The best turbo for a 998?
Turbo Mini Forums

Thanks for the links wil
It sounds like alot of tinkering to get it to work, and the gt1544v is definiately too small according to that guys experience with it,
so as paul s said earlier the GT1749V would be better, i wonder what kind of results fitting one would give,

A job worth doing is a job worth over doing

Schrödinger's cat - so which one am I ???

Diesel use vacuum actuation because they are fitted as standart with a vacuum pump in order to have brake assist.

Rusty by nature

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I spent the day thinking of simple ways to get a vnt turbo to work in a 998 engine and i came up with a rather crude way of controlling the boost when using megesquirt.
Just wondering what ye think of it, wheither it would work or fail miseribly.
Dont be too hard on me if im wrong, still getting to grips with all the turbo stuff, so dont shoot.

Heres the link to my 3D CAD drawing of my idea

http://i1226.photobucket.com/albums/ee420/...1/Untitled1.jpg

Edited by jdisel on 10th Oct, 2011.

A job worth doing is a job worth over doing

Schrödinger's cat - so which one am I ???

theres somthing about vane angles relating to efficiency in here.

http://www.google.co.uk/url?sa=t&source=we...JLlp-zg&cad=rja

Nice find Joe,

It gets interesting from the bottom of page 23 onwards.

At least their diagram matches my photo !!!

Bedtime reading.

I wonder if the Capobianco & Gambarotta (1992) paper is available online :)

Interesting comment about the VNT design being considered poor for the higher temperatures of spark ignition engines (although obviously technology moves onwards and some of this research is quite old now).

Schrödinger's cat - so which one am I ???

http://scitation.aip.org/getabs/servlet/Ge...gifs=yes&ref=no

Edited by Paul S on 10th Oct, 2011.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I think at that point the link is talking about constant flow, (only skim read it)


bit more bed time reading for you....

http://b-dig.iie.org.mx/BibDig/P07-0673/da...T2007-27562.pdf

Schrödinger's cat - so which one am I ???

Apparently most automative turbines have around 50% reaction according to Winterbone, so I will concede on that one.

I still think that all the flow has to go through the wheel so accurate sizing is essential if you want maximum power.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

For information, data from my simulation of a balls-out 998 5 port on 12 psi, 7.5k, Gt17

Compressor flow 0.137 kg/sec
Wastegate flow 0.049 kg/sec

Therefore turbine flow 0.088 kg/sec

So that 150% will just about cut it.

EDIT: Not sure that this tells us anything other than a VNT25 can be used in a GT17 application without a wastegate.

Edited by Paul S on 10th Oct, 2011.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

just looking through ebay and it would appear that the gt1549 from the rover 25/45 diesels is already in the correct orientation to fit on a mini.
not exactly ground breaking info, just thought it might be useful for someone.

one day boost will be mine!

Edited by jdisel on 13th Oct, 2011.

A job worth doing is a job worth over doing

thats exactly what I'm working on now,

I fitted the FET tuesday ahd had it controlling a valve from a scooby, just sneed to bung it on the car and map the boost now.

I also want to try driving an RC servo tomorow.

I really like the MS, but for the MS2 you need to be a bit of an electronics dabbler, MS3 will do a lot with no mods.

I recomend DIY autotune for MS stuff,

as for what it can do over MJ... injection (but tbh thats a whole other topic on the 5 port), mappable boost, programable outputs, idle valve control, launch control,

but the best thing about MS is what you can log... TPS, MAP, Coolant temp, manifolt temp, AFR, RPM, and all the outputs from the ECU like Advance, injector PW, ilde valve position, ect.

you can log upto about an hour in my experience, heres some screen grabs of what the logs look like.

MS3 is an expensive bit of kit but looks impressive, can the MS2 be easily modded with basic soldering skills to give the same result, Is it MS2 or MS3 you man used in the link i left in my previous post.

Are you using a boost actuator to control the vnt,
would using a vacume pump and the standard actuator with a high speed valve work too.

A job worth doing is a job worth over doing

in that link its actually an MS1 on a version 2.2 PCB, probably with the MS1 extra code programmed into the chip.

Yes I'm using a boost actuator, My current turbo came with it as std,

you could use a vacum pump and the std actuator and valve ( thats what they do on a lot or production deisils), but IMO it will be easier to swap the actuator rather than rig up a pump,

Do you just download the MS1 extra code off the net for free or has it to be bought,
My thinking behind it is that the vacume pump would give more predictable results than using boost and it would not be affected by engine load or would it make any difference.

A job worth doing is a job worth over doing

yep, you can just download the extra code,

If you use a vacum pump I think you'd be able to control the boost at low boosts better, and also you would be able to keep the vanes open at cruise.

Also Jeans up coming rugedized MS is worth a look too, probably over kill though unless you are injecting.

I think ill be adding a megasquirt setup to my long list of bits i need,

Let me know how well your vnt project goes joe.

A job worth doing is a job worth over doing