Power gains without cracking open the engine

Discussion in 'The BS Topic' started by COPO, Jan 24, 2021.

  1. gramps

    gramps Veteran Member

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    It’s mainly about the combination, and I agree going for that teenciest .25 of a hp is usually a waste and hurts the driveability.
    But it doesn’t hurt to try sometimes. While I had the last motor I built on the dyno 350 tbi engine, with a comp roller cam, EQ iron heads with vortec style chambers and a tbi intake pattern. We were running the stock gm tbi intake manifold, tbi unit I modified and the stock ecm. We were pretty happy with the way it ran, but I had this “stupid” tornado or some such name tbi spacer that I had acquired on a junk engine somewhere along the way. So for grins we slipped it under the tbi and made one more pull. I’ll be damned if it didn’t pick up another 8hp and like 10ft-lbs across the entire rpm range. It put that tbi motor across the 300hp mark - not bad eh!
     
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  2. G72Zed

    G72Zed Veteran Member

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    x2^^ 100% agree on this. I've gone up in 50cfm increments and things got better, the larger venturi helps slow things down to make the turns.

    Edelbrock had a "correction" factor based on CI/rpm/VE and intake style to set carb CFM from single to dual plane.
     
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  3. G72Zed

    G72Zed Veteran Member

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    Cool story, and that's what so fun about dyno testing, the sh!#t you can try out and what you can throw at it just to see what sticks....it's amazing what you learn, be it a +/- result, and in the EMC world, every point counts.
     
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  4. gramps

    gramps Veteran Member

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    Even the dyno guy was having fun. At one point we are making some adjustments and he says to me “be real interesting to see what it would do with a good intake and a 4bbl”
    Had we had more time I sure would have! But was trying to get that truck done for my father in law before he passed.
     
  5. Rosster

    Rosster Veteran Member Gold Member

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    Pocket protectors are common to see in the machinist trade. Mostly because you typically carry a quality 6” scale and a small mirror. When you lean over without a pocket protector, you scale always falls out- sometimes into stuff you really don’t want to reach in to retrieve. A quality starrett 6” scale was $15 back when I was in the trade in the 80s so you don’t want to lose one . Every single person in our machine shop wore one. Normally a pocket scribe, and a pen and pencil too. Now you know....
     
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  6. G72Zed

    G72Zed Veteran Member

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    Yep, some crazy stuff some days, just depends on the build. I have made some custom wooden "turtles" and spacers to try out. Wooden dowels and even Hockey sticks shoved in the bottom of the intakes all cut up, funny how some stuff works out.

    Ya don't know until your try.

    Intake turtle.jpg pic 2 (2).jpg
     
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  7. djorgensen3

    djorgensen3 Veteran Member

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    Did the turtles work at all?
     
  8. 73 Z

    73 Z Veteran Member Gold Member

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    Just add NOS if budget permits
     
  9. G72Zed

    G72Zed Veteran Member

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    Yep, as planned. It worked better in the mid range, but took a bit from the bottom and top, so the averages came out the same, just depends where you want the power to be.

    Dyno only shows so much, 3-500 rpm in a static state. will be testing this year again in car. Also need to make more spacers, sold all of them.
     
  10. 1980RS

    1980RS Veteran Member

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    Nice work, best place is to test them at the track not the dyno. My buddy said the 2" 4 hole tapered spacer would not help my car much last year, the car ran a tenth and half quicker on the BBC. Never got to try it out on the Vortec 406, but I will this year, he he.
     

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