HJS German imported catalytic converters are made from some of the highest grade materials you can find in a catalytic converter. This yields high performance gains and longevity so it wont deteriorate over time like lower grade catalytic converters. These catalytic converters flow up to 93-95% of a straight pipe in most applications. The benefit is that you get the "straight pipe sound" while still being able to provide enough emissions scrubbing to prevent a check engine light.Â
The 2020 Z4 is BMW’s latest incarnation of the Z4, keeping its reputation alive and well as a powerful and fun roadster. The Z4 M40i dramatically benefits, in terms of sports car sound and power, from a Fabspeed Motorsport Sport Cat Downpipe. You’ll appreciate the more aggressive exhaust note and significant horsepower increase.
These downpipes feature German made HJS 200 cell EURO 6 EC certified compliant trimetallic catalytic converters. We use 4 inch piping from the engine side to the cat, and 3 inch tubing from the cat to the rest of the exhaust. These are the largest and highest flowing catalytic converters you can fit on the M40i 3.0L. Larger catalytic converters are better because they allow for more exhaust flow and the increased catalysts surface area allows for better exhaust gas filtering which means emissions compliance and will NOT trigger a check engine light. Our Sport Cat Downpipes are a direct bolt-on replacement for the factory Supra catalytic converter.
When we looked at the factory 12” long 700 cell ceramic core cats we immediately found an opportunity for improvement. The OEM Cats restrict exhaust CFM flow, limit sound and worst of all, rob performance. Replacing the OEM cats for a set of Fabspeed Sport Catalytic converter will net you improved performance with absolutely zero fear of a check engine light.
Why We Choose HJS Catalytic Converters:
HJS German imported catalytic substrate cores are made by EMITEC utilizing the highest grade stainless steel materials and Tri-metallic precious metal wash coats for high performance street and racing competition usage. HJS German 200 cell Trimetallic Euro 6 HE catalytic converters give the highest performance gains, improved sports car sound and maximum durability. Other brands of catalytic converters immediately deteriorate and fail over time as is typical. Some other companies and brands DO NOT even offer catalytic converters as they know that their catalytic converters will NOT work even when 100% brand new as they have no reliable quality solutions. The HJS German imported HD catalytic converters flow up to 90-92% of a straight pipe in most applications. The benefit is that you get the "straight pipe sound" while still being able to provide enough emissions scrubbing to prevent a check engine light. Typically no P420 and no P430 codes and your car smells clean with no need for a tune to pass emissions testing. It’s a win win solution for a sportier sound, more power, and a cleaner running car which prevents pollution. Not all HJS catalytic converters are the same. Size matters and directly correlated to power, sound, and durability. Fabspeed utilizes the LARGEST possible HJS Catalytic converter for maximum power and sports car sound. No short cuts ever.
FEATURES:
Simple bolt-on installation. Instructions included below
The largest HJS tri-metallic catalytic converter that will fit in the factory location
This HJS catalytic converter will support 1200HP+
Designed to fit Left hand drive and Right hand drive cars worldwide
Significant performance gains across the RPM band. Estimated +35HP gained over the factory unit
Even more power can be unleashed with a ECU tune. Please inquire
No tune required
Superior quality all German and USA components built in house by hand
TIG welded by our expert welders
T304 stainless steel construction
Fabspeed performance products are backed by Fabspeed's Lifetime Warranty
Vehicle Fitment Chart:
MAKE
MODEL
CHASSIS
YEAR
BMW
Z4 M40i
G29
2019-2021
DISCLAIMER: This product removes the OEM catalytic converters from the vehicle, and as such, is strictly intended for closed track events and off-road use only. This product is or contains a Racing Cat Bypass Pipe, which will give you check engine lights on OBD2 cars. We suggest pairing this product with racing software to prevent fault codes and check engine lights. Racing Cat Bypass Pipes are solely intended for track and race cars as they are NOT California Air Resources Board Certified and not EPA certified. You are hereby informed and warned to check your local, state, and federals laws before buying and installing these or any aftermarket parts to be sure whether usage is in violation. All installation-risk and use-risk is borne by the end-user and installer of these parts.
⚠️ California Proposition 65 Warning:
This product may expose you to chemicals known to the State of California
to cause cancer or reproductive harm.
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