Timeless Steel Upper / DGO Lower Control Arm Upgrade

Why upgrade?

The AC/DMC DeLorean has up to this point been on its factory control arms. When I originally restored the car, I boxed the lowers to prevent twisting / cracking which seemed to work fine for the limited miles the car was seeing on the road. The weakness of the factory setup made me a little apprehensive to really push the car. 

Weak and non-adjustable factory control arms

Attending the Holley High Voltage Experience in 2021 and 2022 had me interested in pushing the car a little harder - specifically to try the road course. I was not, however, comfortable with doing so on the factory control arms - even with them being boxed. 

Another reason for upgrading is I wanted more adjustability in the alignment. On the stock DeLorean, the camber and caster angles are not adjustable. In my opinion, the stock alignment specs were driven more to make the car easy to steer at lower speeds, than highway speed stability. I always felt the car was a little darty at speed - increasing caster angle would help here. 

I decided it was time to seek out aftermarket options for both upper and lower arms.

Choosing the lower control arms

Lower control arm options are easy. Both DPI and DeloreanGo sell essentially the same billet lower control arm option. I ordered the ones from DeloreanGo, mainly because they were in stock and a friend had good experience with them:

https://www.deloreango.com/uk/aluminium-lower-control-arms.html

https://deloreanindustries.com/delorean-31-front-lower-control-arm-kit-stainless-powder-coated/

Choosing the upper control arms

There are a few options in the market for upper control arms. They tend to fall into a couple categories - all new billet adjustable control arms or factory style arms with an adjustable ball joint. While mulling over what to do, Timeless Steel DeLorean released a third option. Timeless Steel worked with SPC suspension products to bring an adjustable upper control arm to the market. Since SPC is a trusted name in the suspension industry and I trust Timeless Steel, I bought a set:

https://www.facebook.com/timelesssteell

New sexy upper control arms

They're beautifully constructed and fully adjustable. The engineers at SPC increased the size of the top ball joint for added strength (more on this later). They're fully rebuildable and all parts are available anywhere that sells SPC products (Summit Racing, Jegs, etc). 

New goodies ready for the install

Tear down

Removing the suspension on the DeLorean is straightforward:

• Remove the front sway bar since it's tied into the lower control arms
• Remove the front brake caliper / bracket and zip tie the caliper off to the side to keep it out of the way.
• Disconnect the coil over / shock from the lower control arm
• Disconnect the tie rod from the steering knuckle
• Separate the lower ball joint from the upright assembly
• Remove the lower control arm by unbolting it from the suspension housing on the frame
• Separate the upper ball joint from the upright assembly
• Remove the upper control arm by unbolting it from the suspension housing on the frame

If you completed all the steps you should be left with the following - no control arms and ready for the new good stuff

Lower Installation

Installation is largely the reverse of the tear down with a couple exceptions however I'll walk through it all. To begin, I installed the lower control arm by bolting it into the car at the pivot point. 

If you're installing your shock from the bottom (as was designed), you won't need to do this next step

The lower control arm is designed to have shock/coilover inserted up from the bottom of the arm. Since I already had the coilover installed and I didn't feel like removing the tensioned coil spring, I decided to install my shock from the top side. My QA1 coil over bushings would not clear the topside in the lower control arm, so I had to make the bushings be a two piece affair. I have a well equipped home shop, so I used my Bridgeport, however even a hacksaw / chopsaw will do it. 

I narrowed the bushing so it would clear the opening from the top, then made smaller spacer bushings so when it was all assembled, everything would be correctly aligned:

Test fitting the new upper and lower

New alignment bushings installed in the lower. Noice the bushing is in two pieces

With the lowers bolted in, I assembled the support braces. This is a common upgrade to increase stability of the lower arm. From the factory, the only thing keeping the lower in position is the sway bar - which can cause the caster angle to change under deflection. These support braces are available from DeloreanGo, DPI, or in my case I just used off the shelf rod ends and turnbuckles purchased from Speedway

https://deloreanindustries.com/delorean-spec-front-lower-arm-support/

https://www.deloreango.com/us/front-lower-arm-support-kit-pair.html

Here's a document with links to everything you need to assemble the same DIY supports:

https://docs.google.com/spreadsheets/d/1OTT5g4P7PlL-PDinGlybfqHOWLPqg5lLr1wQb9Tx4uk/edit#gid=0

Lower is complete with the support arms installed

Upper Installation

The first step to installing the new Timeless Steel upper control arms is to modify the factory uprights to fit the new (stronger) upper ball joints. Timeless Steel includes a 7* taper pin reamer to accomplish this task. Let me assure you, this process is easy and shouldn't concern anyone. 

Mount the upright in a vice or similar support. Taper pin reamer goes into a cordless drill. Lubricate the reamer with an appropriate cutting lube - I used automatic transmission fluid - a staple for this sort of  thing. 

The key to getting this right is to take your time and go slow. I had the upper control arm handy so I would ream for a few seconds, then test fit. 

Repeat over and over until the ball joint protrudes enough through the backside of the upper arm that the castle nut will fully seat AND the cotter pin hole is exposed enough you can insert a cotter pin through it with the castle nut installed. 

This is how open the top of the hole was on my install, however it was a little tight. I increased this slightly to make the cotter pin install easier (the hole needs to be fully exposed with the castle nut torqued down.

Keep test fitting the ball join in the reamed hole. This isn't quite enough.

While this looks involved, it took less than 5 minutes per side. Go slow and keep test fitting.

Once the ball joint is fitting properly, it's time to move back over to the car. The rest of this process goes fast. 

Bolt the upper control arm to the car. The head of the bolt faces forward, with the nuts to the rear. Included with the upper control arm kit are several washers / spacers - these are for adjusting the upper position so it clears the shock tower. Test fit with no additional washers added and confirm the upper will clear the shock tower. The close point is front edge of the tower - you can sort of see it in the photo below. I needed one washer on the leading side of the control arm to fully clear. 

Notice the orientation in this photo. This is the driver side of the car. 

With the shimming out of the way, the rest of the install goes as follows:

• Confirm the brake line is BEHIND the upright before doing the next step
• Torque the upper and lower ball joints to the upright. 
• Install the cotter pins in the upper and lower ball join castle nuts. 
• Torque the upper and lower bolts to spec. 
• Timeless Steel includes a printout from SPC that steps though the torque procedure. I highly recommend investing in a torque wrench - it's far better than trusting torquing "by feel". 
• Torque the tie rod to the steering knuckle
• Install the cotter pin on the tie rod castle nut
• Reinstall the front brake caliper + bracket
• Reinstall the front sway bar
• Grease the upper and lower ball joints with a few pumps of quality grease
• Install front wheels

You're all set! The remaining piece is to align the car. Now that you have the adjustability you can tune the alignment specs to your liking. I'm running about +4.5* of caster and -1* camber on each side, but that is subject to change as I get more miles on the car. 

Conclusion

I highly recommend both the lower control arm from DeLorean Go and the new upper control arm from Timeless Steel DeLorean. It's solidly made by SPC, easy to rebuilt. It has all the adjustment you'll ever need. It looks great to boot!