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Q: What Catalyst should I choose?

A: This depends solely on what the car will be used for, and you have to consider many factors such as tuning, track time, emissions wanted/needed depending on the country/state you live in. Ideally, you want the largest converter possible, the smaller the catalyst the less heat it can take, and less gasses it can convert to do its job properly.

If not tuning, or you need an error or CEL free solution based on our experiences and testing in the field we have made a list on what has worked, to view the list please click here. Please keep in mind this is not a guarantee but something to help future clients make the best decision for them. When wanting to be CEL free and not tune using the largest catalyst size is highly recommended.

When choosing a catalyst on our CEL free guide, 02 Spacers are NOT needed. 

We offer (Catless) Competition Downpipes and high flow catalyst from the best converter manufacturers in the world HJS and Gesi. HJS converters are 200cpsi (cell) and are made in Germany and Gesi converters are 400cpsi (cell) and made in Canada. 100cpsi (cell) catalyst can be requested on special orders only. 

We have pre selected catalyst choices on every product that we feel work best for the platform, if you would like a size not listed, just ask us and we will add it. 

Made in Germany HJS 200 cell Ultra High-Performance converters are known as the industry leader for their characteristics, quality and durability with being able to have a flow rate of 93% opposed to a straight pipe, they can get away with this flow due to their special wash coating used on their substrate. This washcoat is expensive hence the price. Our HJS Converters are Euro6 rated suitable for most countries' requirements and have a power holding capacity up to 1200hp.   Please read more about HJS converters here.

Made in Canada Gesi GEN2 converters are a 400 cell catalyst that is one of the best for emissions for newer vehicles. The Gesi converters have a flow rate of around 80-85%. Our Gesi Converters are EPA Compliant, will pass most emissions inspections worldwide and have a power holding capacity anywhere from 850-1200hp depending on the size you choose. Please read more about Gesi converters here.

Catalyst CEL Free Guide Video and Cat Information

Q: What is the heat shielding option and do I need it?

A: Our heat shielding is proprietary in nature, integrating a 5-8mm ceramic wool underlayer, enveloped by a meticulously formed stainless dimpled foil. This intricate process is facilitated through manual craftsmanship and secured to the pipe via 3D printed molds and dies. Notably, this shielding precipitates a temperature reduction exceeding 50%, surpassing alternative coatings or wraps employed by others. It's imperative to recognize that heat shielding lacking a proper air gap, represented by ceramic wool, renders the protective function non-operational.

We advocate for the inclusion of the heat shield option in a substantial number of cases, particularly for vehicles with downpipes that connect directly to the turbos, particularly those situated within the transmission tunnel. This decision contributes to heat mitigation, maintaining optimal turbo temperatures, reducing engine bay and intake air temperatures (IAT). Addressing the catalyst query hinges on user intent, considering factors such as intended track usage and the aspiration for consistent performance devoid of timing retards and heat retention.

An added advantage of the heat shield resides in the ceramic wool pipe insulation. Discernibly, a more refined, harmonious auditory profile emerges compared to the coarser raspiness commonly associated with the replacement of OEM downpipes. Client feedback attests to diminished in-cabin vibration (NVH) and an overall enhanced exhaust note with the inclusion of this option.

Q: How do I use the tunable 02 spacer?

A: Oxygen sensor spacers have remained a longstanding solution. They serve the purpose of deceiving the Engine Control Unit (ECU) into perceiving accurate sensor data from the vehicle, particularly in situations where tuning is not employed. In scenarios where competition catless models—employed for odor reduction—yield an unintended Check Engine Light (CEL), these spacer restrictors can be deployed to rectify the sensor data, preventing error-related complications.

To be used on the lower (post cat) bungs. Comprising of three distinct inserts (referred to as "pills"), these spacers offer adaptability. Typically, initiation with the middle-sized insert is recommended. Resetting the ECU before vehicle ignition is essential. Subsequent to normal driving, the absence of a CEL indicates a successful outcome. However, should a CEL occur, swapping to a larger or smaller pill and repeating the process is advised. Low efficiency codes means the spacer insert is too large. Subsequently getting a slow response/rich to lean code means the insert is too small. 

When following the Catalyst Check Engine Light Free guide, 02 Spacers are NOT needed.

02 Spacers CANNOT be used on a OPF equipped vehicle, as tuning is mandatory for those cars. 

Q: Do I need new gaskets?

A: When embarking on exhaust installations, particularly involving compressed or turbo flange components, the judicious practice entails the use of new gaskets to ensure optimal results. While flat double-wall stainless gaskets can often be reused, we advocate for their replacement if the vehicle's mileage surpasses the 40-50K threshold. Worth noting is that OEM gaskets are universally compatible with all Redstar Exhaust Products.

Q: What is OPF and how do I know if I have it?

A: The OPF, or Otto Particulate Filter, is a specialized particulate filtration system mandated by stringent emissions regulations in regions such as Europe and Australia, predominantly on vehicles manufactured in 2020 and beyond. Downpipes for such systems typically feature additional thermocouple sensors and pressure tubes. In some instances, these components are also present in mid pipes. Tuning becomes a requisite in approximately 90% of cases, and our products include supplementary bungs on the pipes to accommodate the OPF and ensure seamless integration with all original equipment manufacturer (OEM) attachments. Should you be uncertain about the presence of an OPF in your vehicle, providing your Vehicle Identification Number (VIN) before placing an order is advisable.

Q: What size piping do you use?

A: With over a decade of manufacturing experience since 2011, our products undergo rigorous testing to ensure exceptional quality. We incorporate various pipe sizes, moving beyond a one-size-fits-all approach—sizes like 4 inches, 3.5 inches, 3 inches, 2.5 inches, etc., are used as needed, unless explicitly indicated in the product description. We caution against oversimplifying product comparison based solely on size, as optimal power enhancement requires a more nuanced consideration. Feel free to specify your size preferences in the order notes section.

Q: Who do you recommend for a tuner to pair with your Downpipes?

A: To pair your Downpipes and Exhaust with a ECU or TCU Tune we highly recommend Eurocharged.

  • Visit their website or call them at +1-713-462-1600.

Q: How do I find out if an item is instock or the Build time?

A: Please visit our updated instock inventory Here, it is updated often. Always reach out to us to verify if a product is instock or a quoted Build time at REDSTAREXHAUSTUSA@GMAIL.COM, 781-927-8491, or through the Chat.

Q: What is Inconel 625 and why should it be used in an exhaust system?

A: Inconel 625 is a nickel-based alloy that finds its application in exhaust systems due to its outstanding properties:

  1. Corrosion Resistance: Exhaust systems are exposed to corrosive elements like moisture and acidic gases. Inconel 625's excellent corrosion resistance ensures that the exhaust components can withstand these harsh conditions without deteriorating over time.

  2. High Temperature Strength: In exhaust systems, especially in high-performance or turbocharged engines, temperatures can reach extreme levels. Inconel 625 can maintain its strength and structural integrity at these elevated temperatures, reducing the risk of deformation or failure.

  3. Durability: Inconel 625's durability translates to a longer lifespan for exhaust components, which means less frequent replacements and maintenance.

  4. Reduced Weight: Its high strength-to-weight ratio allows for the construction of lightweight exhaust components. This can contribute to overall vehicle performance improvement by reducing weight.

  5. Thermal Fatigue Resistance: Exhaust systems undergo rapid heating and cooling cycles. Inconel 625's resistance to thermal fatigue helps prevent cracking and other forms of damage under these challenging conditions.

  6. Chemical Compatibility: Inconel 625 is highly resistant to a wide range of chemicals, making it suitable for handling the various substances present in exhaust gases.

In summary, Inconel 625 is chosen for exhaust systems in high-performance vehicles or other demanding applications because it ensures the exhaust system's reliability and longevity while maintaining optimal performance, even in harsh and high-temperature environments.

Q: What is Titanium and why should it be used in an exhaust system?

A: Titanium is a lightweight, strong, and corrosion-resistant metal known for its exceptional properties. It is used in exhaust systems for several reasons:

  1. Weight Reduction: Titanium is significantly lighter than traditional exhaust materials like steel. Using titanium components reduces the overall weight of the exhaust system and the vehicle. This can improve fuel efficiency, handling, and overall performance.

  2. High-Temperature Strength: Exhaust systems operate at high temperatures, especially in high-performance vehicles. Titanium can withstand these extreme temperatures without losing its strength, ensuring the exhaust components remain structurally sound.

  3. Corrosion Resistance: Titanium exhibits excellent corrosion resistance, making it ideal for withstanding the corrosive effects of exhaust gases, moisture, and road salts. This corrosion resistance helps prolong the lifespan of the exhaust system.

  4. Durability: Titanium is known for its long-term durability. It can resist wear and tear, ensuring the exhaust system lasts longer and requires fewer replacements.

  5. Improved Sound Quality: Titanium's unique acoustic properties can contribute to a distinct exhaust note. Many enthusiasts appreciate the unique sound produced by titanium exhaust systems.

  6. Aesthetic Appeal: Titanium has an attractive and distinctive appearance, often characterized by a blue or rainbow-like sheen when exposed to high temperatures. This makes it a choice for those who want a visually appealing exhaust system.

In summary, titanium is used in exhaust systems primarily for its weight-saving benefits, high-temperature strength, corrosion resistance, and overall durability. These characteristics make it an excellent choice for high-performance and sports cars, where lightweight materials and performance are paramount.

*If you would like to see more FAQ’s, please email us*