Project C63 has been a pleasure so far – right after I put on my new HRE FF15’s and Toyo Proxes T1R, I had to get some suspension for the vehicle.

Without much time before the HRE Open house, I decided to put on some H&R Sport Springs W204 C63. So here is my review of the H&R Sport springs for the Mercedes C63 AMG:  Right away the drop was perfect, it wasn’t too low that it would be undrivable, but it covered up the wheel gap. The main reason I got the springs was for the look, and to take care of the nasty wheel gap caused by the 19” wheels and tires. I was actually pleasantly surprised with the ride having not changed to significantly. I would describe it as going slightly stiffer in the way the car rode from stock before (which is still sporty). Overall I would say the suspension felt almost the same, while lowering my center of gravity, and did what I wanted made the car look great complimenting the new wheels and tires.


Meanwhile, I didn’t just want the same feel; I wanted to enhance the already great suspension the C63 had. I remembered meeting with BC during 2014 SEMA and them showing off their new lineup of more advanced coil over offerings.

I was thoroughly impressed by BC’s offering, at the time I thought, “ok these are going up against the big boys, the Penske, Ohlins, AST, KW Competition Level, so this would be way out of any price range that would be affordable”. But man, I wanted one of these suspensions; I’ve had the privilege that very few people in this world have ever had. I have seen a ton of vehicles, a ton of different suspensions from Air Ride (Airrex which is on my Porsche 996TT), from KW, ST, Solowerks, CKS etc. on different vehicles. When I drove in some of the upper echelon of suspension an Ohlins on an E46 M3, and Penske’s in a Ford GT, the ol’ “butt Dyno” feel said it all, “this is what you REALLY get when you pay this much”. You get a suspension that is incredibly comfortable, responsive, and predictable.

Comfort is the reason that a driver will go harder and push the car further into a turn, predictability lets you know how the car will react, and the response/feedback you get is what allows you to correct yourself going further into perfection of that magical turn.


So while researching the new BC Coilovers line, turned out they made one upgraded coilover for the W204 chassis, and it was the BC ER Type (I wish they would release the ZR line now), Typically the BC coilovers are known for the BR Type the $1000 coilovers. To my amazement these weren’t selling in the $4000 – $12000 range as the other high end coil overs I mentioned. The BC Racing ER Series External Reservoir Coilovers for C63 AMG were just $1850! I was surprised to say the least. I had to get these on my car, this was in line with the other mid-tier coilovers but I was getting a far higher end system.  I put in my order, it took about 2-3 weeks to build because they aren’t just a normal on the shelf item, while looking at the tracking numbers, it looked like parts came from Taiwan but then went to Japan (was it inspected and assembled there?) and then came straight to me.

We got them installed, here at ModAuto (our shop), I had no idea how I wanted to get them setup in terms of adjustability. Dave, our tech, wanted to play tricks on me to see if I really could tell the difference from every click that we were adjusting, by either not adjusting or adjusting every time he was near my car, basically he wanted to know if it was the ‘Placebo effect’. Well I could feel the difference, it was noticeable each time, and it was really evident.  I have never had an external reservoir coilover before, and so whatever was going on here was really impressive. The ride quality went from super luxury comfort, to sporty feel and finally, I settled on a “sports” kind of feel. After getting the feel of the car right, we got the alignment done on our new Hunter Alignment machine (here at ModAuto) (which made a difference as I could instantly feel more grip created by the balance in the vehicle). So I was set.


So what is my take on the BC ER Type Coilovers for C63, as far the feel was concerned?

The car now eats up imperfections of the road like they don’t exist – the best example is going over a rail road crossing – and there’s one right outside our driveway at the shop, and so most times when I hit the rail road, the car will shake a bit, or have that little shimmy to it. Now, the car will go over the rail road crossing, and you still feel that you went over it in the steering wheel, but there is no movement or shake. The BC Racing External Reservoir shocks just ate it up like it was a smooth surface, not moving my steering wheel from my goal.

And of course there’s the all important Girlfriend test. Her opinion is that the car is even smoother, if she wants to take a nap, the car is more stable, so if anything, it’s even more comfortable. I set mine to a sport stiffness level – I just prefer it that way, but again, I can easily get to the coilovers, make a few clicks and adjust it to a softer ride very easily in about 5 minutes – unlike any other coil over.

Yes, I have to say an External Reservoir coilover’s worth it. While yes, the saying “you get what you pay for” generally holds true, dang, I have to say that I got a great value in these, as this is right up there competing with the best. BC has out done themselves; they are changing the landscape of the marketplace as they are able to offer an incredible price value for an amazing price point.


Project C63 AMG has really turned around since its plain look, the front lip and rear diffuser at ModBargains transformed the look. The HRE FF15 is gorgeous, and has turned heads everywhere I drive. I get a couple thumbs up a week, from fellow enthusiasts. I think the pictures speak for themselves. The wheels are also really light weight, so I can feel it in my turns which is a major plus, and so far all the pot holes and imperfections of the road have left these wheels flawless, great quality from HRE. Last but not least, I have to comment on the Toyo Proxes T1 Sport. I went with Toyo’s again, they impressed me with the T1R’s for the Porsche 996 Turbo Project, and this time I wanted that same great sports feel and longevity. So far the tires have really shown their grip, in both rain, and in the dry. They compound is not hard or harsh, meaning a lot less road noise (big factor for daily driving for me). Toyo continues to innovate and these tires are on part with the best I’ve driven, with the exception of great value. They’ve been the perfect daily driving tires I could have looked for.

Whats next? For the C63, maybe more power, but stay tuned?


That’s it for now, but by no means is that all – we have more W204 Parts & Upgrades in store coming soon.

Want more muscle out of your Mercedes, or a set of these BC Racing ER Series Coilovers for Mercedes Benz C63 AMG for yourself? Consult our team of Mod Expertsor ask Ron himself – to find out how we can tailor your Benz to your tastes. Give us a call at 714-582-3330, email us at or chat live on so that a Mod Expert can assist you with virtually any aftermarket upgrade for a Mercedes Benz you can imagine.

Story by Ron Hay
Edited by Nick Gregson
Photos Bryan Munoz