HEMIWagon Project Log: Update! Bigass Brake Kit Is Installed

Ride height needs serious adjusting. Needs more low in the front.

It has been a long time since this has been updated. A very, very long time. About 9 months ago, I alluded to this happening, and it has finally, after absolutely forever, come to fruition. There will be a lot of photos in this post, I will try to limit them as possible.

The car has sat, as I have dealt with numerous unforeseen issues, primarily unrelated to the brake swap, but some related. Let’s start from the beginning.


The LX factory brakes on the RT cars leave a bit to be desired. If you’re on the brakes for a while, it’s really annoying, as fade is common. Most people swap on the SRT brakes, but those come with an SRT price tag. Some of that is unavoidable, but there’s a lot of room for improvement. My main issue was that unless I get the early 4 piston front, kind of small SRT calipers, I would be forced into running 20 inch wheels all the time. New Jersey is not known for nice roads, as I’m pretty sure the state motto is going to be changed to ‘The Pothole State’ in coming years. I do not want to be running a low profile tire all the time. My second issue is that I want these to look great. The 4 pot SRT calipers just don’t really check that box for me.

Factory Hellcat front Brake caliper and rotor

Enter a lot of Googling. Day after day, until I find a 10+ page thread on LXForums.com about swapping on 8 piston AMG brakes found on early E63 AMG (~2007) or S55 AMG models of similar model years. This is a huge brake caliper. It’s larger than my size 10.5 shoe. I’m going to be putting it on my station wagon. This is nuts.

I found a full set up the calipers, front and rear, take offs from an S55 AMG (unknown VIN). This later proved to be a little pointless, as the rear AMG calipers are different from the rear SRT brakes and it’s not compatible. If only I knew (the first of many). About 4 days after purchasing the set on Ebay, my UPS driver delivered a large and kind of heavy box. After reading more on LXForums, I then went to RockAuto and bought front rotors for a 2016+ Charger Pursuit and rear rotors for an SRT Challenger (I don’t believe this would have mattered, the rear brakes on the SRT cars hasn’t changed since the early SRT cars AFAIK).

These were far from pretty when I received them. Very far.

More boxes arrived.

I deviated from the brake upgrade to replace ball joints and lower control arms and stabilizer arms as the years have taken their toll. This car has 210,000 miles on it, it is time to replace some of these parts. I was thankfully able to move my existing poly bushings over to the new arms. This process sucked, but it was successful. Adjustable lower ball joints were installed to hopefully help with any alignment issues that I hopefully don’t run into.


Back to the brakes. I inspected the calipers a little, but apparently it wasn’t enough. When I was disassembling the calipers hoping to prep for powder coat, I found a rather poorly installed helicoil and an absolutely trashed fitting. Great. I dropped the calipers off at a machine shop, and things got pretty bad. Machine shop had the caliper for 4 months for machining out 2 fitting holes. After a couple frustrating visits, I supplied a multi-pack of various fitting sizes for 3/16th line. Finally, with a couple of new fittings sized and tapped for install, and a total of 4 months later, the brakes were back in hand.

I have never seen an M10x1 helicoil. For reference, this is definitely not an M10x1 helicoil.

I played telephone tag with my powder coater, who I was able to drop the calipers off with about a month after receiving them from the machine shop, and the waiting game happened again. The color of choice? Prismatic Colors Illusion Copper. I had originally wanted Baer’s Arizona Copper, but when I saw the sample of Illusion Copper, I just went for it. About 3 weeks later, I got the call that the calipers were ready for pickup. Yes. Finally. I can install them. Maybe.

Damn. I own these. They’re on MY car.

Maybe indeed. I was specifically warned not to get brake fluid on the calipers, as it will dull the clear coat. Good to know. Well, I had bent some crossover lines, but they didn’t really work, and honestly they didnt look great either. Back to the drawing board on that. I go to put the lines on the calipers, and they didn’t get tight. Fittings were tight, line had a lot of movement. Shit. Here we go. Weird problems need weird solutions, right? I’m not going to be let down at this point. I’ve come too far. I started comparing the fittings, and grabbed a couple garbage fittings and cut a few mm of the end off. Discussed with the landlord, as he worked in a restoration shop for many years, and he was unsure. Maybe it will work? He humored me and helped flare the lines, but honestly wasn’t sure. Ghetto is the word that comes to mind as to how to describe this solution. I went to test fit the lines and guess what, it worked. Ghetto or not, I’m able to progress.


Of course, disassembly first. I had to get a lot of parts to get this far. The list:

  • Mercedes 8 Piston AMG front Brembo calipers
  • SRT 4 Piston rear Brembo calipers (from an early Jeep SRT)
  • Rear spindles from a Challenger SRT
  • Front lower ball joints
  • Front stabilizer arm

The rear suspension was a nightmare for disassembly. I’m glad I did it first, because lordy, the fronts at least seemed a lot easier in comparison. The driver’s side axle has a leak in the boot and the ABS tone ring is missing a chunk. Neither of these are easily accessible in the spindle, so I’m not sure what caused it, but it’s made a mess along with other issues to deal with. The passenger side rear was no better. The axle seemed to almost be fused to the hub. Lots of heat, and lots of beating with a hammer were the only way I made it through that. Despite mushrooming the outer thread of the passenger axle, I was able to save it by filing down the out thread at a 45 degree angle so the axle nut would go onto good threads and secure the axle properly. The axle boot and tone ring are replaceable, but not a fun job, I am going to try and have the alignment shop deal with this.


The front brakes provided a whole different set of problems. First, the stainless flex lines I had for the factory brakes proved useless. Unfortunate, but the angle and the banjo bolt were just not going to work. I ordered a set of E63 AMG front stainless lines, and encountered a whole new set of problems. The car has lines from the brake system that have inverted flares. The lines that Mercedes used for these giant calipers? Bubble flare. This required a lot of thinking in the back of an Autozone.


If you’ve never been in the back of an Autozone, let me tell you, it’s a magical place. There’s things the employees really don’t know anything about (no offense). I found a special rack with pre-made brake line, fittings and tons of other things that were more or less, exactly what I needed. I ended up purchasing a premade line with bubble flares, and another premade line with inverted flares. I also got myself a pair of inverted flare unions (couplers) that would be able to solve this stupid flare problem. After stopping by a friend’s shop, we had two adapters. Perfect. At least that wasn’t awful.

Yes, it’s blurry. But I came up with a great solution that works really well.

Some annoying tinkering later, and it was assembled. Easy, right? Far from it. I was able to bleed the rear brakes and got some fluid to the calipers, but had issues with the front. Don’t get brake fluid on the calipers, right? Want to play a game? It was bad. A loose line, and then bad fittings. I went through an entire roll of shop towels fighting with the driver’s side front caliper. Somehow after tightening the passenger side front, all was well over there. I now have two bleeder repair kits in the driver side caliper. TWO. Somehow, despite my complete lack of faith, they both hold.

These are actually awful. I hated the installation.

I took the car out to try and bed the brakes. Needs to be bled still, but more progress has been made in the past two weeks than the past 7 months in getting this working. I’ve stared at the car, unable to drive it for months because I wanted to do this right, modifying a little here and a little there, fixing broken things, even going as far as completely disassembling the interior to do a full detail on everything in anticipation of being able to drive this car again. The list of additional parts I needed to figure out:

  • Stoptech stainless flex lines for Mercedes calipers
  • Inverted to bubble flare adapters
  • New axle nut
  • Motul DOT5.1 brake fluid
  • EBC Red Stuff brake pads front/rear
  • 2 Bleeder repair kits
  • Axle boot
  • Axle ABS tone ring

And I’m sure I forget plenty of details from this swap. Would I do it again? Hard to say. I haven’t yet felt the full braking force, but I have gotten a taste of it. It’s intense. These AMG calipers have close to twice the pad surface area compared to factory SRT brakes. Can’t find much compared to the factory RT brakes, but it’s certainly a lot different. These brakes will certainly compliment the planned engine swap. I’ll be saving up a lot of pennies to make that happen.

Damn. This thing is mine. It’s really actually mine.

What else has happened to it besides the brake upgrade? Two pretty big things. First, I was finally able to score an amazing deal on SRT valve covers and coil packs. My aging coil packs were in really sorry shape. One night I saw them arcing, and that was the biggest reason for not driving the car for so long. Last thing I need is a fire. I was browsing the local Facebook Marketplace ads, and I saw a 6.1L intake and exhaust manifolds for sale, with a coil pack visible in the background. These things are expensive, so I shot the seller a message, thinking maybe they’re still available, maybe I have a shot. After some back and forth, he said the valve covers were not available, but I could have the coil packs for a great price. I rush out to meet him, and he decided to give me the valve covers as well as the coil packs. I learn it’s from a core return motor that’s going back, and while he was originally going to send the valve covers back, he’d do me a solid and give me everything, as he had no use for it. He was repairing a Cherokee SRT8 had spun a rod bearing, and got a replacement complete motor for that car. I bought the coil pack adapter wires off the internet, and ended up taking all of them apart to solder connections after finding a bad adapter. But here I am, running new valve covers and coil packs that aren’t on their last legs.

Original factory coil pack to the car. 210,000 miles on it. Pretty sure that’s not how it’s supposed to look.
This is a lot cleaner than when I first bought the car.

What else did I get? A set of 20 inch wheels. After going through a ton of trouble to make sure I would be able to run my 18 inch steel wheels with this brake kit, I ended up with a set of Factory Reproduction SRT10 replica wheels in 20x9 and 20x10 front and rear respectively. They need to be repaired, every wheel has curb rash, and the rears have a couple slight bends, but they were at a salvage yard for cheap enough that I couldn’t help myself. I’ll have a good set of aggressive tires put on them, and they’ll be a set of track wheels for the car when all is said and done. Admittedly, the steelies are heavy, and they have a really big sidewall, which wont help the car corner better. In the name of performance, I can handle a set of 20s for occasional use, but I do really love the look of the steelies.

These make the brakes look really small. It’s weird.

Hopefully the next update is sooner, the car is running well and going on adventures again. Even only driving the car about 15 miles today was a huge success and felt amazing. It’s been a long time since I’ve had it out, and it’s never felt this great before. I’m relieved and excited that my vision for this car is continuing to take shape, and looks damn good doing it.

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