings, poly cab and body mounts, etc. Some of those bushings have been on my vehicles for over a decade.

Yes, there are applications where I wouldn't use a poly bushing, like on the strut rods of these cars for the reasons I explained earlier. If you understand how the bushing is supposed to function, and you understand how the material works in that application, you can intelligently decide what materials will improve performance in that application and which ones won't. If you don't understand that, you're just slapping parts together and hoping things work.

Clearly, I'm not the only person here that has successfully installed a poly bushing. And I know that they won't last forever and they're not right for every application, but the same is true of rubber bushings.
 
You're right, let's break this down into facts-

OMM- Has never installed a poly bushing that hasn't failed in a short period of time, according to him. That includes multiple brands of bushings, different applications, and even different vehicles if you read his responses.

72blu- Has never installed a poly bushing that has failed, in some cases that includes over a decade of use and tens of thousands of miles. That also includes multiple brands of bushings, different bushing applications, and vehicles.

If you eliminate the brand of the poly bushing, the application, the use, and even the vehicle they're installed in, you've eliminated every commonality between all of those poly bushings except for one. The guy that installed them. That's the only thing in common between all of the failed poly bushings that OMM has installed. All of them failed, and all of them were installed by the same guy. Literally nothing else is the same, and that's according to him.

I've never had a poly bushing fail. I'm not saying in the history of poly bushings that a bad one has never been made, but none of the ones I've installed has ever failed. Heck so far none of them have even worn out, although I'm sure they will eventually. I've used them on classic cars, I've used them on modern cars, I've used them on 4wd trucks. I've used poly LCA bushings, poly sway bar bushings, poly radius arm bushings, poly cab and body mounts, etc. Some of those bushings have been on my vehicles for over a decade.

Yes, there are applications where I wouldn't use a poly bushing, like on the strut rods of these cars for the reasons I explained earlier. If you understand how the bushing is supposed to function, and you understand how the material works in that application, you can intelligently decide what materials will improve performance in that application and which ones won't. If you don't understand that, you're just slapping parts together and hoping things work.

Clearly, I'm not the only person here that has successfully installed a poly bushing. And I know that they won't last forever and they're not right for every application, but the same is true of rubber bushings.

They are failed as soon as you install them.

Once a OEM lower is ripped off of the shell the LCA moves front to back off of the pin then the are bad. The car wonders on uneven roads. This usually accurs when you tighten the pin nut while in the air using OEM style.

Poly bushings do that as soon as they are installed. And then you lube them. It has nothing to do with installation it is the design. What Holds the LCA on the pin? Only the OEM bushing . Not the poly style lubed.

Put the car in reverse and hold your foot on the brake . Apply the throttle and watch the LCA move off of the pin. Its even worse with the adjustable struts.

On the subject of poly struts. take them off after some miles and see if the protrusion that goes through the K-member is still there. They have no shear sleeve molded into the poly bushing. I try to use only rubber with the shear sleeve molded in. But even the cheap rubber without the shear sleeve last longer then the poly. They do not like friction or crush they are to stiff and crumble. Been doing these cars since the 70's. I tried them all.

We do a lot more then suspension here and have everything to do any type of work. Motors, frames , and anything needed on any type of car. Some places and some cars poly is the way to go . Just not on mopar LCA's or struts. We actually did away with the strut bushings and were working on putting bearings in the lowers on our car.

All your doing is making a fool out of yourself to many members that come here. I use this post to advertise for work. This is one of many.


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I can jump on the band wagon on either side.
I have ran urethane upper and lower control arm bushing for 20 year with out one fail Stock strut rod bushing.(right side was shot)

Or i can say that these urethane bushing failed because they got real stiff and squeaky. Took 140 pound of pressure to push up a 60 pound suspension w/out shock and t-bars installed.

Rebuilt front end with Hymns joint upper control arms, re greased the urethane lower control arm,(was still good) and added a hymns joint front strut rod.
Took 65 pound of pressure to raise the suspension.
Free the front end right up.

one note: there has been talk of Hyms strut rods heaving premature ware on a street car. mine only sees track life. mine only a few month old so time will tell.
 
Save your money onto Calvert shocks. You need something that is double adjustable. For the cost difference, it’s just not worth it for a single adjustable shock.

Same goes for the front shocks. I’ve seen enough cars unhook because the front end is so violent it it upsets the entire chassis.

And yes, most of them were 11 second cars.

You’re off to a good start. I think everything your doing/planning is spot on except for shocks.

FWIW I told my cousin the exact same thing, and he didn’t listen. The first time he went to adjust his Calvert’s I wasn’t there. He called me and asked what to do. I said IDK, what does turning the knob do to bump? The video says you need a stiffer bump setting, but no matter which way you turn the knob, you’re changing both bump and rebound. Call Calvert.

He played with it for a bit. Now he’s going order some DA Vikings for it.

He is the perfect example of not having the money to do it right once, but he has plenty of money to do it 2, 3 or 4 times (or not wanting to spend the money because he doesn’t see the difference between price and value).

Just one example of many I could cite. Spend once, cry once.

And here's our first time out with new combo doing just that, tops and unloads them>

and funny enough that was our quickest of the day a 10.5@125.83
 
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I can jump on the band wagon on either side.
I have ran urethane upper and lower control arm bushing for 20 year with out one fail Stock strut rod bushing.(right side was shot)

Or i can say that these urethane bushing failed because they got real stiff and squeaky. Took 140 pound of pressure to push up a 60 pound suspension w/out shock and t-bars installed.

Rebuilt front end with Hymns joint upper control arms, re greased the urethane lower control arm,(was still good) and added a hymns joint front strut rod.
Took 65 pound of pressure to raise the suspension.
Free the front end right up.

one note: there has been talk of Hyms strut rods heaving premature ware on a street car. mine only sees track life. mine only a few month old so time will tell.
The hymes on ours are for a track car. The problem I have seen with the poly LCA's is the arm moves front and back. Very noticeable when you put the car in reverse and hit the brakes. What does that do when foot braking the car and leaving off the brake . We saw that the only thing holding the LCA forward. is the torsion bar and the clip. I have seen race cars with them on and they drill the torsion bar socket at the rear and put a bolt through. But just relying on the clip with shims is not the way to go.

No one ever thought it through on the LCA moving front to back with poly bushings. The OEM if installed and tightened at ride height don't rip. If they are tighten at the lifted position then let the car down the rubber helps lift but when the rubber breaks free from the sleeve its shot. Because it allows forward and rearward movement. Put your car on the lift and pry the arm back at the K-member with poly bushings it moves front to back at least 1/2 to 3/4 inches.

As far as the struts, Without the shear sleeve the K-member gets ruined. This is the reason they went to the two piece bushings with the molded steel in them. Some replacement rubber strut rod bushings don't have the sleeve either. But the rubber is more forgiving then poly when used and last longer. I have not taken a set of poly off yet that the male nipple that seats in the K-member wasn't gone. I didn't install them they were installed by other shops and owners. The cars come here because the steering wanders on our PA. wavy bumpy and **** roads . I agree that when you look at the bushings on cars installed they look fine . Take them off and inspect them you will see the bushings are wore and tore. No one will ever change my mind on what I have seen with my own eyes. I will never install poly on lowers or struts.

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