Kooks R35-35-10 3.5 in. Round Stafford Spec Muffler 10 in. Body T304 Stainless Steel

Stafford Spec 3.5 Inch Round Stainless Muffler Engineered for Racing Exhaust Standards

The R35-35-10 is a 3.5 inch Stafford spec round weld on muffler with a 10 inch body, constructed from T304 stainless steel to meet the specific requirements of Stafford Speedway class rules and similar short track racing regulations. Stafford spec muffler standards define a minimum noise attenuation threshold that keeps racecars compliant at venues with sound limits while still allowing the exhaust flow necessary to compete at the front of the field. This muffler is designed to meet those specifications without strangling the engine, making it the correct choice when you need a tech legal muffler that does not give up performance unnecessarily.

At 3.5 inches through and 10 inches of body length, the R35-35-10 flows generously for the pipe diameter, and T304 stainless construction handles the repeated high heat cycling of racing use without deteriorating. For circle track racers, drag racers, and road course competitors building to rulebooks that reference Stafford spec muffler standards, or for any builder who wants a 3.5 inch stainless weld on muffler in a short compact body, this muffler delivers a purpose built solution from a manufacturer with a deep history in performance exhaust engineering.

Key Features

• 3.5 inch inlet and outlet for maximum flow in 3.5 inch exhaust systems
• 10 inch body length in a compact Stafford spec round configuration
• Designed to meet Stafford Speedway and similar short track racing sound regulations
• T304 stainless steel construction for durability in racing and high performance applications
• Weld on installation for a permanent, secure exhaust connection
• Universal fitment for racecars and high performance street builds on 3.5 inch systems

What's Included

• 1 x this muffler 3.5 inch Stafford spec round weld on muffler with 10 inch body

Specifications

Frequently Asked Questions

What does Stafford spec mean for a muffler?
Stafford spec refers to a muffler specification established by Stafford Speedway in Connecticut that defines a minimum level of sound attenuation for racecars competing at that venue. Other tracks and sanctioning bodies reference similar standards. A Stafford spec muffler must meet the required noise reduction threshold to pass tech inspection at compliant events.

What pipe size does this muffler require?
This muffler has a 3.5 inch inlet and 3.5 inch outlet, designed for installation into 3.5 inch exhaust tubing via weld on connections.

Is this muffler only for racing applications?
No. While it is designed to meet Stafford spec racing sound requirements, this muffler can be used in any 3.5 inch performance street or track exhaust application where a compact 10 inch round muffler is preferred.

Will this muffler pass tech at any track?
This muffler is designed to meet Stafford spec requirements. Whether it passes tech at a specific track depends on that track's muffler regulations. Always verify your track's specific rules before purchasing.

How is this muffler installed?
This muffler is welded into the exhaust system. Both inlet and outlet connections are welded to adjacent 3.5 inch exhaust tubing for a permanent installation.

What material is this muffler constructed from?
T304 stainless steel, providing corrosion resistance, high temperature strength, and long service life in racing and street performance applications.

How loud is this muffler compared to a standard street muffler?
This muffler meets a defined spec for racing noise reduction. It is designed to pass track tech while maintaining performance flow, so it will be louder than a typical street muffler but quieter than an open or straight pipe exhaust.

Can I use this muffler on a street vehicle?
Yes. The muffler provides sound attenuation appropriate for performance street use at the 3.5 inch pipe diameter, though it is likely louder than what a noise ordinance would permit on a street legal vehicle in many jurisdictions.

Is this muffler sold individually?
Yes. This muffler is sold as a single unit.

Does the inlet and outlet measure 3.5 inches inside diameter or outside diameter?
Exhaust muffler and pipe sizing conventions in the aftermarket typically refer to the nominal outside diameter of the pipe being connected. Confirm the pipe OD of your exhaust tubing matches 3.5 inch nominal before ordering.

Installation Instructions

1. Confirm track or series rulebook approval for this muffler before beginning installation.
2. With the exhaust system cool, determine the muffler position in the exhaust path.
3. Cut the 3.5 inch exhaust tubing at the inlet and outlet positions with proper allowance for weld joints.
4. Insert this muffler with the inlet toward the engine.
5. Verify clearance to chassis components, body panels, and the floor at the muffler body position.
6. Tack weld to confirm alignment before completing full circumference welds at both connections.
7. Use T304 compatible welding filler for strong, corrosion resistant joints.
8. Inspect welds and verify exhaust system integrity before the next event.

Prop 65 Warning

WARNING: This product can expose you to chemicals including Chromium and Nickel, which are known to the State of California to cause cancer, birth defects or reproductive harm. For more information go to www.P65Warnings.ca.gov.