So during the course of my 8-9 months worth of investigating, I haven't really come across any definitive DIY resources for actually doing this conversion (other than if you're lucky enough to live in the UK and can afford the 1320 turbo kit). I figured it might not be a bad idea to put together a definitive list for others who may be researching this same route, as well as some of the pro's and con's?

Here's what I've found so far that needs to be done/converted to even make this work:

Water Pump: options are either swap over to the standard r50 pump or run a Craig Davies EWP. I think I prefer the r50 pump in this option, including the water neck to attach to the block in the alternate location while the supercharger driven water pump location will get a block off plate.

Tensioner: r50 tensioner will replace the r53 model in this case.

Alternator: I'm still working this one, I have a feeling I will be making an adapter plate to mount the r53 alternator where it would normally be on the r50 model and replacing the alternator pulley with one from a r50 as well. From my research it looks like the r50 alternator has a 2 pin connector, whereas the r53 is a 3 pin.

*Update: The oem r53 alternator can be used, however you will have to change the pulley to a r50 pulley and re-use the nut from the r53 pulley. The shaft sizes are the same, but the threads aren't. Also, you will have to shave 1-2mm off the face of the alternator to make the r50 pulley seat all the way. You can do this with a grinder if you pay attention and don't nick the shaft. The alternator will be flipped upside down and mounted where the supercharger was previously. Now you will have two bolts on the bottom of the alternator, and 1 on the top. The top bolt will require a spacer shim as well that is almost 7/16" in thickness to take up the gap (you will see it when you go to bolt up the alternator). The r50 water pump will then mount below in the alternator's old location. I highly recommend running a tap through the bolt holes, as they've probably rusted up a little.

From what I can see the belt routing will be exactly like for the r50 at this point, which should mean removing the r53 idler pulley from the block as well.

Since more than likely your a/c will have to be removed if you want to run a custom front mount, you will end up running a custom belt size (VW belts have been used quite often) or have to use an A/C delete pulley.

Other pieces to be removed/replaced/moved:

All the plastics under the cowl will need to be removed to give more room for the turbo, and the overflow tank and power steering tank will need to be relocated out of the way. Obviously any intake or air box will be removed to be replaced.

Top mount: Unless you plan on going twin charge, this will get removed as well.

Supercharger: completely removed unless twin charging.

Bypass valve: completely removed unless twin charging. For a turbo setup this will be replaced by a blow off valve, either built into the turbo (depending on turbo selection) or externally mounted to the charge pipes as close to the throttle body as possible to cut down on plate reversion back to the turbo when the throttle body closes.

Throttle body: unless twin charging, it seems the only two options I've come across so far is A. welding an aluminum plate to the intake manifold and having it tapped/threaded for bolts or studs to bolt the throttle body to it, or B. have an adapter plate made to go from the manifold's 3 bolt pattern to the throttle body's 4 bolt pattern. I will be trying the adapter plate method first to see how it goes (just in case I ever do want to put the car back to stock). I'll update further as I see how the adapter plate works out.

Exhaust manifold: Obviously this needs to be replaced completely. So far I've only seen one bolt-on option out there, and that was for a very pricey Kav's manifold. Don't get me wrong, it's a great looking manifold, but for a car that really isn't worth much I'd like to avoid dumping too much money into it.

That being said, I found another option via a friend who has made a couple of these for some guys across the pond: a stainless steel adapter plate. It consists of a block of 1/2" stainless that is machined for the Mini Tritec flange on one side, and then adapted to a Honda D16 pattern flipped upside down on the other side. There is a particularly fast Greek turbo swapped r53 that uses this same adapter plate, and it works great. The best part is that you can find cast iron or tubular D16 manifolds everywhere, and the price is much better. T25 flange, T3 flange, DSM flange, you name it you can find it with a Honda manifold. Or a third option for the really DIY guys who like options: buy a Honda D16 tubular manifold and cut the flange off, take your stock exhaust manifold and cut the flange off that, and then have the Honda manifold welded to the Mini flange.

Turbo selection: this really depends on your personal goals and power range, as well as street driveability range. The most common choices seem to be Garrett GT2860rs or GT2871r turbos. The 2860 has more street-ability, whereas the 2871 seems to be pretty laggy when viewing the flow charts. Standard T3 frame sizes are also options for those who are more budget minded or looking for a more balanced mid-range power band, such as standard T3 50 or 60 trim turbos (Garret or Turbonetics usually) which usually run the smaller .48 a/r housing for quick spool response and can be had as either a ball bearing or journal bearing design. I will be running the T03 50 Trim with a .48 a/r exhaust housing which *should* (on paper anyway) give me 10psi by 2600 rpm and 18psi by 3400 rpm for a great mid range power band, and still provide 27 lb/min of flow with a lowest efficiency rating of 65% at the top end of my rpm redline. While it's not a big power monster turbo, it will give me great streetability that flows better and is more efficient than the Eaton m45 and would equal or slightly beat the output from a TVS R900 supercharger without the parasitic drive loss inherent in supercharger designs.

More options using a D16 manifold now become available outside of the T25 based flange design, such as MHI's 14b or 16g turbos, or even T3/T4 based turbo designs. Learning to read the compressor flow charts is a good indication of understanding how much lag you can expect to see, and how much overall flow a turbo is capable of for the engine's requirements.

Wastegate: there are two types; internal or external. External usually controls boost better than an internal system, especially at higher boost pressures, but if space is a limiting factor an internal gated design will work just fine. Be aware that internal gates are prone to suffering from boost spikes if running higher boost levels.

Oil feed and return lines: you'll need to feel oil to the turbo, and depending on the turbo you will probably need a restrictor to limit oil pressure going in so as not to blow the turbo oil seal. Pressure limits vary by turbo, and ball bearing designs usually require a lower pressure than the older journal variants.

The return line should dump into the pan, although where is an argument as of late. My rule of thumb was always tap into the oil pan as high as possible in a gravity return system, and always use a return line at least double the size of the oil feed line.

Downpipe: this is going to have to be a completely custom job. There are no pre-made bolt on parts for this, and every setup I have seen so far (other than the 1320 kit) has been different.

Intercooler/charge piping: Again, this is going to end up being completely custom, and you will end up losing your air conditioning in the process. *Edit* I'm working on a new front mount design similar to the Be-Kool front mount design for the stock M45 where I would use a 27"x5.5"x2.5" bar and plate small front mount that sits right above the radiator/AC condenser, and will probably use the radiator from a Golf GTI or similar. A 2 or 3 core radiator will sit low enough that the intercooler *should* have enough room to sit right above and clear the hood, while still allowing airflow in through the upper grille. You should be able to keep A/C this way.

Radiator: some opt to leave the stock radiator with r50 hoses I'm assuming, I will be going a different route using a 3 core Honda Civic aluminum radiator. Height is still the same as the factory r53 radiator, but it sits half as wide to allow room for piping/hoses/etc. If you live in hot climates, this might not be the best option for you, I'm doing this for space limitation reasons on my own build with custom coolant hoses.

Injectors: factory injectors won't be up to the task, even if you have upgraded JCW 380cc injectors. Rule of thumb for injector sizes is picking injectors based on your power goals and limiting them to an 85% duty cycle at the most as a buffer. I'm shooting for 250hp for now, and looking at a set of 550cc injectors to make sure I'm safe and won't run over 85% IDC. Bigger injectors are required for E-85 usage at lower power levels, and rough rule of thumb was always double the size for running E-85. Another limiting factor will eventually be the non-return style fuel system. For higher power goals, a return style system will need to be constructed. I won't touch fuel pressure regulators or any of that for now, that should be another topic of discussion. Another thing to keep in mind is that Mini runs a higher fuel pressure than most standard injectors are tested and flowed at (usually 43.5psi, R53's run closer to 51.45psi last I looked), so in essence a smaller injector will appear to be larger simply due to the higher rail pressure. With that in mind, in most turbo applications the fuel pressure regulator also acts like a 1:1 rising rate regulator, increasing fuel pressure to increase fuel as manifold pressure increases. I do not know if there is a maximum level where R53 regulators top out at, or if there's a level where the pump may not be capable of keeping up with the demand. If we assume it's a 1:1 rising rate, fuel pressure could increase to almost 70psi before hitting the end of the TMAP sensor.

Wideband o2 sensor: this is pretty much a no-brainer on any boosted car, and comes in very handy when tuning and logging, or just to keep a general eye on how your car is running. If you don't have one, do yourself a favor and get one.

ECU/DME: There is no real cheap solution to this. After talking to various turbo r53 owners, the general assessment is that the factory DME sucks pretty much all the way around. I tried emailing the engineers at Bytetronik to get a little more insight behind their tuning solution, but as was expected I got no response and a bit of a rude response from them on here. Regardless, the factory map sensor(s) are limited in range and apparently don't like seeing anything more than 17-18psi of pressure above atmospheric, at which point they implement a fuel cut which is dangerous to the motor. In the past people have used FA53 and a map clamp (such as a fuel cut defender) to avoid fuel cut at higher boost levels, but most users have said they have some type of abnormal issues even when just cruising around outside of boost range. I don't know if this is just user error, as no one can actually provide any real information other than "it sucks to use", and most have never had any tuning experience before.

I might not rule out the FA53 route just yet, most depends on whether or not the base VE table can be modified (which controls closed loop fuel/timing), and since a turbo conversion does change the effective VE (Volumetric Efficiency) of the motor it will need to be adjusted accordingly to bring short term and long term fuel trims back in line. Once they are in line, then boost tuning can begin to ensure safe and consistent results. If this ends up working, this may be a more desirable option for the more hand's on guys. I'm still waiting on information back before I take the plunge into a system that may or may not work, but I'll keep updating this to let people know.

*Update: I decided to not even bother with the FA53 route after finding out from a few others that many of the options that would make life a lot easier with tuning a turbo conversion are locked for the end user. There are some in Cypress who are making good strides tuning stock ecu's the old fashioned way (KESS/Galetto/MPPS and WinOLS) for turbo conversions, but I decided it wasn't worth the aggravation. I decided to go the stand alone route and call it a day, at least this way I can also remove some redundant sensors since where I live doesn't have OBD2 testing with their emissions.



All in all this is not a simple weekend bolt-on ordeal. For those with fabrication and welding skills it can be done, but will still probably run at least $5-6,000 (unless you already have most of the parts laying around). After seeing this, it makes the 1320 kit look like a pretty darn good deal, but for those of us who like to build and fabricate, it's a heck of a challenge!

Feel free if anyone has anything more to add to this that I may have forgotten or overlooked, the more information the better! Also, I don't want this to become a fight over why we should just stick to the factory design of a supercharger, everybody's goals and builds are different with different purposes, so please keep things civil and constructive!

 

the power worth giving up the throttle response? R53 so much more fun than my r56 and 135i due to the turbo lag, and in autocross? Lag is a killer

 

That's an argument I've heard over and over again, and to be honest is an argument by the uninformed who've never actually done their research or testing of appropriately sized systems.

A well balanced turbo choice would have very minimal lag, coming into its powerband around 2500-2800rpm and running all the way to redline. Your r56 actually makes more torque and power down low compared to the r53 but due to direct injection also falls off flat in the top end. For autocross usage you would not be selecting a turbo that doesn't reach it's powerband until after 4,000rpm (again, 2800-3000rpm range is optimal), and if you autocross with your rpm's below this range then you are pretty well clueless about how the Eaton m45 works as well, and probably run a very slow time. Comparing supercharged race cars to turbocharged race cars, how many supercharged versions are there compared to turbo'd ones? Not very many, and for good reason.

 

you ignored what I said

I autocross (and win, won last weekend) 3 cars, r56s, 135i, and R53, the throttle response mid corner is drastically different on/off throttle. On my turbo cars I have to increase throttle going into the corner so it'll get on boost on the exit

on the r53 I don't get on the gas nearly as soon as there is no delay it's instant

On the street, no real lag to deal with, but mid corner in an autocross there is a huge difference

all these are stock, you cannot change turbos in autocross unless you want to race gutted civics that are going to destroy you

you talk like you do not race

 

I don't race anymore, I did race VSCCA & SVRA for a while when I built Lotus/Lola/Porsche/Ferrari race cars in the late 90's. All of our forced induction platform cars were all turbo, and all highly modified way beyond what the average Mini owner does.

Again, you didn't pay attention to my statement of "choosing a correctly sized turbo" that is based on your engine's flow requirements, based upon rpm range. You can easily look at a compressor map and see whether or not your engine will still be in the response curve of a compressor (which by the way will probably have a 70% plus efficiency rating as compared to a measly 55-60% out of that wheezing Eaton hairdryer) at a certain rpm range to make sure you have an instantaneous response.

Take a look at an Eaton M45 map, and then take a look at a MHI td05H/14b map and see which one will outperform the other (and the 14b is a very small, extremely responsive turbo that still outputs more cfm than the eaton).

To which degree comes the question: where in any of my post did you even assume that I was suggesting this as a good viable alternative for those who run solo or scca or even hdpe in stock classes? You assumed, and at this point are just looking for an argument. If that's the case, take it to a side thread and you can argue all you want there, just don't do it here unless you have physical cold hard proof your M45 will outperform any number of turbo compressors I counter with (which you can't, because even the TVS 900 doesn't have too great of a flow rate with only a slightly better efficiency range over the standard M45).

 

I was as specific as I could be, supercharged engines have better throttle response see post #2

maybe you could run 2 turbos and keep one wastegate closed like bmw does on the 135i but I don't see how that's gonna work on a mini your going to turn an r53 into an r56

 

None of what you have mentioned in any of your posts has any real relevance to the main topic, which you apparently didn't read because:

The r56 has a different power curve simply due to it's injection system and extremely small turbo. Direct injection has limitations that affect the power band, such as good fuel atomization at higher rpm. Also, a single turbo is always going to have the wastegate fully closed until it hits it's operating pressure.

 

So about that throttle response I think this is why twin charging is a thing

 

I've never had any issue with throttle response on any of my turbo cars, especially not when the rpm's are up higher such as rev matched downshifting heading into and through the corners. If you let the rpm's drop drastically then it can have some lag to it, but heading properly through the corner (especially with a tuned suspension) you can adjust to maintain throttle response.

Currently (and previously) I have my suspension set where I have to keep on the throttle steady through a corner (hard braking entering, feather on apex, hard throttle out) which keeps me continuously at that power band. If I don't keep on the throttle some through the corner, the rear likes to turn a little too far at times. In my old Evo this phenomenon was extremely fun as you could slide the rear around the corners while full on the throttle and letting the front tires pull you through the corner.

 

all my turbo cars have throttle response issues, I'm not talking about below 4500 rpm, the on/off throttle response is nothing like a supercharged engine.

My minis are both setup to get real loose in the back if you lift in the wrong spot, I have spun out on an autocross course

 

Sounds like pretty poor tuning then. Increasing timing coming back on the throttle can help take up some of the slack. Obviously it will drop off as pressure increases, but it should be a smooth linear power band as much as possible.

On my 2.0 liter Evo I ran a 69mm wheel compressor, one I was "told" was too big and would have a lot of lag time and throttle lag getting back into it. It actually had neither, spool time was a slight bit longer than factory (3100rpm instead of 2800), but off and on transitions (such as gear changes or letting off the throttle) was nearly instant. A 4" downpipe, along with a good manifold design helped tremendously, as did my tuning. It's all about combining the right pieces to optimize the design.

 

bone stock bmw & mini tuning, the 135i has very little "turbo lag" but that is not the same thing as throttle response

 

You're also talking about electronic throttle bodies where each one is calibrated differently. Factory r53's with the standard "S" mapping wouldn't allow the throttle plate to open completely, whereas a "JCW" map would. These aren't cable operated throttle bodies anymore, and if you want to control throttle response better you might as well convert to a stand alone system to have complete control over it. Otherwise, throttle plate angle is controlled by torque mapping according to power levels the DME "thinks" it should see, regardless of your throttle pedal input. It works the same way when the car enters a "limp mode" status...rpm is limited to a certain range, as is throttle plate angle.

Again, another reason why a stand alone system would be better to control a turbo conversion on a r53 (and to try and put us back on topic here).

 

I have a factory Jcw and a regular r53 I autocross both and both have stock tune throttle response is the same as far as I can tell

 

It's not, I've actually seen the mapping for the two r53's in WinOLS. The JCW map definitely has a better throttle response curve and allows it to fully open the plate; the standard "S" map only allows up to a certain percentage. When I flashed my r53 to the JCW map I lost most of the throttle hesitation that was present on the standard "S" mapping. As part of my conversion with a stand alone I'm looking into swapping to a cable controlled throttle just so I don't have to deal with that anymore.

 

it feels the same to me, identical basically

my 2005 does not have that awful pig rich stink when I get on it, I kinda want the regular tune on my JCW

 

There isn't much of a difference performance-wise between the standard S and the JCW. Slightly more cfm flow through the motor, but they fatten the fuel curve to keep it safe. I have the 210hp JCW map with the 380cc injectors it's mapped for, the only time I have the pig rich problem is when first starting the car (where cold start is controlled by the IAT & water temp sensor scaling), but I'm also pushing the charger further than the JCW. Having a tune done on your JCW will help, but it can also be pandora's box with the Siemens ecu's.

 

On my JCW any time I go over 4500 rpm you can smell the rich + catalytic converter wonderful smell

JCW head flows 11 % better on a flow bench, the pulley is 11.something smaller too and the airbox does flow a good bit better they did a good job matching it all up

You can tell the jcw pulls harder all over, but it's not a shocking difference like throwing a tune on a N54

 

I don't have any of those issues currently. I have a standard "S" head that I smoothed the intake ports heading into the bowls while leaving it rough enough for atomization purposes, and port matched the exhaust side to help it breathe a little better and open it up more than a JCW head. That mixed with a knock-off header, DDM works style intake, 17% reduction pulley, and 380cc injectors and the 210hp map help it move along decently. For me it's not enough though, this is literally the slowest car I've owned in over 10 years. I can't even say it's the best handling, because I had an '89 Civic Si hatchback that out handled it all day long with suspension mods.

 

Let's be honest too, this forum isn't even really alive anymore, so my guess is you're one of the remaining few who is pretty bored with what little content is left here lol.

I really need to spend more time on the boards across the pond.

 

lots of look at my picture threads here now :(

 

Most of the MINI community in general doesn't seem all that interested in diy work or making more power or even dialing in better handling. I don't know why I bothered to start this really, guess I was hoping there were more r53 guys interested in sharing info on their successes or failures to create a guide for others. Even the old build threads from years ago don't have working photos anymore, and every day on social media the only things I see about MINI's is "how low can I slam it" or "can I fit these ridiculous offset wheels". It makes me sad. :(

 

I've built a few turbo R53's. Hit me up over on Instagram for pix @ regalmetalworks

 

Thanks Trickle X! I just followed you on IG, I'll shoot you a message there when I get a break, looks like you're only a few hours away from me too. I believe I remember seeing your first build back on HomeMadeTurbo a while ago, I go by the same name on that forum but haven't been on there in quite some time. I was one of the (un)lucky few beginner OG members when the site first started haha!

Can you confirm at all the alternator fitment? That seems to be the biggest question I'm trying to clear up; some say run the r53 style on an adapter plate with the r50 pulley due to the connector plugs, and others in the UK are able to run the r50 alternator and have it plug in and work properly.

I saw one of your latest r53 builds on IG too where you used the civic half-rad, I'm thinking that's the way I'm going to set mine up too due to space limitations. The only downside is finding a front mount to fit the space and cool the charge down. I'm a little limited not having access to a tig to weld aluminum, so custom end tanks would be a "send out for fabrication" job.

 

Thanks for the follow! I ran the R53 alternator and changed out the pulley with the r50. It may be running a little slow as I run about 13.8v when charging. I also am running the r50 belt tensioner and r50 water pump and that is it. If I remember correctly I am using a 33.5" accessory belt, which is used on a vw tdi engine. If anything the r50 water pump barely keeps up. I have to run my fans when it is hot out or risk overheating when sitting in traffic. It is a down and dirty way to get it up and running, but I am sure there are far better ways of running it.