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Thunderheader Racing Products 2 into 1 High Performance Long Style Exhaust System - 1054

  • Part #: 251458
  • Manufacturer Part #: 1054
This item is no longer available

Overview of Thunderheader Racing Products 2 into 1 High Performance Long Style Exhaust System - 1054

  • ThunderHeader head pipes have been tuned to the proper length and diameter to produce maximum horsepower and a excellent torque curve
  • A patented collector is used
  • The collector is designed to direct spent gases through four acoustical dampening chambers
  • The flow director serves a multi-task function: directs outgoing flow through four acoustical dampening chambers creating a spiral motion upon exiting to atmosphere and it also forms a pyramidal shaped anti-revision trap to minimize the amount of air rushing in
  • In conjunction with the flow director, a diffuser shroud is attached to the reverse cone, this patented device is designed to defuse the air rushing in as the pressure inside of the system becomes equal to atmosphere

Included Items:
(1) Exhaust Header
(2) 5/16-24 x 3/4 Hex Bolts
(6) 5/16 Plain Washers
(1) 5/16 Lock Washer
(1) 5/16-18 Nut
(2) 5/16-24 Lock Nut
(1) Mounting Bracket
(1) 5/16-18 x 1 Hex Bolt
(1) Clamp 3/4
(1) Clamp 5/8
(1) Collector

NOTE: This is a 2 into 1 long style (right side only)

Not all products are legal for sale or use on pollution controlled vehicles. Check your local laws and the manufacturers information

There is no warranty on exhaust pipes and mufflers with regard to any discoloration. Discoloration (bluing) is the result of tuning characteristics, cam timing, carburetor jetting, overheating, etc., and is not caused by defective manufacturing. See the CHEMS/LUBES section for products that will help prevent or remove bluing.

Installation of a new exhaust system may change your motorcycles fuel-air mixture requirements. Please consult the exhaust manufacturer directly with questions regarding any modifications that may need to be made during, or after, installing their product. If a jet kit or fuel processor is recommended, see the FUEL/INTAKE section

Specs for Thunderheader Racing Products 2 into 1 High Performance Long Style Exhaust System - 1054

Finish Chrome
Style - Exhaust Tip Tapered Tip
Type - Exhaust 2-Into-1 System
Units Each
Weight 19.25 lbs

Specs for Thunderheader Racing Products 2 into 1 High Performance Long Style Exhaust System - 1054

Finish Chrome
Style - Exhaust Tip Tapered Tip
Type - Exhaust 2-Into-1 System
Units Each
Weight 19.25 lbs

Fitment for Thunderheader Racing Products 2 into 1 High Performance Long Style Exhaust System - 1054

See if this part fits your ride

Part 251458 fits the following machines

Harley-Davidson
  • 2008 Harley-Davidson Electra Glide Classic (EFI) - FLHTC
  • 2007 Harley-Davidson Electra Glide Classic (EFI) - FLHTC
  • 2008 Harley-Davidson Electra Glide Standard (EFI) - FLHT
  • 2007 Harley-Davidson Electra Glide Standard (EFI) - FLHT
  • 2008 Harley-Davidson Electra Glide Ultra Classic (EFI) - FLHTCU
  • 2007 Harley-Davidson Electra Glide Ultra Classic (EFI) - FLHTCU
  • 2008 Harley-Davidson Road Glide (EFI) - FLTR
  • 2007 Harley-Davidson Road Glide (EFI) - FLTR
  • 2008 Harley-Davidson Road King (EFI) - FLHR
  • 2007 Harley-Davidson Road King (EFI) - FLHR
  • 2008 Harley-Davidson Road King Classic (EFI) - FLHRC
  • 2007 Harley-Davidson Road King Classic (EFI) - FLHRC
  • 2007 Harley-Davidson Road King Custom (EFI) - FLHRS
  • 2008 Harley-Davidson Street Glide (EFI) - FLHX
  • 2007 Harley-Davidson Street Glide (EFI) - FLHX
4.3 / 5.0
12 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
7
4
0
0
1
Finish
4.7 / 5
Performance
4.9 / 5
Finish
4 / 5
Performance
5 / 5
instant horsepower
best addition to my motor yet..horsepower increase you can feel in the seat of your pants ...product was expertly packaged and arrived in perfect condition .....
January 18, 2011
Finish
5 / 5
Performance
5 / 5
The right pipe-apology long review
The right sound, easy to install, 10HP, 20FtLbs Torque bolt-on. Get the shield kit or cook your leg.
Yes it's a bit louder than VH duals. But a deeper, respectful, commanding duntDunt. Not the obnoxious blatBlat from the BigRadius 2-1.
So I got a free Dynotune from a dealer, who dyno'd it the next week with only this $650 mod (with shields). From 94HP/104# torque to 104hp/124#torque.
Provides the performance I needed from stock on my '09 FXDFSE. Dynotune is a must from stock-it turned my skoot to a monster.
Buy 2 rear tires, cause they won't last.
Comes with O2 ports, perfect fitment, mounting bracket and all you need minus the head port gasket (why not? -it's right there and $5 pair).
25 mins to install, no fancy tools except a swivel socket extension. And ale-pale Ale.
January 28, 2014
Finish
4 / 5
Performance
5 / 5
No Review Title Entered By User
Need longer bolts to mount bracket to transmission
Tight fit between pipe and foot-board - slotted hole would be helpful
January 19, 2011
Finish
5 / 5
Performance
5 / 5
Great addition
I recently purchased a 2001 Dyna Low rider with 7000 miles from a great previous owner that did very little to the bike but maintain it. He did put a Mikuni carb on it. My plan was to do the bike up right and quick..two weeks...but tasteful. I added the intake and cleaner and quite a few other items to dress the bike up to my style. Most importantly I waited until last to do the exhaust, so I called Mikuni and talked to Steve...told him what I was doing and asked for his advice. Afterwards, given my style I was going for and the performance I was seeking, he offered the Thunderheader as a choice. He explained that since I lowered the bike and wanted performance, this was a good choice. I forgot to mention, this is my first bike, and I did all the work and upgrading myself. This pipe couldn't have fit better and easier. Awesome piece of equipment!
July 11, 2013
Finish
4 / 5
Performance
5 / 5
wanna make your bike sound like a drag bike?
very good investment for the price. It is only loud when you really twist the wick. Really increased the torque curve.At 65 or above you will really feel the push all the way up to where you think you are going to take off.At 120 you still can feel the torque pushing you back.
January 25, 2012
Finish
5 / 5
Performance
5 / 5
Thunderheader Exhaust
Love the way this exhaust sounds on my fatboy. My husband has one on his roadking and we are very impressed!
January 6, 2012
Finish
5 / 5
Performance
5 / 5
No Review Title Entered By User
No Review Text Entered By User
May 18, 2010
Finish
5 / 5
Performance
5 / 5
Rumble
Just what I had heard, great sound and looks great. Fast shipping and great communication
December 5, 2015
Finish
5 / 5
Performance
5 / 5
Great Pipes
Looks ands sounds great. It is bolt on horsepower for sure.
October 23, 2012
Finish
5 / 5
Performance
4 / 5
No Review Title Entered By User
One of the easiest pipes I've installed. (and I've installed many) It has that one and only thunderheader sound. Very good finish, I would recommend to others.
February 28, 2012

Instructions and Manuals for Thunderheader Racing Products 2 into 1 High Performance Long Style Exhaust System - 1054

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