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About yoloSun

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  • Cars
    1979 L20B Pickup
  • Interests
    VAGINA, cars.
  1. yoloSun

    cannon manifold 821

    Well I had a rough idle, and the carb wasn't responding to the air/fuel mixture screw being turned all the way out. I was tuning for pinging and top end power at the time of distributor adjustments - On a slightly inclined highway my speed was dropping to 60 Km, more gas did nothing but make a bogging sound. As for the rpm issue, I was asking a genuine question, what rpm is your engine at in fourth, above, say 80 Km, 40 MPH? This is the only 4-speed I've owned, so I am unsure. Just feels like the revs are too high without a 5th gear.
  2. yoloSun

    cannon manifold 821

    Well, my tach has been saying 4000-5500 above 80Km, or as you yanks say - 40 Miles per hour. I think I may be having some clutch slippage from a slave cylinder malfunction turning it into a hydraulic press and keeping the fork pressed in slightly, or maybe it was the vacuum leak. Take a look at my other post, theres pictures of my intake manifold with the EGR removed. Or do 4-speeds just take a shit ton of revs to go fast?
  3. yoloSun

    cannon manifold 821

    Heres an excerpt from this website :https://www.chevellestuff.net/tech/articles/vacuum/port_or_manifold.htm This was written by a former GM Engineer. "Now, to the widely-misunderstood manifold-vs.-ported vacuum aberration. After 30-40 years of controlling vacuum advance with full manifold vacuum, along came emissions requirements, years before catalytic converter technology had been developed, and all manner of crude band-aid systems were developed to try and reduce hydrocarbons and oxides of nitrogen in the exhaust stream. One of these band-aids was "ported spark", which moved the vacuum pickup orifice in the carburetor venturi from below the throttle plate (where it was exposed to full manifold vacuum at idle) to above the throttle plate, where it saw no manifold vacuum at all at idle. This meant the vacuum advance was inoperative at idle (retarding spark timing from its optimum value), and these applications also had VERY low initial static timing (usually 4 degrees or less, and some actually were set at 2 degrees AFTER TDC). This was done in order to increase exhaust gas temperature (due to "lighting the fire late") to improve the effectiveness of the "afterburning" of hydrocarbons by the air injected into the exhaust manifolds by the A.I.R. system; as a result, these engines ran like crap, and an enormous amount of wasted heat energy was transferred through the exhaust port walls into the coolant, causing them to run hot at idle - cylinder pressure fell off, engine temperatures went up, combustion efficiency went down the drain, and fuel economy went down with it. If you look at the centrifugal advance calibrations for these "ported spark, late-timed" engines, you'll see that instead of having 20 degrees of advance, they had up to 34 degrees of advance in the distributor, in order to get back to the 34-36 degrees "total timing" at high rpm wide-open throttle to get some of the performance back. The vacuum advance still worked at steady-state highway cruise (lean mixture = low emissions), but it was inoperative at idle, which caused all manner of problems - "ported vacuum" was strictly an early, pre-converter crude emissions strategy, and nothing more."
  4. yoloSun

    What was this?

    Those holes are going directly into the intake - soooo... the exhaust gasses are indeed entering the intake system. I think its part of the EGR system. If you look at the first picture, you can see all the way through the plenum to where it connects to the intake valves. I believe I read that the 78-79 l20b was the only intake that didn't use the exhaust to heat the intake; this intake has a coolent line for that purpose...I think. I don't think that was carbon...two inches of carbon...thats crazy. Ill check again. I'll post what was connected to it tomorrow so you guys can see.
  5. yoloSun

    What was this?

    Looks like two holes burned through a material that I'm going to guess was a filter. Was this causing a vacuum leak?
  6. yoloSun

    cannon manifold 821

    Yeah I'd like to do a single dcoe, with a lynx manifold. I will retroactively wait for good deals, maybe I'll get lucky. But does the lynx come with the coolent plumbing I wonder? I have the w58 head btw. '79 l20b.
  7. yoloSun

    cannon manifold 821

    Thanks guys, tried to check the timing before putting a fresh gaskets, but I couldn't see too well in the day time. Putting studs in sounds like a good plan to me, I'll have to look up the thread size.
  8. yoloSun

    cannon manifold 821

    Thanks guys I'll check with Pierce; the firing order thing makes sense, definitely something to consider. As for complaints, I don't know what they would be - though I read here that the single side draft carb is the most fun pennywise. I am in the process of changing the manifold gasket, previously the engine would not idle and bucked on excelleration, there was an air leak; I went over everything, got frustrated, took the carb on and off probably 15 times, torched a 12 mm wrench and made it custom for the carb bolts. Then I took the smog equipment off. Still to no avail, and that's when I noticed the EGR valve. Cupped it with my hands and the engine settled down, so I blocked it off, tuned the idle vacuum to 22-23 hg, where previous it was...maybe 15 hg. Advanced the timing because I was hearing pre detination, and changed the distributor vacuum advance from the carb to the manifold. The engine ran great, no more bucking or idle issues, excelleration was good, no pinging. Now it's talking to me again, idles a little rough. Tachometer jittering, idle mixture screw all the way out does not kill the engine, but Turning it in does kill it. I noticed the manifold is missing a bottom bolt, radiator side. So now I'm trying to get the bottom left manifold bolt off without a 12mm shallow swival socket. Fuuuuck. Also it looks like the intake has a coolent line going to it? Wondering what the procedure for that is.
  9. That makes sense, I'll check the pedal Freeplay, thanks alot dude.
  10. As far as I know the truck is stock, I had never heard of release collar lengths until just now, so thanks for the free education. I also googled 'release collar lengths' and learned about cervical collars. As It turns out you really don't need a longer rod, just a better cervical collar length. To clarify though, the rod went out and stayed out, kept the fork pushed all the way, and never came back until, the bleeder screw was turned to release pressure from gas or fluid. Perhaps a little of that is happening here?
  11. I had to bleed my slave cylinder, it's rod was pushed all the way out.
  12. yoloSun

    cannon manifold 821

    Hey guys, does a "cannon manifold 821" fit an L20B head? Scoured the net but came up empty.
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