BBC Build

Discussion in 'Engine Topic' started by Strange81Z, Apr 7, 2021.

  1. 1980RS

    1980RS Veteran Member

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    That's an old Super Stock trick for days gone by. I will tell you this, at a swap meet way back in the late '80's a swapper had a set of GM sq. port heads with about a 1/2" of epoxy on the port floor going to the sort turn and I asked what that was all about. He told me we ran them in our S/S class and knocked off the index by 1.4 sec. lower, I asked if they tore them down for that, his reply was "no we just left that day and made everyone wonder what we had done". I should have bought those heads from him, but $2800 for set of GM heads was a little steep back then. Over this winter I am going to make an attempt at making a raised runner peanut port head out of a junk oval port I have laying around, just want to see what it does on the bench.
     
  2. carhead22000

    carhead22000 oldblue

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    interesting let us know i have a set licking around...nobody and i mean nobody uses them around here.i had a set on my first 454.had a machinist do the work to them.car ran hard for me for being a young pup. thats the 13.3 engine i ran...went on its face at 5500.rpm..but man it was fun!!!!
     
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  3. Pentupfury

    Pentupfury New Member

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  4. Pentupfury

    Pentupfury New Member

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  5. 1980RS

    1980RS Veteran Member

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    Think about that for a second, why the engine fell on it's face at 5500 rpm. Was it the heads or something else? my 360 casting will go 6500 with ease but it's not the heads that make them do that rpm.
     
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  6. Greg Mc

    Greg Mc Veteran Member

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    The HotRod article is interesting.....yes the peanut port heads are below the others but I don't think they get destroyed like many would suggest. A lot of people feel the heads are garbage but I think they perform pretty well according to the comparison and the results that guys like 1980RS have with them. Now if you want to turn your BB 6500 they are not the head for you but they have very good TQ and HP numbers, those #s just happen at a lower rpm, which I don't think is a bad thing if you are looking for a good street/strip engine with some good longevity. I put mine together with a target max rpm of about 5500 and can't wait to get it finished up and see how it does. I also wonder what the TQ/HP numbers would be if they had started the pulls at 2200 rpm instead of 3200. Use the PP heads with a tight converter and they should get a heavy car moving nicely.
     
  7. carhead22000

    carhead22000 oldblue

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    if i,m not mistaken a 268 comp cam was the choice. 6500 is too high for my liking.yes it was a very mild 454.but it all worked great together.
     
  8. G72Zed

    G72Zed Veteran Member

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    Interesting article. Many ways to look at it. Leaving the PP GM head out, The Brodix head made the least TQ & HP per available CFM at the cams max lift, but made the most TQ and HP (tied with TFS) overall.

    By chance, although is had CNC chambers @ 110cc, the bigger thing that stands out to me is the Brodix head had the worst Ex to Int flow % ratio at 64.4% (.300-.550) and with a stock exhaust port location to boot. It had the best intake CFM @ .550 lift, and the smallest CC runner at 270cc.

    Key things I have learned, when comparing heads, I like to know were are the runner CC's coming from. You can't develop an exhaust port on a flow bench, some of the best heads have the worst exhaust port % ratios.

    Some heads on "the bench" are "CFM advertising queens" and there fast and sounds awful !!! Slow them down, and they make more power.
     
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  9. G72Zed

    G72Zed Veteran Member

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    I have 2 sets of my own SBC heads on the bench, the aluminum ones (Canfeild) are oval ports filled with Manley A/B and the Iron Sportsman II's are filled with J/B. I love that stuff....LOL
     
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  10. 1980RS

    1980RS Veteran Member

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    Let me see here, you filled the port floors and some in the bowl area.
     

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