Whats the deal with Throttle Body Spacers for tC

[RacerX7624]

Ive seen em around and it seems like a pretty cheap mod....does anyone know if they actually improve anything? The tC is my girlfriends.Its fairly new and Ive already installed a Injen CAI.

[RacerX7624]

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[Soulbane]

Aside from perhaps slightly better response, there isn't much going for this mod to consider it as a necessary first mod.

[Speedstar]

I know on the K20z1 motor it was actually proven to take Hp away from the engine, but that is a K20...but that was also when VTEC kicked in.

I dont know if that would happen to this motor.

[navylife59]

Total was of money, unless you need a port for NOS sprayer. A shop in Puerto Rico actually dyno tested and produced the same results; less HP and just about the same TQ.

TB spacers are for carburation. A carb mixes the air and fuel just before the butterfly valves. FI mixes air at the intake runner just before the intake valve. Changing the plenum volume on the latter will not change the air volume gauged by the MAF sensor.

The secondary effect that TB spacers have on carburation performance is heat conduction via the intake manifold that causes vapor lock in the carb. Again, this has no effect on FI, in regards to the 2AZ-FE, as the fuel is mixed with the air in the intake runners and the intake manifold is plastice.

What hurts performance on these TB spacers is the "swirl-effect" or "helix" as they claim. What is the quickest point from point A to B? A straight line, so what happens when the air supposedly twist like a tornado? You end up with a low pressure area surrounded by a high pressure vortex. This actually causes the gas to form droplets, not atomize equalling a loss in performance.

If you do use one for a NOS port, then maching out the Helix and you will be golden.