Adjustable upper control arm opinions.

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tcanin00

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I would like some advice on whether or not to run Gen I or Gen II SPC adjustable UCA's. I currently have a set of tubular PST's on it now, and am maxed out on adjustable and not really where it needs to be for decent alignment. The car is a 1970 Dart Swinger with a 318, and I'm running early 2000's Mustang Mach I 17×7 wheels. I forget the tire size, it's around 235 or 245 wide.
The intended use is a daily driver that might see some autocross in the future.
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Edited to add, it has a QA1 tubular K member, PST 1.08 torsion bars, and M body steering knuckles.
 

I haven't checked recently because I put the UCA's on almost a year ago. I think the driver's side was -.5* camber and then passenger side was -.25*. I didn't measure caster since I was out of adjustment. I believe the left side had more caster because it would correct itself from a left turn. Toe-in was 1/16th. Ride height is about a 1/2" under factory specs.
 
you need to find out what the current caster is. doesn't pst build caster into their arms? should be able to get a good alighnment with them.
 
I agree with everything so far, we'd need to know where you're at now and realistically you should be able to get decent alignment numbers out of the UCA's you already have.

That being said, you can definitely get more positive caster with a set of SPC's, and the fact that they're double adjustable makes setting the alignment quite a bit easier.

As for which is better, the GenI or GenII SPC's, that's a pretty fine point. Both are double adjustable, so either one should be more than capable of getting some pretty extreme alignment numbers. The GenII's with their forged construction look to be a more durable set up, with fewer bolted connections. Not sure how relevant that is because the UCA doesn't carry a ton of load. They also come with a 1/2" extended ball joint, which it seems like in most applications is going to give you a better caster/camber curve. They have an SPC ball joint, which is rebuildable etc but can only be had from SPC as far as I'm aware.

The GenI's have a couple extra connections built into their design, and they run a standard Mopar upper ball joint (the later LBJ for 73+). The adjuster is the entire UCA arm, so it's actually a little easier to get to than the GenII's because the adjuster is further away from the frame.

And of course the GenI's seem to be almost half the price of the GenII's, but they typically come without upper ball joints so that's an added cost.

I've been running the GenI's on my Duster for years now without any issues, and I run it around at -1° camber, +6.5° caster and 1/16" toe. With lots of adjustment to spare. I have a set of GenII's that will probably replace the Hotchkis UCA's on my Challenger when it goes back together.
 
To answer the OP's original question, I run the SPC double adjustable UCA's 1.0 (gen 1). Got them through Peter at @BergmanAutoCraft . They were easy to install and make setting whatever alignment specs you want a breeze. Highly recommend them!!
 
To answer the OP's original question, I run the SPC double adjustable UCA's 1.0 (gen 1). Got them through Peter at @BergmanAutoCraft . They were easy to install and make setting whatever alignment specs you want a breeze. Highly recommend them!!
You beat me to it. That guy is a God send to the Mopar community. We need to support him all we can.
 
Doesn't pst build caster into their arms?
Uhhh, they are supposed to.
A few months back, a fellow FABO friend and I installed PST UCAs in his 68 Dart. The right UCA was jigged and welded wrong. We could not get it any better than 1 degree NEGative caster! The left side was fine, the right was messed up. The stock UCAs both got 1/2 degree of negative camber and 3 1/2 degrees of POSitive caster so it wasn't a bent strut rod, LCA, damaged mounts....it was the PST arm.
Yeah, he got a refund.
 
Uhhh, they are supposed to.
A few months back, a fellow FABO friend and I installed PST UCAs in his 68 Dart. The right UCA was jigged and welded wrong. We could not get it any better than 1 degree NEGative caster! The left side was fine, the right was messed up. The stock UCAs both got 1/2 degree of negative camber and 3 1/2 degrees of POSitive caster so it wasn't a bent strut rod, LCA, damaged mounts....it was the PST arm.
Yeah, he got a refund.

crazy.. when o was looking up those links i found a ton of poor reviews on different stuff they sell.
 
I have PST parts in a couple of cars here. Those Dart control arms are the first I have seen that were screwed up like that.
 
you need to find out what the current caster is. doesn't pst build caster into their arms? should be able to get a good alighnment with them.
I'm working on it now. I noticed a lot of wear to the inside left front tire and the car felt very loose and wandered around.
So far, I found both adjustable strut rods were loose. The left was loose at the K member and the right at the lower control arm. After tightening them, I made sure the LCA's were parallel from the pivot bolt.
 
I agree with everything so far, we'd need to know where you're at now and realistically you should be able to get decent alignment numbers out of the UCA's you already have.

That being said, you can definitely get more positive caster with a set of SPC's, and the fact that they're double adjustable makes setting the alignment quite a bit easier.

As for which is better, the GenI or GenII SPC's, that's a pretty fine point. Both are double adjustable, so either one should be more than capable of getting some pretty extreme alignment numbers. The GenII's with their forged construction look to be a more durable set up, with fewer bolted connections. Not sure how relevant that is because the UCA doesn't carry a ton of load. They also come with a 1/2" extended ball joint, which it seems like in most applications is going to give you a better caster/camber curve. They have an SPC ball joint, which is rebuildable etc but can only be had from SPC as far as I'm aware.

The GenI's have a couple extra connections built into their design, and they run a standard Mopar upper ball joint (the later LBJ for 73+). The adjuster is the entire UCA arm, so it's actually a little easier to get to than the GenII's because the adjuster is further away from the frame.

And of course the GenI's seem to be almost half the price of the GenII's, but they typically come without upper ball joints so that's an added cost.

I've been running the GenI's on my Duster for years now without any issues, and I run it around at -1° camber, +6.5° caster and 1/16" toe. With lots of adjustment to spare. I have a set of GenII's that will probably replace the Hotchkis UCA's on my Challenger when it goes back together
I'll get actual numbers soon. I don't have a lot of time to work on the car in the evenings.
You pretty much covered my concern of the construction of the Gen I's compared to the II's. I was worried about the strength of a bolted together assembly versus a forged unit. If the Gen I's have held up for you, I doubt I'll push my car to the point of needing the II's.
I would be more interested in the Gen II's if I had A body knuckles. From what I've read, the FMJ knuckles have better camber/caster curves in comparison. I'm sure a dedicated track car would benefit from as much as possible.
 
You beat me to it. That guy is a God send to the Mopar community. We need to support him all we can.
I try to support companies based on customer support and their involvement. I know Bergman is pretty active in the forums and listens to what his customers have to say.
 
Uhhh, they are supposed to.
A few months back, a fellow FABO friend and I installed PST UCAs in his 68 Dart. The right UCA was jigged and welded wrong. We could not get it any better than 1 degree NEGative caster! The left side was fine, the right was messed up. The stock UCAs both got 1/2 degree of negative camber and 3 1/2 degrees of POSitive caster so it wasn't a bent strut rod, LCA, damaged mounts....it was the PST arm.
Yeah, he got a refund.
I read your thread on the PST UCA's and that's what got me thinking about changing them for something better. I bought them used for what I thought was a deal. Now they're money lost on trying to be cheap.
 
You beat me to it. That guy is a God send to the Mopar community. We need to support him all we can.
Yeah when I burned up a couple of power steering pumps with the new Borgeson steering kit Bergman was right there the whole way until the issue was permanently resolved. Answered text messages on weekends and responded when he was at Moparty etc. When you buy from him you have someone there by your side should an issue arise. The guy knows customer service, is a big time mopar expert, and high problem solving aptitude that I can attest to.
 
Yeah when I burned up a couple of power steering pumps with the new Borgeson steering kit Bergman was right there the whole way until the issue was permanently resolved. Answered text messages on weekends and responded when he was at Moparty etc. When you buy from him you have someone there by your side should an issue arise. The guy knows customer service, is a big time mopar expert, and high problem solving aptitude that I can attest to.
I couldn't agree more. More vendors need to use him as a template.
 
I'll get actual numbers soon. I don't have a lot of time to work on the car in the evenings.
You pretty much covered my concern of the construction of the Gen I's compared to the II's. I was worried about the strength of a bolted together assembly versus a forged unit. If the Gen I's have held up for you, I doubt I'll push my car to the point of needing the II's.
I would be more interested in the Gen II's if I had A body knuckles. From what I've read, the FMJ knuckles have better camber/caster curves in comparison. I'm sure a dedicated track car would benefit from as much as possible.

Yeah looking back at my pictures I've had the GenI's on there since 2017, and they've done over 30,000 street miles since then behind a set of 275/35/18's with 1.12" torsion bars, Hotchkis shocks and a Hellwig sway bar. I haven't had any issues with the various bolted connections. I did have a jam nut loosen up once but that was likely my fault for not torquing it enough. And that wouldn't be any different compared to the GenII's.

The FMJ spindles do have better camber gain, I think Peter Bergman looked into it and came to the conclusion that a 1/2" taller ball joint would improve the roll center further on his car which I believe also runs FMJ spindles. That's really fine tuning stuff, for a street going car that's not a thing you're going to do and feel a difference.
 
Thanks for letting me know your experience with them.
I've posted this other places but should have added it here too. These adjustable UCA's took the avatar from being able to make a full pass at the track maybe about 60% of the time to a car that goes dead straight eery time. They solved a serious lack of positive caster problem for me.

Little wheelies and almost 120 mph passes - I don't have to think or worry about these parts that have been on the car for over 2-1/2 years. They've seen more street driving too than you'd expect from a car like this (another 50 mile round trip to a cruise coming up this weekend!) I have not had any of the jam nuts come loose and the parts look like the day I put them on. Would I do them again from Peter? 100% ABSOLUTELY!!
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Note that the avatar (72 Demon) has the 73+ front disc brake setup.
 
Yeah looking back at my pictures I've had the GenI's on there since 2017, and they've done over 30,000 street miles since then behind a set of 275/35/18's with 1.12" torsion bars, Hotchkis shocks and a Hellwig sway bar. I haven't had any issues with the various bolted connections. I did have a jam nut loosen up once but that was likely my fault for not torquing it enough. And that wouldn't be any different compared to the GenII's.

The FMJ spindles do have better camber gain, I think Peter Bergman looked into it and came to the conclusion that a 1/2" taller ball joint would improve the roll center further on his car which I believe also runs FMJ spindles. That's really fine tuning stuff, for a street going car that's not a thing you're going to do and feel a difference.
Thanks for letting me know your experience with them. Your car is definitely more set up for aggressive handling.
That's the deciding factor on Gen I vs. II. I'm not going to be pushing my car to it's absolute limits. A dedicated track car would benefit from from the improvement in roll center.
 
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