New Stuff

Porsche GT3 vs. GT4 RS Exhaust: Valvetronic Sound and Dyno Test

On Sep 11, 2026By Kies Motorsports / 0 comments

Bryan with the Porsche GT3 and GT4 RS and a Valvetronic titanium exhaust

Compare the Porsche 992.1 GT3 and 718 GT4 RS with Valvetronic titanium exhausts, stock and final dyno results, sound impressions, and configuration differences. Read more

BMW F97 X3 M and F98 X4 M exhaust sound comparison

BMW F97 X3 M & F98 X4 M Exhaust Sound Comparison

Compare dAHLer, AWE SwitchPath, and Valvetronic exhaust sounds, configurations, and current pre-shipping prices for the BMW F97 X3 M and F98 X4 M. Read more

On Aug 26, 2026By Kies Motorsports / 0 comments

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OFF-ROAD USE POLICY & EMISSIONS COMPLIANCE NOTICE

California Proposition 65 Warning:

This product can expose you to chemicals such as lead and lead compounds, which are known to the State of California to cause cancer or birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.

For a complete list of chemicals known to cause harm, visit https://www.p65warnings.ca.gov/chemicals.

EPA / CARB Compliance & Legal Use:

Under the federal Clean Air Act (42 U.S.C. §7522(a)(3)), it is illegal to manufacture, sell, install, or use any part that defeats or alters a motor vehicle’s emission control system for use on public roads. Unless a product has received an Executive Order (EO) from the California Air Resources Board (CARB), it is not legal for use or installation on any pollution-controlled vehicle driven on public highways.

Civil penalties up to $4,819 per violation per vehicle
Possible criminal penalties under the Clean Air Act
Revocation of registration or smog certification by DMV or local authorities

State & Local Regulations:

Some states have CARB-equivalent or independent emissions laws. Customers are responsible for verifying local regulations before purchasing or installing emissions-related products.

Intended Use & Customer Certification:

All performance, racing, or competition parts sold by this company are intended solely for off-road, closed-course, or competition use on vehicles that are never registered or used on public highways.

I have read and understood the California Proposition 65 Warning. I have read and understood the EPA/CARB Compliance Notice. I understand these products are intended for off-road or competition use only. I acknowledge that it is my responsibility to comply with all federal, state, and local emissions laws. I understand that installation or use on a public road vehicle is a violation of the Clean Air Act and may subject me to personal liability.

Company Policy Statement

Kies Motorsports, LLC sells and markets these products for lawful use only. We do not condone or authorize the use of emission-control defeat devices or any modification that violates the Clean Air Act or state regulations.

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