I wanted to introduce my new project and get some community feedback on the direction we’re heading. I watched this late-production 2006 R53 sit on FB Marketplace for over a month. Realizing its neglected condition, and the fact that it’s an automatic, it was highly likely destined for the scrap yard if someone didn't step in.

This is going to be a father-son build. While we aren't strangers to diving deep into European car rebuilds and restorations, this is our first venture into the R53 chassis. Our plan is to completely bring it back to life and build a fun street car that will see the occasional track day for some spirited fun.

Now, I already know what most of you are thinking, and I completely agree: a manual R53 is a way more engaging, grounded driver's car. However, I’m genuinely happy to save this one from the crusher and give it another lease on life. Plus, there was a practical family upside to the automatic: my son was having some serious reservations about learning to drive a manual on a car we plan to rebuild from the ground up. He would not be happy with himself if he burned up a fresh clutch after putting this much collective sweat equity into the garage.

We are currently in the deep research phase and getting ready to place our first major parts orders. Since the front end will be in Service Mode and the cylinder head is coming off for a refresh, we are planning a heavy mix of preventative maintenance, oil leak fixes, and Stage 2 supporting mods all at once.

Here is our blueprint for the build so far:

Engine, Cylinder Head & Seals

Head Gasket

ARP Cylinder Head Stud Kit

Timing Cover Gasket & Front Shaft Seal

Crankshaft Position Sensor O-Ring & Oil Pressure Switch

ARP Cam Sprocket Bolt Kit

Supercharger & Cooling System

17% Supercharger Reduction Pulley

Alta Performance Serpentine Belt Tensioner Stop

Full Supercharger Oil Service (Including brand-new water pump)

New Silicone Intercooler Boots

Full Coolant Hose Set

Fueling & Tuning

380cc Fuel Injectors
Remote Tune, Most likely go with AdrianclBrakes & Chassis

New Rear Rotor, Caliper, and Pad Set (Rear calipers are getting completely refreshed)

• Note on Front Brakes: Keeping them stock for now, may upgrade tot the R56 bigger brakes.
  

What Am I Missing?

We want to do this once and do it right while the front clip is off the car. For the veteran R53 owners out there: does this look like the right path for a reliable, aggressive street build? Are there any hidden "while you're in there" items, gaskets, or quirks specific to the late-2006 automatic platform that we should add to our checklist before we start clicking buy?

Looking forward to sharing the progress as we tear into it!

 

Thanks for your rescuing this 1st Gen R53.
It sounds like you know your way around an engine and going after oil leaks as well.
I would imagine a seemingly neglected R53 would be in need of a subframe refresh as well (Although FL isn't too bad on cars) - Personally, first and foremost *Suspension and handling wise: Front lower control arm bushings - I would replace with Polyurethane (e.g:Powerflex is a popular choice). The same is reccomended for sway bar bushings, lower engine mount as well as upgrading to a stiffer upper engine mount - But you may wish to consider how much vibration is acceptible/tolerable to you as a daily driver.
There is much discussion regarding shocks/struts vs coil overs - I have had both (currently on Bilstein 14 coilovers) but really don't have much to advise or recommend.
As far as ball joints, drop links and such; I would try to stay with OEM where budget allows. There is a lot of aftermarket crap out there.

 

Don’t waste your time on an automatic transmission (CVT) , because it will cause you more trouble than you realize…

 

I agree but I'm pretty sure only the R50 has a CVT . The R53 has a six speed Aisin torque converter style automatic gearbox. If I'm not mistaken.

To add to this thread; refresh all balljoints, bushes, o-rings and the power steering lines.

Personally I would not take the head off if there is nothing to fix or upgrade

 

[QUOTE=LukasH;4712816]I agree but I'm pretty sure only the R50 has a CVT . The R53 has a six speed Aisin torque converter style automatic gearbox. If I'm not mistaken.


Thought you had the basic R50 CVT ; the R53 “S” 2005 & 2006 came with the Aisin 6-speed automatic . I found an epic thread on NAM about all the same issues these automatics are having. 6 pages deep so far and I have come to believe that the Aisin 6 speed that's in every automatic Mini Cooper S since 2005 has design defects.
Mini contends the fluid should not be changed until 100k, but that's false. Even my 2006 MCS at 40k the fluid is burned up and used up, allowing for many of these failures. This same tranny is in various VW/Audi models, however modifications have been made to theirs for greater cooling and thus, longer life.
Tough call here: Do you spend the $ (about 6k on average) to rebuild a known defective trans understanding that more frequent fluid changes are required moving forward... or do you get rid of it?

 

05 MCS r53 - auto is used in Volkswagen too Asin Warner AW * something. It’s an ok unit. I have a Feb 05 car. I had trans rebuilt at 177k - Feb 2025 - good unit. I added an external oil cooler - bypassed the beer can thing. It’s a solid car.

I’ll add a bit. Mine has a Dinan airbox with a UUC exhaust - that opened stuff up - that was done in 2009?

2021 added a Dinan pulley.

i am running stock injectors. You can look around, and ask, but mine has been like that since 2021 / 151k, and a driver with a lead foot ( not me ).

non OE replacement parts have been of lower quality recently- shop carefully.

the trans rebuild was $$ (5600 ?) but it does drive like new. The external cooler took a lot of thermal load away. This will sit in traffic all day and be good.

link to my thread on cooler

https://www.northamericanmotoring.com/forums/r50-r53-hatch-talk-2002-2006/370900-mini-r53-six-speed-automatic-external-cooler-mod.html

 

As @Here2Go said, all those powertrain mods are fine but since you are planning track time, ensuring the suspension is in really good shape is perhaps more important than power. Even in street driving, it just makes the drive so much better. Also all of the motor mounts are likely worn/broken, so probably add a set to the list.

WRT the powertrain mods, if you are pulling the head and planning a tune (tune is strongly suggested), you may as well put a performance camshaft in. With the smaller supercharger pulley, you should install 1-step colder spark plugs and since the harmonic balancers are known problems, consider an ATI Super damper to banish those problems. You didn't mention oil pan gasket, so I'm not sure if you are planning to get that while you're going this deep, but if you are, you might consider a baffled pick-up tube or an oil pan with a baffle built in. This will help keep oil "trapped" around the pick-up tube during hard cornering. Maybe replace the PCV valve, thermostat, timing chain and/or tensioner, gears and guides.

Don't forget the ARP lube for your ARP hardware.

 

Alta Performance Serpentine Belt Tensioner Stop

^^^that is a scam for new guys, in my opinion^^^

first of all, it's easy for me to spend your money. it's up to you to decide what you need to do and what you can skip.

i'm still relatively new to the r53, but i have learned that things seem best done by system. example: you're doing some engine work. you're going to be well served to do everything related to the engine at once. i'd reseal the entire engine if starting from scratch. and, personally, i advocate responsible and metered use of RTV on top of the oring gaskets for the timing cover and oil pan.

timing chain set
supercharger service
thermostat
water pump (make that call when you can visually inspect it)

then, when you get to suspension & steering, you could do all at once...
drop subframe
ball joints
inner & outer tie rods
all bushings
*struts and strut mounts could be done later easily enough
while subframe is out, power steering hoses to reservoir is super easy to do at that point

brakes
research the r56 conversion, at least for the front
i've found that a nice set of hawk pads + decent budget friendly rotors is pretty good. maybe upgrade brakes later if your current ones don't need new calipers & hoses.

fuel filter