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SHE LIVES !!!!!!!! and crappy hesitation.....
https://www.slantsix.org/forum/viewtopic.php?t=40977
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Author:  wjajr [ Tue Jul 13, 2010 4:52 pm ]
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Vacuum leak?

Author:  Volare4life [ Tue Jul 13, 2010 5:35 pm ]
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not that i can tell, i wonder if i drill holes in the throttle blades kinda like an air bypass if that would work....... but if it doesn't then i am out 4 throttle blades.......

ok question, will a stock holley 390cfm need to be detuned to run on stock slant, with just an intake (for now at least) ??


-Mike

Author:  wjajr [ Wed Jul 14, 2010 5:36 am ]
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Mike,

Don’t drill anything. Drilling is for when there is a real aggressive cam with a lot of over lap, the engine has low or a poor vacuum signal at idle, and has to be done incrementally starting small and working up in drill size.

The 390 will work, but because your engine is stock, and can’t pump much air, the engine won’t be able to take advantage of the secondary circuit. It will be wasting your money both in hardware & non performance.

Think of this example:
Let’s say you like beer, you can drink a lot of the stuff for hours on end non stop. You’re an efficient beer digesting pump. Beer in = beer out, no spilling, no gagging just a well oiled machine hoisting away…

One hot day you decide that by cutting the top off of a can of beer you will be able to get more of the golden nectar down your gullet, thus consuming more beer at a faster rate, than using the manufacturer’s factory opening; a promising hypothesis indeed.

After experimenting for a few 16 ouncer’s & than over to 12 ounce beers, you find that: one you can empty a beer faster; two the beer goes down at the same rate as always; three there was a lot of coughing & sputtering & wasted beer while downing those beers.

A bigger funnel won’t help, neither will Budweiser engineering.

You have to match the size of the carburetor to the displacement & build of an engine. This is nothing more than a mathematical manipulation. Here, play with this sizing tool developed by Holley.

By the way I had to drill my 390 due to an aggressive cam. Those holes can be easily soldered up, resized, and soldered up again. It is a PIA using trial & error hole sizing, mounting and un-mounting the carburetor each time a new size hole is drilled, and than jump in for a test drive.

Oh, one only drills the primary throttle plates...

Author:  Aggressive Ted [ Wed Jul 14, 2010 11:00 am ]
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Vacuum leak....

What does your vacuum gauge read?

Author:  Volare4life [ Thu Jul 15, 2010 7:00 pm ]
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don't have a vaccuum guage, i put the stock 2bbl back on and she just cranks and cranks, I am thinking timing, that and i have my wooden spacer between the cliffy manifold and carb, maybe its not seated, when i got the manifold i didn't get the carb adapter just the manifold. I would love to get my other cam in 280/270 oregon regrind in but i still need cam bearings,

doing the nasty deed tomorrorw, but more than likely tonight into tomorrow, pull valve cover, pull all the plugs and wires and dizzy cap, find #1TDC and when the intake valve is its most open, set the dizzy to the number one spot and crank and hope she fires

-Mike

Author:  hellion_locdogg [ Thu Jul 15, 2010 7:23 pm ]
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"pull valve cover, pull all the plugs and wires and dizzy cap, find #1TDC and when the intake valve is its most open, set the dizzy to the number one spot "

There are much easier ways to do this.

,Cliff

Author:  ceej [ Thu Jul 15, 2010 8:38 pm ]
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Quote:
find #1TDC and when the intake valve is its most open, set the dizzy to the number one spot and crank and hope she fires
:shock:


Nnnnnoooooooooo! keep a fire extinguisher handy if your going to do that.

When on base circle for #1, both valves closed, TDC, that's the spot. Fire cylinder 1 just a tad before that. Five to ten degrees will do you.

CJ

Author:  Volare4life [ Thu Jul 15, 2010 9:17 pm ]
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cliff please explain,

ceej you got me confused brother,

this whole things cunfusing the sh!t outta me,

-Mike

Author:  hellion_locdogg [ Thu Jul 15, 2010 9:46 pm ]
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This is how I do it:

take out #1 plug
roll motor over till #1 is up, use a thin dowel or coat hanger as indicator
note- #1 & #6 travel together
If your timing marks are lined up on crank its #1 tdc if not you're on #6, keep rolling
rearange plug wires so #1 is on cap where rotor points

No need to pull valve cover. I've been told this does not work, but #1 & #6 do NOT fire at the same time. I've never been 180 out. This worked for me even when I had no pointer for timing marks.

,Cliff

Author:  wjajr [ Fri Jul 16, 2010 6:01 am ]
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hellion_locdogg:

[quote]"pull valve cover, pull all the plugs and wires and dizzy cap, find #1TDC and when the intake valve is its most open, set the dizzy to the number one spot "][/quote]

[quote]cliff please explain,

ceej you got me confused brother,

this whole things cunfusing the sh!t outta me,

-Mike[/quote]


Mike,
Perhaps there is a bit of confusion here as to just what is happening in your engine when trying to set its static timing on a four cycle engine. In other words, adjusting the distributor, to fire-off #1 cylinder at the correct time, during the Otto cycle. Otto was the guy to first build a 4 cycle engine in the late 1800’s.

I have found an animated [url=http://www.howstuffworks.com/engine1.htm] 4 cycle engine[/url] running through its four cycles.

Here is what you have to do to time a slant:

A, Move #1 piston (closest to fan) to “Top Dead Centerâ€￾ (all the way to the top of the bore so it neither going up or down) between #2 “Compressionâ€￾ phase in the cartoon, and #3 Combustion phase. (pay close attention to the animated valve's positions) The timing mark on the crank shaft pulley should be at TDC mark aligned with the timing tab.

B, Set your distributor rotor button, by loosening the bolt holding the distributor to the block, just enough to turn distributor by hand, & turn it to point to where #1cylinder’s plug wire would be if the distributor cap were mounted in place. This would be in the direction of five o’clock.

You have now set the timing to Zero degrees TDC.

The engine should start right up, may run a little slow or lumpy, at which point you will need to reach down and slowly rotate the distributor a little bit until the engine runs a bit better.

Now check your timing mark with a timing light to see if it is where it should be, and adjust as needed.

Author:  Volare4life [ Sat Jul 17, 2010 12:34 pm ]
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real quick should the fuel pump pulse ?? i mean you can see and feel the rubber line pulsing with each pump ??

Author:  wjajr [ Sat Jul 17, 2010 12:57 pm ]
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I would say no to the pulsating fuel line. Pick up a new length and install it as soon as you can before the old one splits and antagonizes the fire gods…

Look at the fuel line mod at the top of this "engine" page.

How did you make out with timing the engine?

Author:  Volare4life [ Sat Jul 17, 2010 4:40 pm ]
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its brand new rubber line, i may swap the pump with the one that was on the motor, dunno why its pusling..... not sure about the timing batt was dead and is on the charger now. I also pulled the old dizzy and put in my new reman unit, hand cranked the motor over brought #1 piston up to TDC and checked the balancer, the mark on the crank pulley was at 0 on the timing tab i also changed the dizzy hold down to the one off the '79 which allows an amazing amount of adjustment, so we will see,


-Mike

Author:  ceej [ Sat Jul 17, 2010 5:57 pm ]
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OK, I just re-read your first post. Please take a picture of the top of the carburetor for me. I want to see the top of this Edelbrock with the air cleaner off. I suspect something.... :shock:

CJ

Edit: What this is about. Make sure the secondary air valve is in the carburetor. There are two sets of butterflies in the secondary circuit. One is mechanical, in the throttle plate, the other set have weights on the outside of the secondary bores, and those butterflies are opened by air demand. If the second set of butterfies isn't there, your going to experience exactly what you described.

Author:  Volare4life [ Sat Jul 17, 2010 8:02 pm ]
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hoy sh!t yea when i got the carb from the guy he had taken the balancer weights out but i got them and can install them not hard at all, but just a quick update,

I removed the wood spacer it was badly cracked, put the carter 2bbl on with a carb adapter obviously.

lined up the balancer with #1 piston TDC according to the timing mark on the tab and balancer, tried cranking it over.....nothing flipped the wires 180......nothing i think it might be an internal timing issue but alas i will do like i did before and put the wires back to where they were and move them one spot over crank repeat till she starts,

pics to follow, dinner now

-Mike

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