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Mihnea has already convinced me these are the way forward with their high flow i'm just looking for specifics on airflow

i'm going to use rs4 heads, hopefully tubular manifolds, but probably standard 2001.5 IM, budget is killing the mods ! so what kind of flow can they give 3000-8000rpm+ when do they run out of puff...

thanks

dummi wrote: when do they run out of puff...

thanks

Long after your licence......

dummi wrote:so what kind of flow can they give 3000-8000rpm+ when do they run out of puff...

thanks

Need to get a compressor map to work that out

and here they are.. just need to learn how they work now so i can read them

http://forums.audiworld.com/s4/msgs/1835636.phtml

after much studying (not really)... at 70% volumetric efficiency the compressor map is further to the right .175 for rs6k04, .158 for rs4k04 ... how the volume exactly converts into rpm in numbers i don't know.. i don't really know what i said there making this is a topic that needs further research

That turbo can make 1.4 bar all the way to 7k and still stay @ around 73% efficiency.

1.4 bar is all it is good for really but it can flow loads of air.

It flows more than the K16 bottom end but slightly less the the straight RS4

Sorry not got the time to work out revs etc as I am at work I will though when I get home unless someone else does it.

thanks Paul thats plenty to be going on with

Ok here you go.

this is just on paper remember turbos can act differently in real life but it gives you a pretty good representation of what it will do

Dots 1 to 12

1= 1bar @ 2800rpm
2= 1.1bar @ 3000rpm
3= 1.2bar @ 3200rpm
4= 1.4bar @ 3500rpm
5= 1.4bar @ 4000rpm
6= 1.4bar @ 4500rpm
7= 1.4bar @ 5000rpm
8= 1.4bar @ 5500rpm
9= 1.4bar @ 6000rpm
10=1.4bar@ 6500rpm
11=1.4bar@ 7000rpm
12=1.4bar@ 7500rpm

What top end mods will you do to allow you to rev to 8k ?

top end? do you mean bottom end? lightened crank , uprated rods. should be able to get more than 8k out of it... HTH?

Those spool up figures look about spot on and in-line with what I'm getting but they can provide loads more boost than that, Mihnea was going to have mine peaking at 1.7 I think with 1.5 at redline. I am still running std cats but they should spool up quicker once they have been changed for 100cell jobs...

dummi wrote:top end? do you mean bottom end? lightened crank , uprated rods. should be able to get more than 8k out of it... HTH?

I think you will need to do something with the valvetrain as
well to get to 8K+

@paul thanks theres plenty there then

@jonnyx yeah i've been looking at mechanical lifters, its just out of my budget right now, more likely next year. topend is heads rs4 with rs4 cams, revolver do some street cams and more aggressive race cams i'll be looking at..

Yeah I am sure you could run more than 1.4bar but I just plotted a graph relevant to the compressor map you see.

1.4bar @8k would be a flying machine

FYI...I think you'll find the NA heads from the 2.8 flow approx 30% more air.....