lowering compression with a thick head gasket?
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Joined: May 2002
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QUOTE
Aoshi:
Ok this is kinda related. i know there are different sizes of turbos. And the bigger the more torque and hp the smaller the the lower but yeilding less lag. Well If you were to compaire a small turbo boosting at 10psi vs a big turbo boosting at 10psi would the worries of Compression ratios be the same? this is assuming everything in the car is the same except the turbo size.
the larger turbo will yield more cfm of flow, even at the same 10psi of the smaller turbo. i don't quite understand why 10psi is different on any two different turbos, but it's something that is true. dunnoOk this is kinda related. i know there are different sizes of turbos. And the bigger the more torque and hp the smaller the the lower but yeilding less lag. Well If you were to compaire a small turbo boosting at 10psi vs a big turbo boosting at 10psi would the worries of Compression ratios be the same? this is assuming everything in the car is the same except the turbo size.
[ April 21, 2003, 03:00 PM: Message edited by: turbulence ]
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Joined: May 2001
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From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
10 PSI is the same for all turbos, regarless of size. What is different is FLOW, thermal efficency, and air density.
A itty bitty turbo, like the alpine TD-04 has to work VERY hard and spin VERY fast to produce enough FLOW to equal 1ppsi of boost on a motor displacing 2 liters spinning at 6000 RPM. Because it's working so hard, it is not very efficent, and heats the air a great deal to keep that 10 psi going.
a T3/T4 on the other hand has much more flow, allowing it to spin slower, and be more efficent delivering that same flow rate to create 10psi at a much cooler air temp.
Remember, as air heats up, it looses density(this means less oxygen). So 10 PSI of air pressure at 300 degrees is much different than 10 psi of air pressure at 150 degrees.
A itty bitty turbo, like the alpine TD-04 has to work VERY hard and spin VERY fast to produce enough FLOW to equal 1ppsi of boost on a motor displacing 2 liters spinning at 6000 RPM. Because it's working so hard, it is not very efficent, and heats the air a great deal to keep that 10 psi going.
a T3/T4 on the other hand has much more flow, allowing it to spin slower, and be more efficent delivering that same flow rate to create 10psi at a much cooler air temp.
Remember, as air heats up, it looses density(this means less oxygen). So 10 PSI of air pressure at 300 degrees is much different than 10 psi of air pressure at 150 degrees.