Modifying Mac' One-Piece Mufflers
01-03-2004, 10:00 AM
#1
Modifying Mac' One-Piece Mufflers
I have several of these still in original condition other than having been used. I'm wondering if they are simply a muffler or are they 'tuned' any to improve run characteristics? What I'm really wanting to know...is it OK to drill out the tailpipe a tad? I like an exhaust pipe ID to be the same as the net opening on the carb...if not just a little bit bigger on the exhaust pipe. Yes, this does make the engine run a bit louder, but it typically picks up a few hundred RPM, too. Well, what do you think?
01-03-2004, 12:02 PM
#2
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RE: Modifying Mac' One-Piece Mufflers
I read in the past of someone who was drilling them out and getting more revs, possibly someone in combat. Being highly tuned does not seem to be the reason for their popularity. Rather, they are light and sturdy alternatives to the standard mufflers that tend to come apart and loose pieces. On the other hand, I think some folks do report a couple hundred rpm increase over stock mufflers.
Ernie
Ernie
01-03-2004, 12:35 PM
#3
Senior Member
RE: Modifying Mac' One-Piece Mufflers
Gene,
The Mac's one-piece muffler's only advantage over the stock silencer, that came with the engine, is its weight (and size).
It is not "tuned" in any way, nor does it have any added expansion volume, or a large outlet, that may potentially boost the engine's power.
To make matters worse, it now carries a prohibitively high purchase cost, that only American modelers (and wishful believers elsewhere) are willing to shell out, given its very few advantages. As if $38-$43 is peanuts for anyone.
If you want some added power, the Tower/Hobbico .46 muffler can do it for you, and if you want even more power, the very expensive Jettstream, or Ultrathrust, or other true tuned exhaust systems.
If you want more power for nothing, drill out the exit hole size of your muffler, or for a few bucks, extend the expansion chamber of your stock silencer. It will help more and will not cost you nearly as much, as the Mac's one-piece.
The Mac's one-piece muffler's only advantage over the stock silencer, that came with the engine, is its weight (and size).
It is not "tuned" in any way, nor does it have any added expansion volume, or a large outlet, that may potentially boost the engine's power.
To make matters worse, it now carries a prohibitively high purchase cost, that only American modelers (and wishful believers elsewhere) are willing to shell out, given its very few advantages. As if $38-$43 is peanuts for anyone.
If you want some added power, the Tower/Hobbico .46 muffler can do it for you, and if you want even more power, the very expensive Jettstream, or Ultrathrust, or other true tuned exhaust systems.
If you want more power for nothing, drill out the exit hole size of your muffler, or for a few bucks, extend the expansion chamber of your stock silencer. It will help more and will not cost you nearly as much, as the Mac's one-piece.
01-03-2004, 12:51 PM
#4
RE: Modifying Mac' One-Piece Mufflers
I've bought several for .25's & .36's that were used at very good prices and currently have two more for a .46 on order from Quantum...I paid $29 each for them. I like them because they are one-piece, look nice, are streamlined and light. It appears that drilling the tailpipe out will improve the top end and result in no side effects.
Personally, I think the Tower .46 muffler is over-rated as I have seen the same RPM's out of a TT PRO .46 muffler with the baffle removed and the tailpipe bored-out. The TT muffler is also quieter and smaller...possibly lighter, too.
If I want even more performance I simply make a mousse can pipe...those DO work quite well and are typically lighter than a stock muffler when built the way I build them. I'm going to post a thread on my method when I get the header for one I'm going to make for a TT GP .15. The thread will have pictures of each step of construction. It ends up making a nice looking, light muffler that gets a LOT more out of an engine than a stock muffler will...even with the baffle removed and tailpipe bored-out.
Personally, I think the Tower .46 muffler is over-rated as I have seen the same RPM's out of a TT PRO .46 muffler with the baffle removed and the tailpipe bored-out. The TT muffler is also quieter and smaller...possibly lighter, too.
If I want even more performance I simply make a mousse can pipe...those DO work quite well and are typically lighter than a stock muffler when built the way I build them. I'm going to post a thread on my method when I get the header for one I'm going to make for a TT GP .15. The thread will have pictures of each step of construction. It ends up making a nice looking, light muffler that gets a LOT more out of an engine than a stock muffler will...even with the baffle removed and tailpipe bored-out.
