Why the aftermarket throttle bodies?

[Wildcat]

Tune, CAI, and changing axle ratio offer the best bang for buck.

If you're concerned about warranty, Ford might offer two or more of those three in a kit that's warranty approved.

Throttle body is a waste of money on a mostly stock or lightly modified car.

Sponsored

 

[mustanghobo]

As someone new to mustangs and american muscle in general, can someone explain to me why having a special throttle body or otherwise aftermarket throttle body has the ability to make horsepower gains? Is it purely because the aftermarket body you would get would be a larger diameter and allow more air?

If it's that simple, why didn't Ford make it sized properly in the first place?

I notice even Ford Racing sells these throttle bodies for their engines. I hope to get a 2015 'stang and want to know all the easy bolt-ons while keeping it NA. I may go FI later on.

Thanks for asking! I've always been a mustang fan, never an owner yet and was wondering the same thing.

From what I read it seems, unless you're modding the engine with exhaust, CAI, etc the throttle body isn't gonna have a huge effect.

 

[5th-Stang]

Factory engine offerings are always a balance...of power, efficiency, reliability, and yes, can't forget the bean coutners...cost.

 

[86GT]

Newer cars typically only need a bigger TB if you're going with a supercharger. The bigger diameter helps with increased air flow.

It's also important to note that you should never have a TB bigger than the air inlet in the intake manifold. I always laugh when people build their foxbodies with 75mm TBs even though the inlet into the manifold is only 65 or 70mm. At that point you're just creating a bottleneck.

 

[Wade]

I have no doubt they squeezed every HP they were allowed.

Sorry, but bean counters always win. There's plenty of guys that will give up driveability and MPGs for more power, it's what hot rodders have always done.

Not necessarily.

For one, they have to balance HP with driveability, performance with EPA requirements (emission, fuel economy), and target demographic income. Could they wring out more performance with a less safe tune from the factory? Sure. But what ancillary requirements does this negatively effect? Can it clear emissions? Are they now below the federally mandated 42mpg or whatever average for all cars across their product line?

This statement by the Ford guy was a bit disingenuous though:

I don't discourage it, but I also can't stand here and say that we would stand behind it

A little too much lawyer speak for my taste. They can and should encourage it, under the pretense that it can and will void the warranty. It does Ford's public image good when they are friendly with tuners and aftermarket companies.

Sponsored