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Thread: is redusing my 3 inch exhaust to a 2.25 tip bad?

  1. #1

    is redusing my 3 inch exhaust to a 2.25 tip bad?

    I am in the process of doing my custom 3" side exit...the tips i am using are the stock Z28 tips, rectangular style. They measure only a 2.25 ID inlet, but the outlet is 2.25x8, and i you have never seen one off the car check out the link to the picture below so you know what i am talking about...

    http://cgi.ebay.com/ebaymotors/93-97...ayphotohosting

    What i am wondering is if it will "restrict" and of my exhaust flow if i use a couple reducers to go from my 3 inch piping to the 2.25 on the tip? I wont go directly from 3-2.25, it will prolly be 3-2.75, then 2.75-2.5, and 2.5-2.25, so its a little smoother of a transition. I know the less restiction the better, but since its only going to be 2.25" piping for about 4 inches, then expand out to a 2.25x8.

    I also can cut the tip in half (seperate the top and bottom, like 2 pieces of bread from a sandwich, lol) and weld it up to the 3" pipe for the inlet with something filling the gap, but keep the stock size on the outlet side.

    If you have no idea what i mean let me know, i will try to explain it better, and get pics.

    Kris

  2. #2
    turbo addict Turbo Mopar Contributor Dave's Avatar
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    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    It's a bottleneck. Simple as that. I'd say screw the tips, go for performance. Sure your exhaust will flow like a mofo through the 3" of it, but now you're making it smaller? It will stack it up and basically make your 3" as useful as a 2.5".

  3. #3

    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    i talked to my buddy who welds for me tonite...he was saying i should splice the inlet side and widen it up to fit good onto the 3" pipe, then the rest of that tip is pretty wide still, so it shouldnt cause any restriction, what do you guys think of that?

  4. #4

    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    oh ya, i want to have a tip. I want the exhaust to be steathly looking and almost 'hidden', but still cool when you notice it after its pointed out. I dont wanna cut it before the side of the car and i dont want it to be seen by any law enforcment(its illegal to have side exit on a pass. car in CT)

  5. #5
    Hybrid booster
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    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    Yeah I agree major restriction doing it the way you first described. But like your buddy said it might be easy to work around. Ditch the idea of reducing it all the way down to 2.25" and see if you can cut off the inlet and have the 3" pipe welded straight onto the tip. If the diameter is too much maybe you could go into a oval 3" first and then into it.
    1991 Chrysler Lebaron GTC convertible - a568 - 15psi FWD Stage 3, FMIC, TII Garrett turbo, two of the big ones

  6. #6
    boostaholic
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    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    open the inlet of the tip up and weld it to the 3 inch it will work much beter than reducing it down to 2.25

  7. #7
    Hybrid booster
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    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    Yeah it'd be pretty easy to just oval the end of the 3inch pipe to have it fit deeper onto the Z28 tip, then just hack off the part of the z28 tip that goes to far into the 3inch oval'd pipe

  8. #8
    turbo addict Turbo Mopar Contributor
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    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    or run twin tips. That would work fine.

  9. #9
    Admin- "Alexandria" Ken... Comes W/4 Car Garage Turbo Mopar Staff GLHSKEN's Avatar
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    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    By tyhe time it reached the tips, The exhaust would have cooled considerable. (more dense). Could it hurt, yes. But it will not be severe...
    Ken Adler....
    Cars, A few (9)

  10. #10

    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    yea, the oval shape was brought up when a couple of us were sitting around my house last night checking it out. I thought about hammering and putting it in the vice lightly to get it to a good oval, then cutting the tip like you guys also said.

    i will try that, and if it doesnt work i have another one to experiment with, and i can always buy the 2 off ebay in the link in my first post, lol.

    thanks for everyones opinion, and i think on mondya i am going to be welding some stuff up, i'll be sure to take pics

  11. #11

    Re: is redusing my 3 inch exhaust to a 2.25 tip bad?

    well i went out after posting earlier adn hammered a 3" pipe to a oval/rectangleish pipe. I matched it up with the tip and cut off about 4 inchs from the inlet side of the tip. Tack welded it, then hammered the parts still a little round to be flat with the tip and welded it up. looks great and i am so happy with it, and i let my sister take my camera to spain for the next 2 weeks so i cant get a pic yet! I will get on ASAP. It basically goes from a 3" round to a 4x2.25, and is a REALLY smooth transiton. Shouldnt cause any restriction.

    thanks again guys, i'll get a pic up soon

    Kris

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