B SweepeR B6

waht is the diff. btw throttle bodies (ITB's) and Air horns? or are they the same thing?

hukares

Gasoline engine have to have throttle bodies to control airflow into the engine. By air horn you must mean like a velocity stack (a bell shaped thing). It is what would normally attach to the throttle body to allow maximum airflow through the throttle body at wide open throttle. You don't want an air horn unless you are a hardcore racer. An air horn is usually run in lieu of an air filter.
-Brian

foz01

Not true, you can enclose the throttle bodies in an airbox and add an in line filter to the airbox.

they give good torque gains throughout the rev range, although on my engine peak bhp ains were approx 5bhp.

BMW //M engines are the only production car engines to use ITB's- most dont due th cost restraints.

foz

Air horns are used when you want a dukes of hazard style horn

Elistan

You're actually talking about three different things.

1) Throttle body. It's that bit the throttle cable hooks up to. It's a short cylinder that has a rotating plate in it in order to control airflow into the engine. The S2000 has one of these that the intake hooks up to. (Air then goes into an intake manifold and eventually into the engine...)

2) Individual throttle bodies. (ITB.) Simply, each cylinder has it's own throttle body.

3) "Air horn," more commonly called a "velocity stack." It's simply a particularly shaped opening on a tube so that air can flow into it in the most efficient manner. The PRM intake has on at its end, for example.

Destro

True, though it wasn't that long ago that the Ferrari F355 had ITB's (not sure I remember why the 360 Modena changed that, you're probably right about it being cost).

B SweepeR B6

my mistake i dind't mean throttle body as in just a reg. one i know what that is. thats why i put (ITB) next to it so ppl knew i meant Individuals and nto a reg. throttle body. sorry my mistake.

FO2K

My 69 911S came with velocity stacks and a large air filter that fitt over all six stacks.