When does a 67 BB Intake begin to restrict?

Discussion in 'The Bench' started by johnriv67, Aug 25, 2019.

  1. johnriv67

    johnriv67 Well-Known Member

    Im planning for the future and I am wondering when the stock 67 intake begins to cost power. I’m likely making around 350-360 hp right now, when would it become a restriction of even a few horsepower over an Edelbrock Performer or B4B?
  2. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    When you port the heads to increase their air flow or use good aluminum heads and a cam that requires more air flow than the intake can flow. If you put a good vacuum gauge on the engine that you can monitor, run the car at WOT. If you see vacuum at WOT, there is a restriction somewhere. I believe the SP1 will flow more air than the cylinder head, think I read that somewhere. Yeah, TA's description,

    Last edited: Aug 25, 2019
  3. the Edelbrock intake does not flow any better than a stock intake. The only advantage is weight so the 67 intake will never be a restriction versus the Edelbrock.
  4. johnriv67

    johnriv67 Well-Known Member

    Ok that is good to know, since I am looking to buy a set of ported heads to install this winter.

    BQUICK Gold Level Contributor

    Any flow test to prove this? I seem to remember Greg Tomlinson posted flow numbers in an old GSxtra that showed better flow. Also being aluminum it is easier to port and equalize the runners. Many people back in the day bolted B4Bs on and then had no gain but with more air you need more fuel. Once jetted up (and stagger jetted) .15 ET reduction was realistic gain....
    Julian likes this.
  6. JW said there is no gain other than weight reduction more than once here on the Board. of course that's going to change if you port the Edelbrock intake but out of the box there is no performance improvement
  7. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Pretty sure I have posted these before, but here they are again,

    IntakeManifoldArt1.jpg IntakeManifoldArt2.jpg IntakeManifoldArt3.jpg IntakeManifoldArt4.jpg
    Julian, lemmy-67, kowalski and 3 others like this.

    BQUICK Gold Level Contributor

    Obviously from this data the B4B flows more air....
    Thanks Larry....I lent all my GSXTRAs to someone who never returned them.....
    I see the SP1 blew all others away as single quad...I wonder how the TA revised Wildcat would have fared under the same test?
    And what happened to Gregg Tomlinson???
  9. hugger

    hugger Well-Known Member

    Gregg passed away suddenly iirc
  10. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    I think it might depend on the rest of your combination and tuning.
    GranSportSedan likes this.
  11. GS Kubisch

    GS Kubisch THE "CUT-UP" BUICK

    Jason Line is doing pretty well with an iron intake...;)

    I had a very mild 430 that didn't pick up anything with and old B4B in place of the iron intake. This was track tested, no flow numbers or dyno testing. Car ran mid 12s at 3820lbs so probably very similar power to the OP.
  12. johnriv67

    johnriv67 Well-Known Member

    Revitalizing this thread, what amount of stagger jetting is correct for the B4B for it to perform best?
  13. Mule

    Mule Active Member

    John, I'm sure you got your answer by now, but stumbled across this while doing some digging:
    greatscat-Same except B4B had a longer runner to #1, so to compensate we'd run one jet size bigger on the primary driver side.
    BQUICK-Same here...had to stagger jet driver's side up to .003 more on B4B.....until I had it equalized by Tomlinson. Ran smoother as well....
    johnriv67 likes this.

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