2560 vs 2860 boost numbers...
#21
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1. A steep surge limit line indicates that the turbo will produce high boost pressures at low cfm before surge is produced. A surge line that leans sharply to the right, indicates that the turbo will not work at high boost pressures at low airflow rates.
2 & 3. It doesn't sound like you are calculating and reading the map correctly. What turbo? what power goal? Try reading turbobygarrett.com "turbo tech 103"
2 & 3. It doesn't sound like you are calculating and reading the map correctly. What turbo? what power goal? Try reading turbobygarrett.com "turbo tech 103"
RPM points were 3000-4000-5000-6000-7000
VE was 80% across the board
Compressor efficiency was whatever my map said it would be when i punched in the boost and got a flow calculation.
Bore was 3.307in
Stroke was 3.346in
Cyl 4
Air Temp 20C
Intercooler Efficiency 70%
Basically I put in the values initially shaped on a T3-60 map, then used the lb/min numbers to cross reference it to a GT2560 map and make some adjustments.
My aim was to get the torque up to ~200lb-ft as fast as possible and hold it there as long as possible without heat-soaking my old Flying Miata intercooler.
#24
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RE: 18psi for 300hp, I built the spreadsheet from the tech103 article and Corky's book. I then scaled/fudge factored so that the numbers matched several real-world examples I'm aware of for 240hp at 12psi. 18psi for 300hp is what came out of that.
#25
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there are so many factors, it's really impossible and wrong to say 18psi = 300rwhp. Remember Paul has made both 270rwhp and 300rwhp at 14psi on his 2560 all thing but the intake manifold being equal.
#28
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They are plots to show where on the compressor map the flow would fall at any given pressure ratio.
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#32
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That's very encouraging.
According to Paul's sig he has better exhaust flow than I will which means I probably won't hit that kind of topend power. But it looks like he ran a flat amount of boost. I've got a ported/polished head with big backcut valves, so hopefully I can hold ~250lb/ft through the midrange with a strategically shaped boost curve.
What kind a fuel was that on?
According to Paul's sig he has better exhaust flow than I will which means I probably won't hit that kind of topend power. But it looks like he ran a flat amount of boost. I've got a ported/polished head with big backcut valves, so hopefully I can hold ~250lb/ft through the midrange with a strategically shaped boost curve.
What kind a fuel was that on?
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I use that spare AIT to plug the bung, I have yet to buy a real 3/8" plug for it. The AIT sensor is connected and installed out of the engine bay just after the IC.