SPL install tips

[suicidaleggroll]

I recently installed the full set of SPL arms on my car, and I was surprised to find very little information here on them. Lots of people running them, but basically nothing on the install process, tips and tricks, etc., so I figured I would make one. This isn't a step-by-step install guide, SPL already has those, this is more for people to offer their own suggestions on things they ran into or had to figure out themselves.

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[suicidaleggroll]

Front LCAs:

The installation was pretty straight forward, nothing jumped out to me as missing from SPL's docs, but I did find that separating the leveling sensor on the driver's side from the stock arm SUCKED ASS. Nothing I did worked, the plastic bracket on the factory LCA snapped almost immediately when I started trying to separate them (no biggie, I wasn't planning on reinstalling the factory arm anyway), and every time I tried to use something to pry or pull the ball out of the socket it just broke more. What finally worked for me was to zip-tie the factory arm to a 13mm wrench for reinforcement with the open end of the wrench positioned carefully to support the opening on the arm while still letting the ball pull free, use a set of locking pliers to grab onto the ball, position the arm behind the strut to hold it steady, and then pull full force on the pliers. When the ball finally pulled out of the arm I tumbled backward into the wall, but it came out and the arm was still in one piece! See the pics below for more clarity.

The new leveling sensor bracket on the SPL arm is kind of janky as well. It doesn't bolt to the arm anymore, instead it just kind of loosely fits over the threaded portion of the arm to hold it in place. It positions the sensor well, I haven't had any error codes yet, but it's very loose and rattles around. I zip-tied it down to keep it still, but I'm curious if anyone else has other suggestions.

Also as many people have pointed out, the clearance between the LCAs and the sway bar is very small. Using adjustable endlinks set as short as they can will help buy some extra room, and in my case I also decided to cut off the 3rd adjustment hole, so now I only have 2-way adjustable front sways. Cutting it off was pretty straight forward, just a hackzall to cut through the center of the hole, then an angle grinder to take off the remaining 1/8" or so and round/smooth it out, then some rustoleum paint to clean it up.

It's impossible to get these set exactly the same as OEM, so just ballpark it and then get an alignment ASAP.

SPL provides multiple spacers to adjust the roll center, but doesn't provide any guidance on how to set it. My car is on HKS adjustables at roughly the default height, so about a 1" drop. I used the thick spacer by itself, so about half of the total adjustment range. I don't have a ton of miles yet on them, but so far so good.

Note that my picture of the arm installed was before I rotated it properly. It's a bit too angled in this pic, it sits more vertical in real life, similar to the pic in SPL's install doc.

 

[suicidaleggroll]

Front Tie Rod Ends:

Super easy install, nothing was problematic. The SPL docs say to mark the tie rods so you know how far to thread the SPL ends on, and while I guess that's an ok starting point, it was still WAY off for me. I had probably 3-4 degrees of toe-out on both sides initially, and had to turn another 5 threads or so into the SPL ends to get the wheels straightened up. Luckily adjusting toe on the front is really easy, just loosen up the SPL clamp and then turn the factory tie rod with a 15mm wrench.

I didn't have anything to actually set the toe properly, so I just eyeballed it by looking down the outside edge of the front tire like a gun sight and adjusting the toe until this put it roughly in line with the outside edge of the rear tire. The result won't be great, but it should get you within a degree or so, which is good enough to drive a few miles to get a proper alignment.

Also, SPL mentions they have spacers to adjust bump steer, but never says anything about how to set it. As I mentioned before, my car is on HKS adjustables at roughly the default height, so about a 1" drop. I used the thick spacer by itself, so about half of the total adjustment range. I don't have a ton of miles yet on them, but so far so good.

 

[suicidaleggroll]

Rear Traction Links:

Pretty easy install, nothing was too challenging. This is a good first arm to get your feet wet. And as long as you set the length the same as the factory arm, you don't really need to get an alignment for it either. I did this arm first, and it cleaned up most of my wheel hop all by itself. It's a good addition even if you don't install the rest.

 

[suicidaleggroll]

Rear Toe Arm with Toe Lockout Kit:

Really easy install, SPL's docs cover everything pretty well. They do suggest putting the toe lockout bolt in from the rear so the nut is hidden inside the subrame though. I didn't like that, I was too worried about dropping the lockout bracket or nut inside the subframe, so I did it the other way. Place the lockout bracket on the bolt, slide the bolt in from the front toward the rear through the subframe first, adjust the length of the toe arm until the lockout bracket settles into place between the raised bumps on the subframe, then place the lockout bracket on the other side, play with the toe arm length a bit until that one settles into place as well, then put on the nut and torque. These arms absolutely need an alignment, don't install this until you already have an appointment booked and don't drive anywhere except directly to the shop.

 

[suicidaleggroll]

Rear Upper Arms:

This install sucked, mainly because you have to drop the subframe to get one of the bolts out. Cusco's rear sway install doc is a really good guide for dropping the subframe:
https://assets.ctfassets.net/fmj32k...22_rear_sway_bar_2020_toyota_gr_supra_a90.pdf

To that guide I would just add that you'll want to place some jackstands under the rear subframe mount points once you've dropped it the necessary 3-4" (the lower two points marked (12) in that doc on step 12). When you drop the subframe, the ONLY thing holding it up is your jack on the diff, which means when you start wrestling with these 100+ ftlb bolts on the arms, the subframe starts swinging around pretty wildly. The jack stands under the mount points will help keep it stable so it doesn't end up falling off the jack and ruining your day.

Also, the rear camber arms are very curious. For some reason that I don't understand, instead of using the normal spacers on each side of the rod ends, SPL chose to use a different type of spacer with an o-ring on one side of one end. Their install doc calls it a "Headlight Limiting Spacer", but this is on the rear upper arm and has absolutely nothing to do with the headlight leveling sensor. Additionally, every image shows it in a different place, the diagram in the install doc shows it on the subframe end, the picture on their site shows it on the knuckle end, and other than the install doc labeling it in the diagram, it's literally never mentioned anywhere in the installation steps. I have no idea what this spacer is for or where it's supposed to go. I just left it positioned exactly as it came on the arm in the package from SPL.

Like the rear traction links, these arms don't really need an alignment either. It's easy to set them to the same length as the OEM bars. Once you're done with everything it would be a good idea to get one, but feel free to install these a few weeks early to get them out of the way.

 

[suicidaleggroll]

Rear Camber Lockout Kit:

This one is deceivingly difficult. It looks like it should be easy, it's just one bolt, but it's kind of rough. This bolt goes on the subframe end of the lower control arm in the rear (the big fat OEM arm that the strut, spring, and knuckle all mount to). There are no installation instructions on SPL's site for this part. It does come with some in the box, but they're very hand-wavy and vague. To install this, you'll want to completely disconnect the lower arm in the rear, both the knuckle and the strut. When you then pull the factory eccentric bolt out the arm will be free, allowing you to position it correctly to get the lockout plates in place.

The lockout plates are not symmetrical, the hole is offset. The install docs say this is so that you can position the hole toward the center of the car for minimum camber, or toward the outside of the car for maximum camber. It does not tell you what "minimum" or "maximum" mean though. I initially set them for maximum camber, but that was a mistake, the alignment shop had to flip them to minimum to dial things in. What they found with the car on the machine is that with all of the other arms set to factory length, with this lockout kit set to maximum camber I was getting about -4.5 degrees in the rear, and with it set to minimum camber I was getting about -1.0 degrees. Additionally, setting them to maximum camber also dropped the rear end of the car about 0.5". Between the drop and the nearly 5 degrees of camber I was hardcore tucking the rear tire on the way to the shop. Once they flipped it to minimum (holes toward the center of the car), the ride height popped back up to where it should be, and they were easily able to dial me in to -2.1 degrees in the rear using the other arms.

Also I'm not sure where to put this so I'll just leave it here. This was probably the 7th or 8th time I've had to disconnect this lower arm from the spindle, and after about the 3rd time fighting it trying to get the bolt back through the control arm and the spindle, I finally figured out a better way. When you try to bolt the spindle back to this lower arm, they're often way out of alignment. You can usually use a screwdriver or something to rotate the bushing on the spindle to get the bolt halfway through, but getting it the rest of the way is often a challenge. What I finally discovered is that the E-Torx sockets actually fit tight enough to the bolt that you can use it as a lever arm. Plug a 6" extension into your E-Torx socket and put the socket on the head of the bolt once you've managed to get it through halfway. Then while watching the other side of the control arm, use the 6" extension as a handle to pivot the bolt around until the holes line up, then take a dead-blow hammer and tap the end of the extension to push the bolt through. The first few times I had to bolt the spindle back onto the control arm it took a good 15-20 minutes per side, now it takes 15 seconds.

 

[suicidaleggroll]

And just for fun, here's the alignment results for a "spirited street" setup. Somehow I ended up with slightly unbalanced caster, I'm considering getting the adjustable caster bushings to be able to clean that up, but in the mean time it'll be fine. The zero toe up front makes it walk a bit on the freeway, it'll take a little getting used to but so far it's not bad.

 

[kappa_md]

Thanks for these tips. Really appreciate it. Just have a few questions.
1. Did you change also to SPL adjustable end links front and rear?
2. What springs are you using? And I noticed you have different front and rear sway bars?
Thanks for your help!

 

[suicidaleggroll]

Thanks for these tips. Really appreciate it. Just have a few questions.
1. Did you change also to SPL adjustable end links front and rear?
2. What springs are you using? And I noticed you have different front and rear sway bars?
Thanks for your help!

Yes I’m running F/R SPL endlinks

HKS adjustable springs, Eibach front sway on the middle setting, Cusco rear sway. I would have done Eibach rear to match the front but they were on a lengthy backorder so I decided to go with Cusco instead to keep things moving.

 

[kappa_md]

Yes I’m running F/R SPL endlinks

HKS adjustable springs, Eibach front sway on the middle setting, Cusco rear sway. I would have done Eibach rear to match the front but they were on a lengthy backorder so I decided to go with Cusco instead to keep things moving.

Thank you! I’m running the whole Eibach ProPlus combo (springs and F/R sways) I also got the new released Eibach Pro Alignment (rear camber arm) It’s the only adjustable arm available from Eibach that’s why I’m looking into getting the other SPL parts. A good geo and alignment tune is crucial for me to extract most out of the GR Supra without adding crazy power.

 

[FuzzyRev]

Thanks for this, very helpful!

Personally I don't track the car yet, and didn't feel the need for any of this stuff, but the traction bars are starting to look like something I'd benefit from if they make a difference in wheelhop/shudder.

 

[Nocturnal LE]

Rear Traction Links:

I did this arm first, and it cleaned up most of my wheel hop all by itself. It's a good addition even if you don't install the rest.

So did you drive the car for a while with just the rear traction links? I'm curious the differences you noted driving with only rear traction links vs. all the other rear components.

 

[suicidaleggroll]

So did you drive the car for a while with just the rear traction links? I'm curious the differences you noted driving with only rear traction links vs. all the other rear components.

Yeah there was about a 2 month gap between doing the rear traction links and then doing everything else. The biggest difference was that they pretty much eliminated the wheel hop. The general uneasiness/unsettled feeling when hitting bumps mid-corner didn't really disappear until I did the rest of the arms though.

 

[decodeddiesel]

I'm going to be tackling this install soon, and there's a lot of very useful knowledge here. Thanks for sharing!

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