Perrin Inlet hose: Is it legal for C Street?

[imnotsureaboutbrz]

So the regs say:

G. Silicone replacement hoses are permitted as alternate components provided they meet the requirements of Section 13.0 with regard to size,
shape, location, and performance equivalence. Replacement induction
system air intake hoses must also match the standard part in stiffness,
contour, and internal wall texture.

But then it also says:

A. The engine air filter element may be removed or replaced provided the air
flow path remains as originally designed (i.e., no additional openings). No
other components of the air induction system may be removed, replaced,
or modified.

So is replacing the inlet hose (keeping OE airbox) with a silicone hose is good, but the resulting modification (removing sound tube) makes it an illegal mod?

[M0nk3y]

Originally Posted by imnotsureaboutbrz

So the regs say:

G. Silicone replacement hoses are permitted as alternate components provided they meet the requirements of Section 13.0 with regard to size,
shape, location, and performance equivalence. Replacement induction
system air intake hoses must also match the standard part in stiffness,
contour, and internal wall texture.

But then it also says:

A. The engine air filter element may be removed or replaced provided the air
flow path remains as originally designed (i.e., no additional openings). No
other components of the air induction system may be removed, replaced,
or modified.

So is replacing the inlet hose (keeping OE airbox) with a silicone hose is good, but the resulting modification (removing sound tube) makes it an illegal mod?

I'd argue silicon hose provides a performance gain due to the change in contour and shape of the hose. The stiffness of the hose also is different from OE.

This is more relating to an old intake hose that may be brittle/torn and can be replaced with an OE equivalent.

Removing the sound tube regardless is illegal.

[TrqlessWonder]

Originally Posted by imnotsureaboutbrz

So the regs say:

G. Silicone replacement hoses are permitted as alternate components provided they meet the requirements of Section 13.0 with regard to size,
shape, location, and performance equivalence. Replacement induction
system air intake hoses must also match the standard part in stiffness,
contour, and internal wall texture.

But then it also says:

A. The engine air filter element may be removed or replaced provided the air
flow path remains as originally designed (i.e., no additional openings). No
other components of the air induction system may be removed, replaced,
or modified.

So is replacing the inlet hose (keeping OE airbox) with a silicone hose is good, but the resulting modification (removing sound tube) makes it an illegal mod?

That's going to be a hard no.

http://perrinperformance.com/i-13324...-fr-s-brz.html

3" DIAMETER FOR MORE FLOW
The PERRIN Inlet Hose has a 3.0" internal diameter compared to 2.7" found in the OEM part. This allows for a greater amount of air to smoothly enter your engine with virtually no restriction. This larger diameter will easily support all bolt on modifications especially aftermarket cams.

So, it has a bigger ID for more airflow.

SMOOTHER AIR FLOW TO THROTTLE BODY
The PERRIN Inlet Hose is perfectly smooth on the inside and has a larger radius bend toward the throttle body. Compared to the stock part, which has a very sharp bend, our PERRIN Inlet hose makes a much more gradual bend toward the throttle body making for even less restriction. This along with removing the pleats found in the OEM hose, makes for more horsepower, and improves acceleration.

And it has both a different contour and internal wall texture.

SS INTERNAL SUPPORT WIRE
The PERRIN Inlet Hose is reinforced with a stainless steel support wire that is embedded within the silicone layers. The support adds rigidity to the hose and prevents collapse when used with restrictive filter elements and high horsepower cars running higher redlines and big cams.

And it's stiffer than the OE hose.

REMOVES RESONATOR AND SOUND TUBE
The PERRIN Inlet Hose removes the sound generator tube, and lower resonator box to allow for a much smoother air path from the intake to the throttle body. This also cleans up the engine bay be removing all the added hoses for these two components.

And changes the airflow path in another fashion.

So, this is pretty flagrantly afoul of the regs you cite.

Something to keep in mind when looking at allowances. Just because a type of allowance exists, doesn't mean there is a legal way to take advantage of it. This is one of those times.

[imnotsureaboutbrz]

Dang it, why do the STX guys have all the fun bits. I guess I'm staying in Cheap Skate, I mean C Street...

Thanks guys for confirming it for me!