Assuming you haven't drastically changed anything and just swap from supercharger to turbocharger the volume of air won't change. The intake temps could change which will effect density. The one big change is if you changed the intercooler. Most won't stay with the stock unit. That could have a large effect.

People are probably making lots of changes at the same and hence the tuning issues. I still think that a simple turbo kit using a similar to stock intercooler won't change the fueling needs out of the range the ECU can deal with.

 

Don't forget if you did swap out the supercharger you would be freeing up horsepower because it takes horsepower to turn that blower assuming you make the same amount of boost between the two. The top mount is terrible which is why I bought an a2w even though we have scoops there is insufficient air flow over it until you are doing about 40 mph which is why we have things like ram air scoops to try and force more air over it.

 

You know your both wrong.
Just because it takes horsepower to turn the blower don't think putting a turbo on it will just be instantly more efficient. you have to take into account all the plumbing it runs through in order to get the air into the motor. Inefficient plumbing.
not exactly the ideal solution.
And yes
The volume of air will change drastically from what the supercharger will put out.
In order to make more power with a turbo you will need to stuff more air in, Be it through more boost or from a large turbo at smaller boost.
Another thing to consider is the turbo will not deliver boost the same way the supercharger will. the Stock ecu is programmed to run the car with a supercharger with that boost curve. If you change it theirs only so much fueling adjustment that can be done before you just cant add anymore fuel. the sensors are there to guide the ecu on the map but its not magically going to be able to run something completely different then it was programed to do.
Simply put no matter what you do with it the stock ecu is not going to like it.
Because if it was easy to do and everyone here can think of a solution.
Why is it not being done......
What you really need is a fully programmable ECU and that is not what the factory one is.

 

Plumbing only depends on how you do it some custom kits are ridiculous but not all are like that there is no reason why adding a turbo wouldn't increase efficiency because you no longer need to devote power to turning the supercharger and just like the sprintex you just buy the bytetronik system to tune the ecu.

 

http://www.ebay.com/itm/MINI-COOPER-...50c9f7&vxp=mtr

 

https://www.northamericanmotoring.co...nly-kit&cat=22

 

Too funny

 

One fact neglected here, and mentioned in the other threads about a turbo swap, is the idle boost pressure. From what I gather the MINI ecu is always gonna see boost with the SC, maybe not much at idle but more than it would with a turbo. The way other guys got around this was to simply keep the SC in place. A GT2871 with the M45 could make decent power but, again, internals become an issue at 20psi anyway.

 

Again the ecu needs tuning with something like this the problem everyone had with twin charge kits was tuning and it didn't make sense because the supercharger becomes a restriction at higher rpms.

 

The guys from helix can and will tune twincharge/turbo only kits.

 

So anyone with info on who does a kit or would be able to fabricate one? ABF did one a while back but cant seem to find that anymore....

Some of the issues with turbo mentioned above should be solved with a standalone ECU - extra expense but helps remove some of the headaches plus gives you headroom further down the line if you want to start upping power later on...

From what Ive seen you would need/want: standalone ECU, turbo, turbo manifold and around 15psi boost (plus few extras such as plumbing and pulley since to SC will be gone). If a standard M45 car runs around 15% on stock internals shouldnt a turbo R53 be ok running the same boost? Otherwise you may need to build the engine to cope and that would be where the big costs start... and possibly why there isnt the demand for a 'kit' as it would scare most off - kit for ~£4k but then you have to build the engine for another £4k+ depending on spec....