Killer B Motorsport 4-1 Holy Header 2-Bolt - 02-14 WRX / 04-21 STI

Killer B  are pure artists in metal fabrication, and they have a large catalog with a wide variety of performance enhancing, oiling, fabrication components, along with accessories for your interior, exterior, or your engine bay. 

Here you are looking at the Killer B Motorsport 321 Stainless Steel Holy Header. This particular header will come with the 2-bolt up pipe option, and it will also come equipped with an EGT sensor bung. This header is a great option for those of you looking to improve the sound and power throughout the entire RPM range. 

Here are some key features:

• Cast Collector: The collector is made of thick walled cast 347 stainless. This design removes several welds which removes flow disruption for less turbulence. This also allows the collector to be designed as a true high-velocity merge.
• Short Equal Length Primaries: Shorter length primaries make for an equal length header which means less header volume and quick spool up. 
• Symmetrical Primary Design: A similar tube length and bend geometry keeps the pulse velocities high and consistent when compared to equal length headers with different non-symmetrical primary tubing geometry.
• Smooth Mandrel Bends: All the bends utilize a mandrel to promote non-restrictive flow, and Killer B uses the largest bends possible at every location. 
• Thick Walled 321 Stainless Steel Construction for Long Life: 321 is alloyed with titanium which not only costs more but it is ideal to handle the elements of extreme heat found in the turbocharger. With that being said, the turbocharger will create heat that will surpass the limits of 304 stainless steel, and 321 is more robust to promote longer life. 
• 2-Bolt Up Pipe Connection allows for connection of 2-bolt flange style up-pipe connection
• Weighs 17lbs
• Works with OEM EJ25 oil pans along with the Killer B Motorsport Performance Aluminum Oil Pan
• Made in the USA