2 into 1 Exhaust Collector Systems

2-into-1 Exhaust Systems for Circle Track Race Cars

The Ultimate Exhaust System for Your Race Car

Let’s face it: Exhaust systems are a drag to install on a race car.  For this reason, most racers take the easy way out and simply hang a couple of pipes on the manifolds.  This is the worst way to run an exhaust system with cast iron manifold!

Installing an exhaust system where the two exhaust pipes run into our 2-into-1 collector will produce more power and make it quieter than dual pipe systems.

This original Brzezinski Racing Products design routes the exhaust pipes from each side of the engine into one common collector. With this design we are tricking the engine into thinking it is firing every 90 degrees as opposed to the random firing of dual outlet systems.

2-into-1 systems have a dramatic effect on power from 3500 to 7000 rpm. The most important fact to remember when building your system is that the primary pipes need not be routed in any particular way to gain the added horsepower of the 2-into-1 effect.  While “over the top” installation is generally easier, a system underneath the car will achieve the same power figures. The engine doesn’t care how the exhaust pipes are routed. However, NOT running your two exhaust pipes into one of our collectors will cost you 10 to 25 horsepower!

Corvette Manifold 2-into-1 Dyno Test

As you can see in the dyno test results in the dyno chart at right, there is a 29 hp gain at 5000 rpm with the addition of a 2-into-1 System.

Corvette Manifold 2-into-1 dyno

2-into-1 Exhaust System Kits

  • Quieter than dual systems
  • 10 to 25 more horsepower than dual pipes
  • If you need additional pipes, we have them in stock
  • Any unused pipes from the 2-into-1 kits can be returned for full credit.


Part# 2-into-1 Exhaust Systems  Price
171A-3.5 2 1/2″ Exhaust System Kit for 2 1/2″ outlet Corvette Ram Horn manifolds.  Kit includes: (1)#164A kit, (1)#169B Collector, (5)#167A 90° pipes &  (1)#168A 45° pipe.

171A-193 2 1/2″ Exhaust System Kit for Log Manifolds.
 Includes:(2)#193F-25A Gasket-Less adapters, (1)#169B collector, (3)#167A 90° pipes and (3)#168A 45° pipes.

The key component of the 2-into-1 System

We have run countless dyno tests on 2-into-1 versus dual pipe systems. Whenever the primary pipes are routed into one of our collectors, 10 to 25 horsepower is gained.


Part # Description Price
169 Collector, 3″ inlets and 3 1/2″ outlet for 2 barrel engines. $140.00
169B Collector, 2 1/2″ inlets and 3 1/2″ outlet. 140.00
170 Collector, 3″ inlets and 4″ outlet for 355 and larger 2 barrel engines running good manifolds or 4 barrel engines. 140.00
Tips for Building your 2-into-1 System . . .

  1. Optimum Primary Pipe Length — Keep the primary pipes as short as possible. Systems are designed around individual 90° and 45° bends, which are 12″ long. Do not use more than 72″ of pipe on each side. This translates into a maximum of 6 pipes per side. Three horsepower will be lost for each additional 12″ section beyond 72″. These recommendations are based on dyno tests with stock and modified Corvette, Chevy II and Log manifolds.
  2. Unequal Length Primary Pipes are OK — Our dyno tests have concluded that variations in primary length have no adverse effect on power when a collector is used. Primary pipes which are equal in length, or as close as possible, are preferred, but in some applications this is just not possible. So, if your pipes going into the collector are not equal, don’t worry.
  3. Pipe Length for Dual Pipe System — If you are restricted to a dual pipe system, pipes should be 45″ to 55″ in length, equal on each side, and run a balance tube the same diameter as the exhaust pipe.
  4. Secondary Pipe Length — Run a minimum of 12″ of secondary pipe after the collector. Adding more length has little effect on power. In other words, “We’ve run 1 to 6 feet of secondary pipe and noticed absolutely no power difference.”
2-into-1 Instructions
including TIPS
for Building your
2-into-1 System
(46K pdf file)

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