TonyM995
Registered
To keep this conversation going and talk about ideas that are worth sharing.
It appears that understanding Pressure Ratio is more important than boost pressure. This makes sense because today I did a training on Fuel Pressure Regulator- the FPR is referenced to manifold pressure. They said if there is 45 lbs of fuel pressure on the top of the injector and 45 lbs of fuel pressure on the bottom of the injector, no fuel would flow.
Shane T talks about pressure ratio a few times. At the 1:20 he says "So it takes the least amount of horsepower to get the most amount of boost". I hear this and think efficiency matters. Then at the 7 minute mark he says "What the engine effectively knows is pressure ratio across the cylinder".
Just past the 8 minute mark seems to be the most important part of this video. Please watch that section. He says "when the back pressure is the same across the engine. The Volumetric Efficiency is the same as it would be when normally aspirated".
You can run the kit posted but I'd bet that it's not remotely close to efficient because it's causing excessive back pressure to the cylinders. Which means it will take more boost to have a 1:1 pressure ratio compared to a well-designed header.
Additional reference- "Why you should be way more concerned about Pressure Ratio than “boost”
www.efi101.com
It appears that understanding Pressure Ratio is more important than boost pressure. This makes sense because today I did a training on Fuel Pressure Regulator- the FPR is referenced to manifold pressure. They said if there is 45 lbs of fuel pressure on the top of the injector and 45 lbs of fuel pressure on the bottom of the injector, no fuel would flow.
Shane T talks about pressure ratio a few times. At the 1:20 he says "So it takes the least amount of horsepower to get the most amount of boost". I hear this and think efficiency matters. Then at the 7 minute mark he says "What the engine effectively knows is pressure ratio across the cylinder".
Just past the 8 minute mark seems to be the most important part of this video. Please watch that section. He says "when the back pressure is the same across the engine. The Volumetric Efficiency is the same as it would be when normally aspirated".
You can run the kit posted but I'd bet that it's not remotely close to efficient because it's causing excessive back pressure to the cylinders. Which means it will take more boost to have a 1:1 pressure ratio compared to a well-designed header.
Additional reference- "Why you should be way more concerned about Pressure Ratio than “boost”
Pressure Ratio - EFI University
Why you should be way more concerned about Pressure Ratio than “boost”
www.efi101.com
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