single or dual exhaust?

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62wild1

single or dual exhaust?

#1

Post by 62wild1 » Sun May 08, 2005 2:28 pm

Newbie question: I have been reading the post's and absorbing all the knowledge (trying)within these pages but don't recall seeing anything on exhaust so if I am redundant I apologise. I am new to the old school world and really enjoy the site. Well here it goes....

I purchased a 62 duo-glide and it has a single exhaust and I would like to put a dual setup on it. I see there is a dual, and a dual with crossover. Is there a noticable power gain with the dual setup and which one is recommended? I also wonder about the straight fishtails or going with the baffeled sets. Is there also a recommended company for quality pipes?

Thanks for any help in advance



Cotten
Posts: 6788
Joined: Mon Aug 26, 2002 9:09 am
Location: Central Illinois

#2

Post by Cotten » Sun May 08, 2005 4:25 pm

Do you know of a source of repop "true duals" that are anything like "correct"? Paughcos are one-size-fits-none, and the chrome ain't what she used to be. (Not her fault!)

If you choose the dual 'crossover' system, I suggest that you silversolder a freezeplug into the very bottom of the rear header pipe, where it inserts into the Y pipe, thus truly separating the front and rear.

Anything that adds that much weight to a machine cannot improve performance!
Fishtails are cute, but they mess up the reversion signal that telegraphs back up the pipe to the port. Straights make it worse. Their sound is great,.. if you like obnoxious.

I suggest inspecting generic repops from Tedd, as I was once told they were made by Dennis Corso.

chucktx
Posts: 34
Joined: Sat Jan 22, 2005 9:16 am
Location: texas

#3

Post by chucktx » Mon May 09, 2005 3:11 am

hi cotton....what is this"reversion signal that telegraphs back up the pipe to the port" you speak about??? i have never heard of this before.
chucktx

Guest

#4

Post by Guest » Mon May 09, 2005 8:07 am

Hi Cotten, the only duel setups I have seen is what I get off pictures on the net and what I have seen in the parts books. I ordered the palmer book on restorations but being in the big sand box it is going to take a bit.

I have not looked into Tedds yet but it will be my next stop. I see no reason to clutter the bike with a crossover then if it has to be plugged anyway. I have straights (Longshots)on my Wide glide and had it Dyno'd and it performed better without the baffles and also has less vibration without them, can't figure that one out yet. Was told even just putting a bolt through the end of the pipe makes an improvement???

FYI my Word auto correct kept changing your name on my email's, thought I was loosing it for a bit.

Thanks for the help!

Cotten
Posts: 6788
Joined: Mon Aug 26, 2002 9:09 am
Location: Central Illinois

#5

Post by Cotten » Mon May 09, 2005 12:26 pm

Exhaust tuning is a study in itself, and I can only suggest a websearch for discussions on reversion, which is the tendency of each pulse to bounce back up the pipe. An ideal system uses the chain of pulses to pull the next one out faster, whereas a poor system is hindered by the echo of the reversion.

Expansion chambers, baffles, or even an obstructing bolt can disrupt the returning signal. The term "backpressure" is often incorrectly assigned to this phenomena. (Megaphones were often correctly called 'echo cans'.)

The rear header's exit to the Y doesn't have to be plugged, but removing one that had been installed into a friend's '65 changed it enough that he put it back.

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