Air induction...thoughts?

[Paul-Z]

On my turbo setup, I currently have an intake pipe running from the turbo, down through where the AC dryer used to be, with the filter basically behind the air dam in front of the passenger side wheel well.

Would this be preferred over putting a velocity stack in my high beam and attaching the filter directly to the turbo?

Not sure which would bring in cooler air to the turbo? Or if it would even make a difference...

[downforce22]

Turbos create vacuum to pull air in through the filter. Generally bends and filter create a pressure drop. On a turbo engine, a RAM air effect doesn't really happen because the turbo is already creating a suction effect to pull air into the engine. I don't think there would be much benefit to either. As long as the air under the hood isn't too hot, or has a heat shield there it wouldn't make too much of a difference.

[Paul-Z]

Turbos create vacuum to pull air in through the filter. Generally bends and filter create a pressure drop. On a turbo engine, a RAM air effect doesn't really happen because the turbo is already creating a suction effect to pull air into the engine. I don't think there would be much benefit to either. As long as the air under the hood isn't too hot, or has a heat shield there it wouldn't make too much of a difference.

Appreciate the response. I was thinking more in terms of heat more so than the ram air effect. I’m probably overthinking it. I’m thinking where I currently have it mounted is closer to the road which may carry more heat in the summer vs. up higher at the headlight. Obviously either option is better than just a filter sitting under the hood.

[earthwormjim]

Appreciate the response. I was thinking more in terms of heat more so than the ram air effect. I’m probably overthinking it. I’m thinking where I currently have it mounted is closer to the road which may carry more heat in the summer vs. up higher at the headlight. Obviously either option is better than just a filter sitting under the hood.

I guarantee the temperature increase from compressing the air, will outweigh any tiny temperature differences you'd see from using a cool air source.


Besides, that is what an intercooler is for.

[e30davie]

That is a good point above in regards to the temp increase from compressing the air.
I think its always best to attempt to get some outside air to the air filter. If you look at every OEM setup since forever they have a feed from somewhere with fresh air directly to the air box. OEM e30 has a plastic piece behind the headlight with a hole cut in it with a pipe that goes directly to the air box to make a "cold feed".

I always liked the idea of using the bonnet/hood as the "top" of an airbox and boxing in the pod filter on 3 sides with an air feed from somewhere. Makes for a neat install.

[Paul-Z]

I guarantee the temperature increase from compressing the air, will outweigh any tiny temperature differences you'd see from using a cool air source.


Besides, that is what an intercooler is for.

Good point. Didn’t think about the fact that if you compress air it heats up. I guess I’ll stick with th me way I have it ran now. Never had an issue just rejiggering some stuff so figured I would ask.