Can someone explain exactly how the r56 turbo engine works as far as where air comes from and goes to (CAI>exhaust manifold>turbo>down pipe) and how the intercooler works and what temp it works best with. Thanks

 

but that's not a short subject. Get a book on turbo engines as a start. I've never read one that is complete, but may give a very good grounding on the subject.

Many start with Maximum Boost! by Corky Bell.....

I put a couple of book reviews in the reviews section....

Matt

 

I think he's asking about the routing of the air like where it comes in and how it travels through the process from start to finish... and there is a picture of an R56 motor with arrows depicting this. It is floating around here somewhere and shows it perfectly....try searching for it.

 

except for that part about how the IC works and what temps work best.

Really, I think anyone who wants to get the most out of modern cars should first look at how engines work, then fuel injection, then forced induction. If we all started with some good ol' book learnin' I'm sure the volume of money wasted would be a lot less.

I can't count the number of times I've heard "I'm not getting what I expected" or "the HP gains aren't adding up like when I add all the numbers from the adds" or "I tried this and I think things are running worse"...

a hundred bucks on books will save thousands in parts that either don't work, or don't work together.

Matt

 

This might help.https://www.northamericanmotoring.co...1103281940.pdf

 

here is a very simple very basic universal picture and explanation

1. air gets filtered and sucked through the air panel/cai and into the turbo.
on a mini, air is routed from the front end opening and into the panel filter box
2. From there it gets compressed and heated via turbo
3. compressed air makes way through the fmi to cool the air
4. back up and into the intake manifold
5. in the engine, compressed cold air gets used with the gas
6. the left over gas from combustion makes its way out and into turbo
7. this gas spins the turbo that compresses the air on the other side, step 2
7.5. overboost results in the external wastegate to open (does the mini have one?)
8. finally, out the dp....



the intercooler has a bunch of folds and pleated metal sheets that increase the surface area, allowing hot compressed air to dessipate its heat with the outside cooler air. increasing the surface area makes the air cooler which means it doesnt expand (compresses) meaning you can inject more air into your engine (a nessesary element for proper combustion) Only downside is you tend to drop the boost pressure because as you increase surface area and volume size in the intercooler. How cold do you want the air? as cold as possible... why not?

Here we have the enginge of the mini. You are looking from an angle from the drivers side.
Start at the top right and there is your air filter/cai. underneigth it you can see an exposed hole/pipe. that hole is piped to the front of the car where it gets its air.
Follow the tube from the air box into the snail silver looking thing. that is your turbo compressing the air.
Just underneight that is where the compressed air makes its way out of the turbo, and down into the fmi.
on the other side of the fmi, it goes all the way back up the engine and behind it to be used in the whole combustion process.
to the left of the turbo, there is a cylindrical tube. that is the start of your dp... so after the combustion gas leaves the engine and into the turbo, it enters the dp and out the exhaust.

 

i was reading this pdf and can someone explain to me why on page 20 the second paragraph it says the wastegate is limited to .8 bar? i thought people were running upwards of 18psi on stock vehicles

 

Units check: 0.8-bar = 11.6-psi

Does that help?

 

This website will teach you anything you want to know!


http://www.autozine.org/technical_sc...ech_index.html

 

it's doesn't vent air to atmosphere, but to upstream of the compressor.

Matt

 

wait so if we have one... that releases it upstream to the compressor... does that mean you cant go over 11.6 psi of boost? that doesnt make sense...

 

The blow off valve works two ways. 1. it is a fail-safe incase of the wastegate on the turbo not working and boost goes unchecked to a level that is unsafe at which point the valve opens and vents excess boost. That is why there is a spring in the valve that is at a set tension 2. The DME opens the valve electrically in the MINIs case (most cars it controlled by vacumm) whenever the throttle is closed. What happens is whenever you close the throttle, the boost has no where to go and can cause damage to the compressor wheel because the boost will actually slow the compressor wheel to radpidly which can cause it to break. Thats is why the valve opens and you hear the ppssssst sound on tuner cars when the valve dumps to atmoshere. Our cars don't dump to atmoshere but instead dump to the intake side of the turbo. This does a few useful things like help to speed the turbo back up so turbo lag is greatly reduced. The other is that the air has already been metered by the mass air flow meter and is "accouted for" so it help with the airfuel ratio as well as ecomony.

hope this helps