Author Topic: Duel exhaust  (Read 4492 times)

Offline OneLapper

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Re: Duel exhaust
« Reply #15 on: May 08, 2010, 02:00:32 PM »
I have run thousands of miles with a straight through, no muffler 5" pipe on my 8V71N.  Way too loud!!!!!  Painfully loud, but very noticeable gain in HP.

1964 PD4106-2853

Offline buswarrior

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Re: Duel exhaust
« Reply #16 on: May 08, 2010, 02:40:21 PM »
Beware, most all of the videos of running engines without mufflers are on idle and free wheeling with no load.

And the camera does a good job of making it difficult to gauge the true noise level.

Way different from what noise will come out at full throttle on the road.

You can only barely get a blip of REAL noise by goosing the throttle, the governor backs the fuel rack off almost as soon as it opened, as it spins up to speed too rapidly for you to get the full effect.

Just so long as you do a little experimenting before committing dollar$ to an unexpected ugly baby...

happy coaching!

Frozen North, Greater Toronto Area

Offline Rick 74 MC-8

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Re: Duel exhaust
« Reply #17 on: May 08, 2010, 03:03:48 PM »
For the time being I think I'm just going to repair the 5" 90 going into the muffler and see if I can in large the 4.5" muffler outlet.  We have a trip planed for June. I can check mpg and performance and decide if I want to take things further I know I don't want straight pipes.

                                                                         Rick 74 MC-8
About 20 Miles West Of Chicago

Offline JohnEd

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Re: Duel exhaust
« Reply #18 on: May 08, 2010, 05:11:13 PM »

I was parked next to a MCI9 years ago.  Never saw the owner in the three days that we were neighbors.  I peered in the screen on the passenger side and could only tell that it looked like a 8V92.  It was a DD though.  He must have aired up using his genny and run his block heaters in prep for starting and making a fast getaway.  He fired off at 8 AM and I was knocked from my bed in an ignominious pile on the floor.  It was a straight pipe,,,must have been...and, HOLY CRAP BATMAN!!!!  But he lit her off and pulled out in the same instant and if I made that much noise I would beat a hasty retreat,as well.  Maybe he was a real little guy without a gun and was tired of being beat upon. Who knows but had I been within arms reach....well that is another fiction.  It had duals o it cause one ex pipe came out the passenger side where I was sleeping before my heart attack.

Still more power is a really attractive thing.

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Offline NewbeeMC9

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Re: Duel exhaust
« Reply #19 on: May 09, 2010, 08:07:37 AM »

My Stock Tailpipe was damaged when I bought my bus, looked like it had been backed into a curb.  I took it off and bought a 5" Chrome tip at the truck place with a slight 900 exit.  I had some pieces of steel and made spacers to bolt/clamp it to the muffler extension.  Made a noticeable improvement in fuel use over the crumpled one ;).

I do think I need to clock it at about 450 to the outside so I can observe smoke in the mirror better.
It's all fun and games til someone gets hurt. ;)

Offline JackConrad

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Re: Duel exhaust
« Reply #20 on: May 09, 2010, 11:26:51 AM »
I do think I need to clock it at about 450 to the outside so I can observe smoke in the mirror better.

That will also help prevent stirring up as much of a dust/leaf cloud when driving "off road"  Jack
Growing Older Is Mandatory, Growing Up Is Optional
Arcadia, Florida, When we are home

Offline Chopper Scott

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Re: Duel exhaust
« Reply #21 on: May 09, 2010, 01:29:34 PM »
My muffler was shot so I built a 5" J pipe to replace it and came off of it with a Borla 4" ss straight through muffler designed for racing. I exited it out the side at an angle so I could see the exhaust in the mirror much as the original exit was. It's still pretty loud. Generally by the time I get up and moving around it's time for the neighbors to get up anyways! :D One thing good about it is nobody sits on my left rear for long when we're rolling down the interstate!
Seven Heaven.... I pray a lot every time I head down the road!!
Bad decisions make good stories.