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By HoLun - 11 Years Ago
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Well I was fed up with the lack of tunability of the carter, and infinite leaks of the holley and bought the summit carb. its basically an autolite 4100/holley 4010 with replaceable accelerator pump nozzle, idle feed restrictor, adjustable vacuum secondary, uses holley parts for jets, pump cam, pump, powervalve etc.
i was going to fudge with the mint 4100 that i have, ie drilling for IFR, but with a good 4100 goes for as much if not more then the summit carb, theres no point.
and i was able to make the engine run super smooth. very responsive and crisp throttle response, anymore i need to go fuel injection.
so the engine is basically stock with +.030 bore, 1.54rockers C0AE head opened up to 1.72 exhaust valves, and with this clay smith cam - intake open 28 close 64 exhaust open 64 close28 duration 224 ; lift .446
wont idle under 1000 rpm with 4 hole spacer, but low rpm response is almost perfect, idles with about 12in vacuum.
heres some pic.
20131116_153213
20131116_153225
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By Y block Billy - 11 Years Ago
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Mummert has used them with good success and I put one on a 56 F100 I worked on for a guy and I am impressed with that carb. I could hold at any rpm and it was just crisp, never skipped or stumbled anywhere along the rpm range.
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By Lord Gaga - 11 Years Ago
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I think your manifold vacuum should be more than 12 in with that mild cam. Have you checked for vacuum leaks?
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By HoLun - 11 Years Ago
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I checked all the vacuum connection points, but i have not actually checked where the manifold connects to the heads, I'll do that later.
it was idling at 800rpm with 20in HG but the valve lash was at double the spec of the cam card, I adjusted to .018 as indicated on the card and the vacuum dropped to 12, but it pulls really good after 2500rpm.
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By PF Arcand - 11 Years Ago
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I'm with LG, there's something out of wack there. Were the rockers really noisy at the original setting?. Seems weird that apparently setting the clearances correctly, according to the card, dropped the vacuum that much & messed up the idle
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By The Horvaths - 11 Years Ago
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Was the cam degree checked when the engine was built? I would double check timing and advance curve too, perhaps the damper ring slipped.
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By GREENBIRD56 - 11 Years Ago
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Holun - Will she behave if you block the PCV?
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By The Horvaths - 11 Years Ago
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Holun - Will she behave if you block the PCV?
That is a very good question.
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