If you live anywhere near Houston, you need to make a pact with The Devil to gain access to one of the best custom shops around, namely Lucky Devil Metal Works. After you fork over your soul, Mr. Devil will grant your wishes. That’s why our friend Manny was happy to get a call from Mr. Devil asking if he’d like a set of D&D Fat Cat pipes for his new 2006 Dyna Street Bob. Manny had already installed H-D Screamin’ Eagle slip-on mufflers and high-flow air filter, but the opportunity to add a set of D&D Fat Cats was too good to turn down. So good in fact, that he rode through Houston rain and flooded streets to reach The Devil’s Den.

About Dyna Pipes

Each pipe is encased in a full wrap heat shield that keeps all discoloration from view. D&D manufacturers the premium exhaust line from only the highest quality materials with each pipe given a show-chrome finish.

The 2-into-1 pipes are torture tested on D&D's state-of- the-art in-house Super Flow Eddy Current Ram Air dynamometer. This is done in combination with the Super Flow Bench and the first in the industry, multi cylinder Lambda Fuel Air Ratio Sensors, which are interfaced with the Dyno for real time meter and graph analysis. Each pipe is dyno tuned for maximum performance and sound.

D&D 2-into-1 Fat Cats have been around for sometime and are known for their performance, looks, sound, and quality. We could tell by just handling the pieces as we unpacked them that this set would more than live up to expectations. The good news here is that D&D designed these cats specifically for the 2006 EFI configuration and a SE air filter. They even provide a new SE Race Tuner map number. That’ll be the next thing on Manny’s list.

The set comes ready to install:
--Both O2 sensor bungs fit the stock sensors without modification. Mounting flanges are pre-installed, no C clips required.
--Heat shields are pre-installed.
--New gaskets are included.
--The new mounting bracket bolts to the transmission case the same as the OEM bracket.

It’s basically, take off the old set, unpack, and install…

Yeah, that’s one of them little O2 buggers, get used to ‘em.

The required “before installation” photo.

Mr. Devil helped take off the OEM exhaust. Start by removing the seat and factory heat shields. Disconnect the O2 sensor plugs. Use a 1/2 socket to remove the nuts on the header studs. A wiggle socket or flex extension here will help because the O2 sensors partially block access. Next use the same 1/2 socket to remove the factory bracket from the transmission case. Now use a 9/16 socket to loosened the clamp next to the foot peg. The stock pipes come off easily as a unit.

Manny transfered the stock O2 sensors from the OEM pipes to the new Fat Cats. Use a small amount of anti-seize on the sensor threads but be careful not to get any on the sensor. It’s a $10,000 EPA fine if they don’t work! Not really, but if the sensors don’t work, the EFI module won’t work either.

To begin, on the new Fat Cats, install the hefty D&D mounting bracket onto the transmission case. It’s a quality fit and a solid part.

Mr. Devil has left the building, leaving Manny to finish the install. Hang the pipes by slipping the header flanges over their studs. Loosely tighten the header nuts. Then install the factory clamp and bolt next to the foot peg. Finally screw in the new bolts through the bracket to the new muffler. Check to see if the pipes are straight. Rattle the pipes while finger tightening all the nuts and bolts. When satisfied, tighten (ok, torque to spec) the header nuts first, rear bolts, and muffler clamp.

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