SHOULD I UPGRADE MY EXHAUST?

Discussion in 'High Performance Modifications' started by Z28-79, Jul 22, 2019.

  1. 1980RS

    1980RS Veteran Member

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    My lower compression BBC stuff is like that. I had one with 2" headers the car ran the best of 12.09, switched to 1 3/4" headers and the car ran 11.87 and I picked up 2 mph. It's all gotta work together. Just bought some merge collectors for my 2" Super Comps to bump up the tq. on those baby's.
     
  2. G72Zed

    G72Zed Veteran Member

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    Yep, same experience here.
    Please share what the merge collectors give you if it's a back to back test.

    I had good results with the ones I built, not as extensive as a Burns or anything, but an improvement, still use them.

    Used/tested the 4 into 2 into 1 from Flowmaster in the early 90's!!, holy crap, they did not like my setup lol!!

    Some work so well you need to re-tune and maybe re cam to take full advantage of them.
     
  3. 77 cruiser

    77 cruiser Veteran Member

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    I wish I would have done some back to back testing of headers. I built a set of 4-2-1 headers for the 421 I put in my Monte.
    I had it on an engine dyno but never tried any of the dyno headers he had.
    BTW the guy I had give me guidance for building the headers told me to stay with 2.5 inch all the way back, but I went with 3 inch.
     

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