NZ951

Hey,

I thought, It may be more stable and "better" to run of WG pressure only and use my foot controller to control boost. This means putting in a 1.4 bar spring. As that is the max I want to run. Firstly, is this the best way to run boost if I dont want to run less ever? Ie boost hits hardest this way etc. Secondly, anyone got a .4 bar spring?

Anyone got a 60-1 HIFI compressor map? I want to ensure this is in the efficiency zone I want.

NZ951

Bump

Luke

If you want to find a "real" efficiency, you'll need a turbine map as well

NZ951

Ok, so a stage 3 wheel map too please...

BoostGuy951

You will not find turbine maps in anything short of the GT series from Garrett. AFAIK, the GT series are the only turbines that have published maps.

NZ951

The 60-1 is a turbonetics turbo...

NZ951

Now were are talking! So how many lb/min do you think I am flowing?

BoostGuy951

My estimates for a 2.5L with a open intake, free flow exhaust and assuming a free flowing turbine larger than #6.

Here are some numbers for you to go by:

3k.........7 lb/min
4k.........10.6 lb/min
5k.........12.5 lb/min
6k-7k.....14 lb/min

These are estimated air consumption values at 1 bar absolute (0 psi). To get the values at a given boost level multiply by the absolute pressure in bar.

Have fun!

NZ951

Ok, so at 1.4 bar we get 33.6lb/min which puts it above 65% still... Phew.

Danno

Uh, 1.4-bar (20psi) of boost is actually 2.4-bar on the compressor maps. The vertical scale is the pressure-ratio of the incoming vs. outlet air. So you have 1-bar absolute going in and 2.4-bar absolute going out.

Here's some more numbers of desired flow-rates:
And plotted on those two compressor maps, we get this (both maps scaled to same axes):


What that means with the desired flow (purple dots) being above the surge-limit (maximum-boost turbo can generate at certain flow-number), is that you'll get less than the desired amount. So you can drop down from the desired flow-volume to the surge line (red arrows). This will give you the true boost-level at that flow amount (arrows actually need to aim downward left, but close enough). So the actual full-throttle boost-levels will be more like:
You'll have lots of lag and won't hit your target 20psi boost until about 6000rpm.

NZ951

Did you consider my mods when you got those flow numbers? Or are they from stock units?

NZ951

Also, that is not te map for the HIFI version, it would be slightly sifted to the left and rotated to the left also yes?

Bengt Sweden

Hey NZ,
regarding your question about running just WG. No it is not ideal. With electronic control you can make sure that the WG is closed when you are below desired boost and that it opens sufficiently when required to control boost. This will give you the best response.

Then my view on boost control is that the EBC should use flow input for control and not boost + TPS which I belive the KLR has.

Bengt

TonyG

I don't know how or why those compressor map plottings got so far off... but here's a 2.5L 951 engine plotted against a 60-1HiFi compressor map.

See previous post:




Pressure Ratio (PR) which is the Y axis is (at sea level)

14.7 + boost pressure
__________________

14.7


20psi = 2.36 Pressure Ratio

NZ951

And the pheonix has risen from the dead! Nice to see you back TonyG! So in reality, the 60-1HIFI is better than the previous analysis. Good to see... I guess time in the car tuning will tell!