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7.3 idi exhaust

Discussion in '6.9L IH & 7.3L IDI Diesels' started by Darrell Martin, Apr 16, 2021.

  1. Darrell Martin

    Darrell Martin Registered User

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    I read somewhere that you can delete all exhaust on these. ? They said to straight pipe it and it gives a really nice hum. Is this true? It's a 1990 Bus.
     
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  2. Farmer Rock

    Farmer Rock just a fella' without a 10mm socket

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    Deleting everything as far as just replacing the Y pipe and back with straight pipe. But if your exhaust is in good shape, you can just delete the muffler and replace it with a straight pipe. Straight pipes on these trucks sound like a big block gasser at high rpms. They sound really good and do have a throaty hum to them.


    Rock
     
  3. Greenie

    Greenie Registered User

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    A turbo charger will quiet the exhaust a lot but without a turbo the exhaust noise would be obnoxious. A friend had a 6.5 GMC with a glass pack (and turbo) that sounded great.
     
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  4. cozinsky

    cozinsky Full Access Member

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    Straight pipe would be pretty loud. Before I put a turbo on mine I had dual exhaust with glass packs. It sounded great until you got to around 2300 rpm, then it turned into an obnoxious cackle. I imagine with straight pipes it would be much worse.
     
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  5. franklin2

    franklin2 Full Access Member

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    N/A diesel without a muffler is a cop caller. Just like the diesels that blow all the black smoke. You see with the new diesels what blowing black smoke has led to.
     
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  6. Fredrickson

    Fredrickson Full Access Member

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    Sorry.. I was just having visions of your bus with big chrome dual stacks.. 'cool bus across the front. (and Elvis style sunglasses on the dash)
     
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  7. hacked89

    hacked89 Full Access Member

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    You can delete all the exhaust on anything with the right attitude.

    Mine was NA straight piped and sounded like a straight piped gasser so if you like that go for it.

    Sent from my SM-G955U using Tapatalk
     
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  8. IDIBRONCO

    IDIBRONCO IDIBRONCO

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    Do you like to ride a Harley with straight pipes? Do you ride it around constantly and take it on long trips? If so, then I guess you'd like your N/A IDI with straight pipes. Personally, I don't like either. Here's something else that I've noticed. When I first got my 1986 Bronco, it had a 302 with wore out glass packs on it. The exhaust ended right in front of the rear axle. It was pretty loud inside the Bronco. After I put the 6.9 in my Bronco, I took the exhaust that had been on there and put it on my Red Truck (81 F150). It doesn't sound nearly as loud on it. I think it has to do with the exhaust exiting underneath the cab of the bronco versus under the bed of the F150. I would think that since you have a bus, it would make the exhaust seem to be even louder that it would on a truck. I would say the same thing about a van.
     
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  9. Darrell Martin

    Darrell Martin Registered User

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    LOL
     
  10. Darrell Martin

    Darrell Martin Registered User

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    I actually do have my bike straight piped at the time. My baffles are removed temporarily, one tab broke and I haven't had it welded back yet. Your right it is kinda loud. I just read it somewhere that it sounded good and gave a few extra ponies.
     
  11. BrandonMag

    BrandonMag Dana 50 rebuilder Supporting Member

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    My '89 F-250 4×4 was turbo'd with a custom 2.5" to 4" to 5" exhaust that ended in front of the passenger rear tire with no muffler. If I put the go pedal down hard once it reached 2K RPM and above it was LOUD. But while driving around town and cruising at 60 on the freeway it sounded great: deep and throaty but not too loud and no drone.
     
  12. SuperDave

    SuperDave Full Access Member

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    My idi bronco is straight piped and is also obnoxiously loud inside, it's not bad at all under light acceleration and cruising but hard acceleration and under any load at all it is very loud. I was honestly planning to do a single in, dual out flowmaster with some old skool chrome megaphones exiting on either side of the receiver hitch. A lot of people like the way the straight pipe sounds though ,I have been complimented several times and even flagged down twice by people wanting to know what setup I have and both times they were absolutely flabbergasted that an idi with no turbo sounds like it does. I tell them it's the high compression which seems to go right over their heads.
     
  13. Darrell Martin

    Darrell Martin Registered User

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    Do you have a video that I can hear?
     
  14. Farmer Rock

    Farmer Rock just a fella' without a 10mm socket

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    there are lots of videos on youtube, just search 7.3 idi straight piped.




    Rock
     
  15. Clb

    Clb Another old truck Supporting Member

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    Fukkin noize makin junk
    Like the field worker across the street from me thinks daily.....Oh pardon my 6" straight piped 24v dodge junk as I rattle yer windows a hunnert yards away, on the limiter spring!
    Screw that.
    to bad diamond eye dropped the ball tho!


    Carry on
     
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