Turbocharger FlowMaps, calculating best boost for a turbo.

scot-ish

scot-ish

Member +
right, after a bit of a discussion, ive got back into this, not really touched on it since college a few years, and ive forgot the lot haha.

anyways, cam some people give me some advice?

td05 flow chart.
TD05flowMap.jpg


and from that, CFM is marked on at 520, this is a t a pressure ratio of two, which to me is two bar, as its two x atmosphere, at 14.7 psi?

but from this, how do i calculate what pressure this turbo will become less efficient where it then is "only blowing hot air" so to speak, and for the extra boost will hinder the upgrade in performance.

i found this site, which is awesome, has all the flow charts, and they could possibly be "stolen" and made as a sticky.

http://www.stealth316.com/2-3s-compflowmaps.htm

any advice appreciated, and repped, as im kinda pissed of that i cant remember this only from a few years ago haha.

cheers

Jamie
 
G

GP82

Member +
520cfm is based on 15 psi of boost pressure, approx. 2.0:1 pressure ratio.

The compressor charts efficiency islands does not take into account heat exchange.

You could be in the 60% efficiency island and still continue to make good power with 80% plus efficient heat exchange so intake temperature remains low.

Wanna run high boost, make sure you got a good intecooler core, this is where you start looking at intercooler efficiency flow charts!
 
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scot-ish

scot-ish

Member +
right popsy,

im by no means accurate on this, ive made some assumptions.

for example, ive assumed,

ambient temperature- 20 degrees
inlet temperature - 54.5 degrees

ive also made a couple of other minor assumptions.

but from what ive calculated, at 1.8 bar,(pressure ratio 2.9) the CFM is 516. now if looking on the compressor map, that is just out of the max speed of the turbine, so its outside the map, i dont know if ive made a mistake or not, or if the TD05 we run is classed as the "large" one, as there seems to be two of these, if we have the large one, im not sure how to know from comp numbers, then 1.8 bar is fine.

maybe some1 else can help with this, but for the smaller td05 i calculated 1.7bar was max.

as said tho, there are plenty of variables, plus im not sure if my calculations are accurate. i hope some1 else has tht time to try work it out.
 
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popsy09

popsy09

Munster Area Rep.
scot-ish said:
right popsy,

im by no means accurate on this, ive made some assumptions.

for example, ive assumed,

ambient temperature- 20 degrees
inlet temperature - 54.5 degrees

ive also made a couple of other minor assumptions.

but from what ive calculated, at 1.8 bar, the CFM is 516. now if looking on the compressor map, that is just out of the max speed of the turbine, so its outside the map, i dont know if ive made a mistake or not, or if the TD05 we run is classed as the "large" one, as there seems to be two of these, if we have the large one, im not sure how to know from comp numbers, then 1.8 bar is fine.

maybe some1 else can help with this, but for the smaller td05 i calculated 1.7bar was max.

as said tho, there are plenty of variables, plus im not sure if my calculations are accurate. i hope some1 else has tht time to try work it out.
Click to expand...

1.7 bar is still more than 1.6 anyways lol , i wont be going back to the tuners for a few weeks so hopefully we can get a bit more info on it
 
weeJohn

weeJohn

Lifer
All the map will do is plot the turbo efficency at the boost you want to run, with the set up you have. Because ambient temp varies and intercooler effects differ they dont grade it by heat. If you want to check the turbo outlet air temp you need to measure it before (ambient air temp) and after the turbo and compare the 2.

You could use the EP intake temp sensor but it just shows you the inlet mani material temp. Fitting the RIAT intake temp sensor is better for air temp but thats still after the intercooler so its not telling you when the turbo is compressing the air that much its heating it u

So for accurate readings you need at least 2 thermocouples.
 
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