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Discussion Starter · #1 ·
I have a 302 Ford in a 1950 Dodge pickup. The guy who put the exhaust on put two 90 degree turns on the left exhaust pipe in order to clear the original gas tank. The engine has a vibration and I have checked everything I can think of - the exhaust bends seem to be the issue to me. Plus the bends are right under the drivers feet and I have to listen to the damn noise, like there isn't enough of that. Anyone have suggestions?
 

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I have a 302 Ford in a 1950 Dodge pickup. The guy who put the exhaust on put two 90 degree turns on the left exhaust pipe in order to clear the original gas tank. The engine has a vibration and I have checked everything I can think of - the exhaust bends seem to be the issue to me. Plus the bends are right under the drivers feet and I have to listen to the damn noise, like there isn't enough of that. Anyone have suggestions?
Find something else to worry about. 2 90 degree bends aren't a problem for a street car.
 

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Obvious question for me is, can the exhaust be done without the 90 turns? If so, then take it bck and ask him to remove them and put some gradual turns in.
I doubt it's causing a vibration in the motor, but it still needs to be fixed if possible. The exhaust should match side to side as much as possible.
 

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The work was done 10 years ago and the guy is long gone. I have owned this truck for 30 years and mostly just kept it running so I could go to the dump. The exhaust could be massaged to eliminate the 90s, but I would have to replace the gas tank to make the pipes match as the original engine was a flat-head 6 - exhaust all on the passenger side. There is not a whole lot of room for the left side. Everyone tells me that it can't be the exhaust but the restriction (back pressure) from those bends just seems so wrong.
 

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The work was done 10 years ago and the guy is long gone. I have owned this truck for 30 years and mostly just kept it running so I could go to the dump. The exhaust could be massaged to eliminate the 90s, but I would have to replace the gas tank to make the pipes match as the original engine was a flat-head 6 - exhaust all on the passenger side. There is not a whole lot of room for the left side. Everyone tells me that it can't be the exhaust but the restriction (back pressure) from those bends just seems so wrong.
Are they crimpled bends? No one uses those any more but they may have 10 years ago. If so just replace them with a decent set of bends.

If you're that hung up on it just have the two sides joined with a y and run a single exhaust. On the side with room.
 

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Discussion Starter · #6 ·
It is a single exhaust. The filler pipe for the gas tank is right behind the seat so that is how close the tank is. I think I will have someone replace the bends (not crimped now) with more expansive turns. Maybe then I won't have to listen to the growl of the exhaust. Then again, I can turn up the radio and go deaf.
 

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It is a single exhaust. The filler pipe for the gas tank is right behind the seat so that is how close the tank is. I think I will have someone replace the bends (not crimped now) with more expansive turns. Maybe then I won't have to listen to the growl of the exhaust. Then again, I can turn up the radio and go deaf.
The bends aren't causing the noise- the muffler might very well be, though. Having the exhaust terminate under the vehicle can cause a resonance or drone as well.

As to pipe bends, I saw a formula that says one 90 degree bend is equal to about 35 diameters of straight pipe, or one 90 degree bend in a 2.5" pipe equals about 8' of straight pipe. You have two of these but it's still not a deal killer unless the exhaust pipe diameter isn't sufficient. I'd want at the very least a 2.5" diameter exhaust system, 3" would be better but harder to package.

Link to formula- http://www.google.com/url?sa=t&rct=...Mzs1dIoLA&sig2=7znVcZslYzbktUh1-pGdzA&cad=rja. How this formula relates to things like Rayleigh flow I don't know- the main thing to take away from it all is that in a general sense, larger is better than smaller- be it bend radii, pipe diameter or flow in CFM (which can also allow more noise).
 

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The larger diameter pipe is what one muffler shop told me so I have to believe that is it. Thanks
What- that the larger pipe diameter is causing the excess noise? How big IS the exhaust pipe?

Where does the exhaust system end- under the vehicle? With or w/o a turn down? Or does it exit beyond the bodywork, or past the rear axle?

Lastly- what make and type muffler along w/the size?
 

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I was told by a muffler shop that if they have to use more than 270 degrees in bends for an exhaust they go one size larger. So if the engine required 2", then they would up it to 2.25 after 270 degrees.
You never mentioned what size exhaust your truck has, but if it's going into a single I'd go at least 2.5" and make the two pimaries 2.25 each. I don't think this will stop any vibration, and iff you don't want the "growl" then you need to go with a good free flowing, but quiet muffler and full tailpipe.
 
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