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Hot Rods Exhaust pipe--different lengths?

Discussion in 'The Hokey Ass Message Board' started by lonejacklarry, Sep 8, 2020.

  1. lonejacklarry
    Joined: Sep 11, 2013
    Posts: 1,498

    lonejacklarry
    ALLIANCE MEMBER

    I am building a '54 Dodge 1/2 ton pickup with an almost stock 230 c.i. inline 6 engine. I have a split manifold set up to the 120 hp 6 and, therefore I need two exhaust pipes.

    The problem: The easy way would be to run the two pipes all the way back (with a crossover) and have them exit together on the right rear. This look mimics the European model for exhaust and I do not like that look.

    I realize there is a great amount of science and expertise that goes into a really good exhaust system. My situation is a small displacement inline 6 that is not going to generate massive horsepower to begin with. If one were to have one of the pipes crossover (somehow) and one come out the left rear and the other come out the right rear would it greatly alter the performance or sound? On the surface it would entail having one pipe considerable longer than the other but would it matter with my low HP setup?
     
  2. Just run a crossover under the motor; like was done on most V-8 cars with single exhaust. Don't think the length is something you really need to worry about.
     
    dirty old man likes this.
  3. In your case, the "dual tips" are mostly for cosmetic reasons, so don't over-think it. Just position the tips the way that pleases you the best. There is little to no sound or power concerns to worry about.

    Here's the "European exhaust" that was on my truck when I bought it. LOL :p
    panel-truck-15 (2).jpg
     
    Last edited: Sep 8, 2020
  4. Beanscoot
    Joined: May 14, 2008
    Posts: 3,075

    Beanscoot
    Member

    I doubt the different lengths would cause any issues. I'm thinking of Ford small blocks which typically had fairly swoopy free flowing manifolds on the right side, and straight logs on the left.
    Those must have flowed quite a bit differently.
     

  5. BamaMav
    Joined: Jun 19, 2011
    Posts: 6,737

    BamaMav
    Member
    from Berry, AL

    Can you come back with the two pipes to the center of the bumper, like a late model Corvette? It wouldn’t have that one sided Euro look as bad....
     
  6. yellow dog
    Joined: Oct 15, 2011
    Posts: 512

    yellow dog
    Member
    from san diego

    jnaki likes this.
  7. fastcar1953
    Joined: Oct 23, 2009
    Posts: 3,602

    fastcar1953
    Member

    I doubt the lengths will matter. This one's kid approved.
     
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  8. It doesn't matter. Power boost obtained in headers occurs in a) individual pipes for each cylinder, and b) within a length shorter than 3'. It is based on the speed of sound in hot gasses (about 1100ft/sec). From there to the end of the system, goal is to minimize pressure losses with large enough tubing diameter.
     
    dirty old man likes this.
  9. rusty rocket
    Joined: Oct 30, 2011
    Posts: 5,068

    rusty rocket
    Member

    Just run one big one like I did. Hahaha! 15B6ADA3-5F87-42F2-B39B-760221B5AB52.jpeg
     
    i.rant and willys36 like this.
  10. As said it will make zero difference. The exhaust in my Fargo crosses over at the front, runs down the right side then back to the left side to exit


    Sent from my iPhone using H.A.M.B.
     
  11. fordor41
    Joined: Jul 2, 2008
    Posts: 1,017

    fordor41
    Member

    '65 ford wagons with v-8 had P.S. exhaust exit on drivers side and visa-versa. they crossed behind the rear end
     
  12. jimmy six
    Joined: Mar 21, 2006
    Posts: 14,885

    jimmy six
    ALLIANCE MEMBER

    Why not do this. Nobody says you need to see them. 2542239F-3A29-426C-80E8-5D1FBC6291E7.jpeg
     
    tomkelly88 likes this.
  13. Mr48chev
    Joined: Dec 28, 2007
    Posts: 33,931

    Mr48chev
    ALLIANCE MEMBER

    Not worth getting you undies in a wad over for sure. Power sure isn't an issue and as others said, run the pipes out the way you personally want them to and leave it at that. I'm not a fan of any pipes dumping under the rig though I want the exhaust out from under the whole rig.
     
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  14. 41rodderz
    Joined: Sep 27, 2010
    Posts: 6,541

    41rodderz
    Member
    from Oregon

    I agree with Mr48chev. I use to not mind dumps but I prefer not the one smelling exhaust anymore.
     
  15. Fortunateson
    Joined: Apr 30, 2012
    Posts: 5,352

    Fortunateson
    Member

    Olden days exhaust had an door that I found pleasing in small does of course. Today's exhaust don't smell as pleasant which I believe is due to oxygenated fuel.
     
  16. 54vicky
    Joined: Dec 13, 2011
    Posts: 1,599

    54vicky
    Member

    I doubt you need a balance tube no matter what you decide.they were designed to keep the exhaust pulses drawing the exhaust out to aid in flow.more technical but you get the idea
     
  17. The vast majority of the cars being built today have unequal length exhaust pipes. People like to think that exhaust systems are designed to boost performance, but for virtually all "daily driver" vehicles, the exhaust is designed to fit under the car. If that means putting a flat here or there, they do it. If that means running the left side two feet further than the right, that's what they do. Ford builds over 700,000 F150s every year, each one of them (other than Raptor maybe) has a longer exhaust routing for the left side than the right.

    A lot more work goes into how it sounds than getting the most power out of the system. Back when I used to do exhaust development the priorites were emissions followed by sound. Power? You got what you got. (With the exception of a performance vehicle or something like the flagship pickup truck powertrain) EDIT: All of which assumes it fits under the car and meets the clearance requirements. If that means oval pipes and or dents and or flat sections then that's what happens.

    I don't think lengths after the crossover will effect anything but the sound...
     
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  18. lonejacklarry
    Joined: Sep 11, 2013
    Posts: 1,498

    lonejacklarry
    ALLIANCE MEMBER

    Ok, thanks to all. I think I will have one a couple feet longer than the other and it will work (and look) fine. I'm going to try to get the crossover under the bed instead of under the cab--maybe a little cooler in the cab.

    Thanks, again!
     
  19. jnaki
    Joined: Jan 1, 2015
    Posts: 9,366

    jnaki

    Hello,

    The length of the exhaust pipe does little for performance. Unless they are equal length individual header pipes, the most stock exhaust set up is usually fine. The problem is if you cut the total length short for fancy outlets and exit routes, that causes noise problems possible fumes where you don’t want them.

    When we got our tubular Corvette mufflers on the 58 Impala, we knew we had to have our local muffler shop, re do the complete exhaust system. But, we had him take off the restrictive stock mufflers and install the straight through Corvette tube mufflers. Since the muffler man was going to finish the job at his leisure, we drove away with just the tube mufflers on and not other exhaust pipes running out of the rear of the sedan.

    As far as performance, at the drags, it sounded nice, passed inspection as a factory stock muffler (Chevrolet parts book) and the times were slightly better. But, others questioned the no rear exhaust stock exhaust pipes as most had on their cars. So, it was one time only in this set up at the drags. Even though we had mufflers, it sounded like uncorked open exhausts on our stock Impala.

    We later drove it to our Bixby Knolls cruising grounds, made the grand entrance and parked. Everyone wanted to know about the new “headers” on our Impala. Idling in the parking lot was very cool, but we all noticed the exhaust fumes just drifting up and into the seating areas. When we drove away, the fumes seemed to disappear, but the sound was outstanding. We were probably secretly inhaling noxious fumes and we did not know it.

    Jnaki

    Our next day job was to use a short tube with a chrome tip on it to route the exhaust out of the side before the rear wheel. The sound was a little different, but still loud. The fumes seemed to go away with the windows rolled up, but when they were down, it came back like gangbusters.

    One final try at the exhaust looking cool and in a different place was just behind the rear wheel. We thought that this place was fine as the spinning wheel would take the exhaust smoke and sent it out and around the back, so we could not smell the fumes. It worked a little better, looked cool, but was not the answer. By this time, our local welder at the muffler shop had finished the completed rear length exhaust system and installed it.

    Now, the first thing was the exhaust being quiet with the dual chrome tips facing the rear under the chrome bumper. The Impala just seemed to be happy with this set up. If we wanted to hear the loud exhaust, we still had the two down tube exhaust capped openings directly beneath the stock headers.


    The Impala was still fast, sounded very nice/fairly quiet and we all knew our clothes/brains were not being affected by the noxious fumes.
    upload_2020-9-20_3-59-56.png
     
    Last edited: Sep 20, 2020
    dirty old man likes this.
  20. ekimneirbo
    Joined: Apr 29, 2017
    Posts: 4,258

    ekimneirbo

    Unless you did an awful lot of snakeing the longer tube around many things so that it caused backpressure from all the turns, it really doesn't matter much what it does after its gone thru your mufflers. I always liked the looks of two round pipes sticking out the back......one on each side. Usually about 2 1/2" in diameter. I agree with you, that two on one side looks hokey.
     
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  21. Atwater Mike
    Joined: May 31, 2002
    Posts: 11,625

    Atwater Mike
    Member

    Conversely, I recall near the last days of Baylands strip (Fremont, CA) there were some serious racers with dual purpose cars, members of the 'INLINERS'...Yep, most had inline sixes, but there were a couple of straight-8 Buicks.
    At least 5 of the members' cars had two pipes out the back, on one side...Heralding the fact that they were indeed 'Inline Powered'.
    Naturally, I thought it was 'cool'. Two pipes on one side is a statement, therefore.
    Just another way to look at it.
    In 1955, Billy Souza cut the muffler out of his '41 Chevy, substituted a piece of exhaust tubing in there, 'Straight pipe'...He fastened a dummy tip to the other side, looked like 'duals'.
    Big thing then was to 'Rap out your pipes'! So, we ranted: "Billy! Rap out your PIPE!" :D
     
  22. ekimneirbo
    Joined: Apr 29, 2017
    Posts: 4,258

    ekimneirbo

    Yeah, but everybody knows how "flaky" California is. I'd just consider that as one more reason NOT to do it............




    Just kiddin:p
     

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