Benefit of Dynamic Strut Rod (and other Suspension Q’s)

Joeycurl said
Which adj strut rod would people prefer Hotchkiss, QA1, FirmFeel, or PST? I am in the market for one and leaning toward Hotchkiss.... since its made from steel vs AL

I prefer the QA1. You don't need steel strut rods for strength, it just adds weight. The purpose of the strut rods is just to keep the LCA from moving too far forward or back under braking/acceleration, they do not support the weight of the car. I have over 70k street miles on the aluminum CAP (bought out by QA1) strut rods on my Challenger. They also use a double adjuster, so tuning the length is much easier than with the other styles that use a bolt through the LCA end.

RogerRamRod said
@72bluNblu , Question for you. I notice my torsion bar mount front & rear, and strut rod bushing (rubber pivot point) all line up. I have RMS strut rods ready to go on the car when I start assembly. The pivot point on the RMS rods is further back and outboard of the hole in the K frame. Not by much, but if we are talking about smooth, bind free travel, a different arc is a different arc.
The hole in the K frame/rubber bushing IS the pivot point in the factory design. The RMS piece is a bolt through some solid bushings at the K frame, then a bracket that holds a heim joint, then the joint itself.
I haven't gotten as far as assembly yet to feel it as it swings up & down, so I could be concerned about nothing, but I've been cycling this through my mind for way too long.

Yes, adjustable strut rods have a slightly shorter effective length than the factory strut rods. They're all slightly different, but basically the way the heim is mounted on every design out there moves the pivot point back from the factory location.

But the holes being "lined up" is irrelevant. The factory strut rod and the LCA are not the same length, and their arcs are still at an angle to each other. So even if they were the same length (they are not), the paths still diverge. And get this, the pivot point on the factory strut rods can move. The rubber bushings stretch and compress under braking and acceleration loads, and that means the pivot point is not always centered between the washers.

Here's the deal, and I don't care what other members have said here. I have never had an issue tuning the length of the adjustable strut rods on my cars so that there was no binding within the range of the suspension travel. Don't get me wrong, the end of the strut rod and the end of the LCA trace out different arcs, which means if they travel far enough they will absolutely bind. But within the range of travel of the suspension on my cars I've always been able to adjust the length of the strut rod so there was no binding between the bump stops.

chinze57 said
Been a while since I’ve been on the site. I ended up going with the BAC lower control arm boxing kit, the torsion bars they had, the strut rods (which I believe are QA1, forgive me if I’m wrong I’m not looking at the part right this second).
I got tubular UCAs from PST, which required picking up a new brake kit from doctordiff. I made a mistake when ordering which was entirely my fault, I jumped the gun when I should have waited for a reply and done more research, so thank you to the person at doctordiff who was patient and helped me out.
I also have installed Bilstein shocks front and rear. What I can say about all of this is, it’s tightened a lot of stuff up. I can corner no issue, even with 24:1 power steering. There’s no sway bar in the front or rear but there’s not really much body roll in the front with the thick torsion bars. I highly recommend the change.
I need to get new leaf springs for the rear, I’m thinking 5 or 6 leaf, but can’t decide. Right now if I hit a bump, for a few seconds theres a bounce coming from the back, I think it’s because there’s such a difference in the stiffness front to rear.

The spring rate and the arch is much more important than whether the spring is a 5 or 6 leaf. Most of the performance handling springs are close to zero arch, with a spring rate around 130 lb/in. That's what you're looking for.