FMF Powerbomb to stock 08 Muffler


27 replies to this topic
  • grayracer513

Posted October 29, 2009 - 03:40 PM

#21

Can you honestly say that the FMF power Bomb will 100% be the best solution here? What would you do with your money?

That wasn't really the question, was it? Only a matter of whether it will or won't fit. But then you raised the question of power output when you said:

...why down grade?

...which asserts that a PowerBomb is factually inferior in some way to the stock '08 header, an assertion for which you offer no support. You do mention that you have run the '08 muffler with a PMB cap, and that should remove the second, more restrictive, of the two cones in the core, and evidently, you were happy with the improvement. I'm not surprised. But, you fail to note whether you have run any other header with that setup, so from your experience, at least as presented, we can't tell whether a different header will accomplish one thing or any other.

My experience with PowerBombs has been that in spite of any claims to the contrary, they don't really add a significant amount of power at peak, but rather, they have the tendency to flatten the torque curve and broaden it because the engine "sees" them as a header without a particular fixed length. They are very effective on engines with a pronounced "hit", as they work to smooth that out by spreading the power downward from that point in the power band. So given the OP's remark/complaint regarding the bike now behaving like a two stroke, I'd have to guess from experience that it would be helpful. Then again, so might a stock '07 header, for different reasons.

The statement you made regarding header volume:

if you want a lower volume header get a stock 07.

...carries the implication that a larger volume header is categorically better than a smaller one. This is simply not true, as I already pointed out. One of the reasons Honda started using double walled pipe so long ago was because American buyers would refuse to accept the bike with headers on them that were the actual, optimal size for the engine.

As far as the point at which one could consider the modified '08 muffler non-restrictive, I'd have to say that would be when both cones were removed, and the core was equal to the equivalent area of both exhaust valves, or 1.5" in this case. That's a bit arbitrary, and is dependent on several things that we haven't discussed. Nevertheless, with the removal of the rear cone, the muffler has certainly become less restrictive than it was, and one should be able to move toward a more nominal header size than the oversized '08 model.

Would I do it? Within my current budget, no, unless I could buy one used, and I might experiment with an '06 or '07 header first. If I had more disposable income, I probably would though, but not to get more power; to get more usable power over a wider range.

  • Demo_Slug

Posted October 29, 2009 - 04:18 PM

#22

[COLOR=black]"why, downgrade". stock is TI. power bomb is steel. the word power is no where in my post that is all you big guy. putting words in my mouth.[/COLOR]

[COLOR=black]"if you want a lower volume header get a stock 07." this carries no connotation other then it is a smaller header, once again the rest is all you. I agree with what you say but has nothing to do with the "lesson" you are try to teach me or the "example" you are trying to set.[/COLOR]

[COLOR=black]And you even admit that an 07 is worth a try. And what you would do . [/COLOR]

[COLOR=black]I just don’t get the very rude post you made about my post. You read way to much into, stopped just short of calling me an idiot. [/COLOR]

[COLOR=black]in the end you reminded me why I really don’t post here anymore. [/COLOR]

[COLOR=black]good day sir. [/COLOR]

  • KJ790

Posted October 29, 2009 - 04:53 PM

#23

[COLOR=black]"why, downgrade". stock is TI. power bomb is steel.[/COLOR][COLOR=black][/COLOR]


You can get the powerbomb in either titanium or stainless steel. The weight difference is mere ounces, but the stainless header is much more durable than the stock header. I wouldn't call a stainless header a downgrade due to the material, they are much more durable than titanium headers due to the thickness difference.

  • grayracer513

Posted October 29, 2009 - 07:03 PM

#24

I wouldn't call a stainless header a downgrade due to the material, they are much more durable than titanium headers due to the thickness difference.

There been a number of times, in fact, that people decided not to buy FMF MegaBombs because they were not produced in stainless. The Ti version is an expensive piece to put on an off-road ride just to bash a dent in it. Plus a lot of people don't see the few ounces Ti saves to be an advantage worth doubling the price for. A lot of off-roaders consider stainless an upgrade.

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  • COV225

Posted October 30, 2009 - 06:23 AM

#25

Alright put the boxing gloves down guys. Thanks for answering my question. I think Im just going to put a TTR125 header on it!....just kidding. Ill just work on twisting the throttle sooner/longer and get new tires.

  • dicky580

Posted October 30, 2009 - 01:30 PM

#26

It does fit. I put the power bomb on my 08. FMF also says somewere on the website that there header pipes are interchangable with other exhauasts. Which is also true cause im running the power bomb header with a vance and hines slip on. Kinda ghetto but its a full system for less than 450 bucks. The gains from the header were impressive, the motor revs up much faster and has a better feel to the power in general. Id say toss it on. for the cost its a good upgrade

  • COV225

Posted November 02, 2009 - 11:39 AM

#27

Awesome thanks for the help. Ill gonna order one today.

  • Sprew

Posted November 02, 2009 - 05:34 PM

#28

... and that should remove the second, more restrictive, of the two cones in the core,


I'd have to say that would be when both cones were removed, and the core was equal to the equivalent area of both exhaust valves, or 1.5" in this case.


curious how you arrived at these two conclusions.





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