air filter size effect on power
#1
air filter size effect on power
For turbos with 4" inlets, has anyone done any dyno testing of no cone filter vs a filter? Or ow about a smallish filter (b/c of fitment issues) versus larger ones in applications with more space? I'm talking about filters placed directly on the turbo inlet or with a short inlet duct, no "cold air" setups.
#3
Rotary Enthusiast
For turbos with 4" inlets, has anyone done any dyno testing of no cone filter vs a filter? Or ow about a smallish filter (b/c of fitment issues) versus larger ones in applications with more space? I'm talking about filters placed directly on the turbo inlet or with a short inlet duct, no "cold air" setups.
This was with a T04S, .84 A/R P Trim on a Renesis.
I'd like to specify that the filter I use is tiny(about 3-4" long) due to space constraints.
Chris
#4
My K&N was small too but no bend just straight off the turbo.. We did one run and immediately did another with the filter off back to back and netted no difference at all. no changes were made. Im sure the quality and size of the filter makes a difference the k&N's must flow good.
#5
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A small filter will not significantly affect power unless it is so small that it becomes a restriction. If a filter is not a restriction to flow, increasing the size to a larger filter will have zero effect on power, but it will not get dirty as fast as the smaller filter.
As for any horsepower gain, it is a percentage and not a fixed number. For example, were I a slick businessman trying to sell my filters, I would test one on a 3,000hp engine and advertise that my filters can gain up to 40 hp! Of course, it would only add about 2 hp to an otherwise stock 13B, but I did advertise "up to" 40 hp. Also, turbocharged engines see more of a gain with high-flow filters because turbos multiply pressure.
For K&N brand filters, I derived the stupid Evil Aviator K&N filter rule of thumb, which hopefully isn't any more stupid than the other stupid internet guidelines:
Horsepower Potential = Filter Media Area square inches * 4.53
If in doubt, just go to the next larger filter size as it will not hurt anything. If you have limited space, then just get the filter with the most filtration area possible.
As for any horsepower gain, it is a percentage and not a fixed number. For example, were I a slick businessman trying to sell my filters, I would test one on a 3,000hp engine and advertise that my filters can gain up to 40 hp! Of course, it would only add about 2 hp to an otherwise stock 13B, but I did advertise "up to" 40 hp. Also, turbocharged engines see more of a gain with high-flow filters because turbos multiply pressure.
For K&N brand filters, I derived the stupid Evil Aviator K&N filter rule of thumb, which hopefully isn't any more stupid than the other stupid internet guidelines:
Horsepower Potential = Filter Media Area square inches * 4.53
If in doubt, just go to the next larger filter size as it will not hurt anything. If you have limited space, then just get the filter with the most filtration area possible.
#6
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I remember reading a thread a long time ago..
ReTed had a 20B they were tuning
by removing the filter the A/F ratio went leaner by a whole point!
so I guess it depends on the application and filter itself as well
I ran no filters on my stock twins the other day.. I swear it sounded like a T51-R!
so mean!
ReTed had a 20B they were tuning
by removing the filter the A/F ratio went leaner by a whole point!
so I guess it depends on the application and filter itself as well
I ran no filters on my stock twins the other day.. I swear it sounded like a T51-R!
so mean!
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#9
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The dyno looks fairly typical, showing that the filter is doing its job of straightening out the air and increasing the torque, but the impact of the pressure restriction is seen at the high rpm end. Although we are dealing a bit with voodoo math here, it looks like the filter is a bit small for the application.
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