Bergman Auto Craft Delrin Bushings and Pivot Pin Pkg Special use code BAC10
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goldduster318
Overzealous Car Modifier
Thanks for the discount! Looking forward to getting the polyurathane squeaker out of the car
Let’s revive this thread.. I have new qa1 lower control arms on my 72 dart. Can I simply clean out the rubber bushing and leave the sleeve in place in the control arm and install the Delrins.
Or do I need to remove the bushing and sleeve in the qa1 and install the delrin bushing into the lca without a sleeve..
Or do I need to remove the bushing and sleeve in the qa1 and install the delrin bushing into the lca without a sleeve..
You need to remove the outer bushing sleeve from the QA1 LCA and install the delrin bushing without any sleeves
Bennoel 10
Well-Known Member
Do you need to press in the new delrin bushing the same way as the original style ?? Seems to simple and easy. Might have to try a pair.
No. They are a light interference fit
abodyjoe
Well-Known Member
put them in our dart back in june when i did all the work to it in preparation for sick66. wish they were 10% off back then..lol
feel/sound no different then the rubber that was in there ride and noise wise. nice pieces in my opinion.and that supplied lube is sticky as hell.
feel/sound no different then the rubber that was in there ride and noise wise. nice pieces in my opinion.and that supplied lube is sticky as hell.
Unfortunately, prices of materials continue to rise. I price my parts reasonably and offer the best customer service in this industry. Why people waste money on the Q arms makes zero sense to me. Get the most for your money with Bergman Auto Craft, your site supporter and contributor for over 15 years..
WOW.
Well, this is pretty simple. If you lower your car, the QA1 LCA’s allow almost an inch of additional suspension travel vs a stock LCA. So, you can directly lower your car a full inch without losing any suspension travel. That’s pretty important, as lowering improves suspension geometry on these cars but losing travel is not a good thing.
Yes, the current version of the QA1 LCA with it’s included bump stop will need some modification to do this, but the way the bump stop was added to the LCA makes it pretty simple.
And then they weigh about 8 lbs less, which is actually pretty substantial given their location.
I never had an issue with stock arms and 11/16" bump stops. Like I said, wasting money on a new arm with a rubber bushing is ridiculous. Stock arm, thin bump stops, reinforcement plates and our delrin bushings/pivots. I have tons of street miles, auto X and open track events as proof. Its not really a debate in my eyes...Save your money and buy the forged upper arms so you have a taller ball joint and the ability to run 7 degrees of caster while maintaining reasonable negative camber (-.5) which helps straight line tracking.
An inch of suspension travel makes a heck of a lot more difference then a delrin LCA bushing does vs a poly bushing when it comes down to handling. More travel means the wheels stay on the ground longer, lower CG means better handling.
Look I’ve run stock LCA’s with reinforcing plates and thin bump stops. Yes, they work, but at the ride height I run (a-b= 0) you lose suspension travel if you do that, it’s just a fact. And I’m running 3/8” bump stops and 1.12” torsion bars. I still use ALL of my suspension travel, which remains close to 5.5” of total travel at the wheels.
The QA1 LCA’s are absolutely worth the money. The difference in CG at a lower ride height improves handling. The suspension geometry at the lower ride height is better. And being able to maintain the factory amount of travel keeps the wheels planted longer. It would be nice if they didn’t come with rubber bushings, but I understand from a production standpoint why they do. It’s easy enough to change them out for poly bushings and those are cheap, or Delrin bushings which are not. And I’ve been running the QA1 LCA’s on my Duster for over 7 years now, with over 25,000 miles on them (and your Delrin LCA bushings) in that time.
Don’t get me wrong, I love your Delrin LCA bushings, and I run your SPC UCA’s with delrin bushings, your idler arm bearing, and more stuff I don’t even recall at the moment and have another set of SPC UCA’s to buy for my Challenger yet. But the QA1 LCA’s aren’t junk, and while they are expensive the benefits they add are absolutely worth the price of the LCA’s. Does everyone need them? Of course not. But not everyone needs SPC UCA’s or delrin bushings either.
I’m honestly kinda surprised you’re arguing against them, given that I know you understand the importance of ride height and suspension geometry for getting one of these cars to handle well, and they allow changes that improve both significantly without losing suspension travel which is also critically important on a handling car.
You mention, "if you lower your car", are you suggesting that just by going to QA1 LCA's I would be able to achieve that?
The QA1 LCA's don't lower the car by themselves. What they do, because of their lower height profile than the stock LCA's, is add about 1" of suspension travel (the new version now requires removal of the bump stop and boss to achieve this). That happens regardless of whether you lower the car or not.
When you lower one of these cars with the torsion bar adjusters, you lose suspension travel. It's just how it works, you're trading ride height for suspension travel. Depending on how much you lower the car and the size of your torsion bars, you may have some suspension travel to give up. So if you run larger diameter torsion bars and only lower the car a little bit, you can run a shorter than stock lower bump stop and maintain roughly the same travel. That works for about 1" worth of lowering (factory bump stop is 1 3/8" tall, you can replace it with a 3/8" one, viola!).
The factory ride height measurement is set between the bottom of the torsion bar anchor/adjusting lever and the ball joint (A-B). On most 2 door A-bodies that measurement is 1 7/8". My duster is at A-B=0. So to be at that height with the stock LCA's and a short bump stop I'd have lost around 7/8" worth of suspension travel at the wheel.
With the QA1 LCA's and a bump stop added to the frame horn on my car, I have pretty much the same suspension travel as stock. And despite using 1.12" torsion bars, I still use all of that travel even just on the street. So with factory arms and my ride height I'd either need even larger torsion bars, or I'd have to live with the suspension hitting the bump stops MUCH more frequently. Too frequently.
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That works for about 1" worth of lowering (factory bump stop is 1 3/8" tall, you can replace it with a 3/8" one, viola!).
This is not entirely true. Since the geometric relationship here is more of a triangle, the bumpstop distance is not exactly proportional to static wheel height.
This has been an interesting debate. If anyone wants to speak further, feel free to call me at the shop - 516.384.6438
This is not entirely true. Since the geometric relationship here is more of a triangle, the bumpstop distance is not exactly proportional to static wheel height.
This has been an interesting debate. If anyone wants to speak further, feel free to call me at the shop - 516.384.6438
It's proportional, it's just not equal. The travel distance at the bump stop on a stock LCA is a bit less than 60% of the travel at the wheel if I recall correctly, I did the math on it at one point.
But it's not an equal comparison between the stock progressive rubber bump stop and the button style poly bump stop either. The factory bump stop compresses quite a lot, so you're not really gaining an 1" of travel by going to the 3/8" bump stop. You're getting an 1" of travel where you're not in contact with the bump stop, but since the factory bump stop can compress so much compared to the poly bump stop you're not gaining an inch of actual travel.
Realistically you can compress the stock bump stop at least half its height. So, yeah, going from the stock 1 3/8" bump stop to the 3/8" bump stop probably gets you around 1" of travel at the wheel, because you're not actually netting 1" of travel between the rubber and poly bump stops at the bump stop because of the amount of compression you get with the rubber bump stop.
I tried to simplify my explanation earlier, but the travel discussion gets complicated when you switch from rubber bump stops that are progressive and compress substantially and can be used as part of the suspension travel over to poly bump stops that you don't want to contact very frequently because they don't have very much give at all. You're just using the poly stops to keep from going metal on metal, not as part of the travel.
I always admire the amount of time you put into your answers. Just remember, the audience for this is so small you can count the amount of active, pro touring style mopars on 2 hands...
I think it's important to make anybody stepping up their game aware of the consequences of increasing grip & lowering the ride height dramatically, and that hitting the bump-stops at the wrong moment can cause a loss of grip & control, & possibly an accident.
That's what caused the Mopar Action Green Brick to crash, Kevin Wesley was honkin' on it in a left-hander, when it hit the right bump-stop & pushed straight off the track. If You have serious rubber & the car dropped, a street car that may not be running T-bars as stiff & more likely to run into rough road conditions, has a greater chance of this happening while playing.
Wesley has some serious driving chops, if it can happen to Him, what are the likely results to an avg. shoe out on the road w/o that kind of experience.....just sayin'
That's what caused the Mopar Action Green Brick to crash, Kevin Wesley was honkin' on it in a left-hander, when it hit the right bump-stop & pushed straight off the track. If You have serious rubber & the car dropped, a street car that may not be running T-bars as stiff & more likely to run into rough road conditions, has a greater chance of this happening while playing.
Wesley has some serious driving chops, if it can happen to Him, what are the likely results to an avg. shoe out on the road w/o that kind of experience.....just sayin'
This is why we use the thin stops. I don’t think they ever did. They also ran the suspension higher because of shorter tires. They also didn’t have the alignment numbers we have today or the benefit of taller ball joints.
Ehrenberg has some chops but he has steadfastly stuck to the incorrect opinion that the use of the taller FMJR knuckle would cause upper ball joint failures. I doubt if he were proven wrong that he would admit it in public.
Is there still a discount on this part ?
I need them.
Well, I'm 'just sayin' that I'm not talking about E-booger or His tech, I'm pointing out what can happen if one doesn't pay attention to that clearance Clarence. The QA1's can give You more if needed, which was simply the 'why' when asked.
There's more Mopars set up for pro-touring than that here on FABO alone. Whether or not they're "active" by your definition is irrelevant. If you set a car up that way, you need to be aware of the balance between wheel rate, ride height and the amount of available suspension travel you've got. Sure, there are different levels to that, but slamming hard parts together is bad whether you do it on the street or on the track. Heck even just slapping set of 2" drop spindles on your car "just for looks" can be a problem, because you can bottom the tire into the inner fender if you're not checking your suspension travel.
Neither of my Mopars have been on the track yet, and somehow I managed to figure all this out. Heck the suspension travel and ride height is probably more critical on the street, on a nice smooth track I doubt I'd be bottoming my suspension at all. On the mountain back roads I drive, on the other hand, I need to make sure that doesn't happen a ton because the road quality on some of the roads I drive is pretty marginal and I do use all of my suspension travel still.
The original Green Brick ran stock upper and lower UCA's, offset upper bushings and stock lowers, 383 torsion bars and 225/50/15's on 15x8" wheels. They said they "lowered it as much as they dared", but made no mention of the lower bump stops. They ran it with 0° camber and only +2° caster initially, although in one of the later outings they went with -1.25° camber. I will say that you can't see any lower bump stop at all in this picture from the 12/96 article, and I would think you'd be able to see the top of a stock one if it was there.
While it was pretty novel for what it was at the time, a set of 245 or wider 200 tread wear tires makes the entirety of the suspension set up on the Green Brick obsolete. I think it's a good starting point for a nice handling street car if you want to keep 15" wheels, but that's about it.
Oh he was proven wrong, Bill Reilly's article in Mopar Muscle pretty much called out Ehrenberg directly. And it provided all of the geometry numbers to back it up too, comparing the geometry of the FMJ spindles to the stock 73+ A-body spindles. Ehrenberg has had opportunities to back track, like when he did the Liberty rear brake conversion more recently. Instead in that article he patted himself on the back for doing the original article where he made the erroneous FMJ claims, and made exactly zero corrections.
Exactly. Does everyone need the QA1 tubular LCA's? Absolutely not. Can they be an important addition for a car that's been significantly lowered to maintain a reasonable amount of suspension travel? Absolutely. I'd have to raise my ride height without them.
There's another LCA out there that provides even more suspension travel than the QA1's, the 73/74 B-body LCA's allow for even more travel. And a lower ball joint separate from the steering arms too. Takes some work to make it work though, especially with the strut rod mount. Firm Feel used to set up B-body LCA's for both A and E bodies back in the day, they stopped though and apparently didn't make very many. Some of it is diminishing returns though, I know on my car with the QA1 LCA's and short bump stop on the frame horn I'm on the stop at about the same time as the top of the tire kisses the bottom of the inner fender. More mods would be needed to actually make use of those.
DionR
Well-Known Member
Do you have any documentation on this? I remember seeing it years ago and have gone looking through my magazine collection for it but couldn't find it.
It's in the Mopar Action from 4/2011. The article is called "Downtime".
I remember that article. I can see the benefit for those that live where the roads are beat up.
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