[mwebb]

Originally Posted by tru

by reducing the size of the intake, do you not reduce horsepower?

reducing horsepower would be more beneficial at idle i would think. if you could test to see how your gph changes when sitting at a stop light with your restricted intake. this may not be worth anything at speed but may be beneficial at idle

restricting intake tube diameter MAY reduce maximum available power output , but it also may be an improvement to FE and BSFE at cruise and lighter loads as the velocity of the intake charge will be increased with smaller diameter intake runners , which will improve volumeteric efficiency - your results will vary depending on how it is done -

depending on what is restricted , and how it is restricted , FE can be improved or UN changed , maximum power output , torque and horse power will be always be reduced , a restriction plate in the air filter will never improve FE , but up to 50% restriction , will not degrade FE either