timing issues
joe68
09-08-2012, 08:57 PM
ok i need some direction, i have a 350 .030 mild cam, pretty much stock not racial, i have gone thru the process of timing from TDC and i still get a pop out of carb when acer, fast. i have install new wires twice, cap and plugs just for good measure, now here are the issue: 1)the rotor does not quite point to number one plug? 2) I have move wires over both direction by one and and you guess it engine will not start unless timing is very advance? 3) when driveen down the road the car is fine unless i step into it, then it a very slow increase, not what i think think it shoud be or feel.4) i have roller rocker, and not a 100 percent that i have them adjusted just right, can this be causing two problem 1) one minute i have have vacum and the next day i do not 2) and i get a pop when steping into it. getting ready to buy a ford!!
Blue Bowtie
09-09-2012, 08:26 AM
With a stock distributor gear (13T), each tooth is about 27° of distributor rotation, so being one tooth off the design position would place the distributor that far off. It's mostly irrelevant if you're rotated the distributor to compensate. I'd be more concerned about valve timing.
joe68
09-09-2012, 10:35 AM
i am readjusting the valves again, but i have a question?
have anybody seen a dist. with a drive gear that was not just right?
maybe off a little with gears?
have anybody seen a dist. with a drive gear that was not just right?
maybe off a little with gears?
Blue Bowtie
09-09-2012, 10:31 PM
Even if the gear is machined or pinned in a position off the design or optimal position, it is mostly irrelevant. The distributor is timed by the shaft (no matter where it might be) from the points or HEI pickup coil to the rotor and cap. If the gear is "off" the position of the distributor may only be in a different position than pointing directly at the #1 hole, but as long as the rotor is aligned with the terminal for the #1 plug wire it doesn't matter.
One possibility is a problem within the distributor. If the centrifugal advance mechanism is sticking, slipped, or otherwise damaged, the position of the rotor in relation to the cap might be slightly off during firing. As RPM increases and advance increases, spark may try to fire to an adjacent terminal rather than the intended terminal (cross-firing).
One possibility is a problem within the distributor. If the centrifugal advance mechanism is sticking, slipped, or otherwise damaged, the position of the rotor in relation to the cap might be slightly off during firing. As RPM increases and advance increases, spark may try to fire to an adjacent terminal rather than the intended terminal (cross-firing).
joe68
09-13-2012, 07:43 AM
well redid valves and for the most part , they where right on,
but you where right , i have a vacum advance sticking, not sure why yet,
one times i have it and then it gone that when i would get a pop out of it,
looking into changeing dist.boy have they gotten expensive!
but you where right , i have a vacum advance sticking, not sure why yet,
one times i have it and then it gone that when i would get a pop out of it,
looking into changeing dist.boy have they gotten expensive!
mdcamaro
09-14-2012, 07:12 PM
Is this a stock dist? If so a vacuum advance is cheap also buy new hose. How are you setting the timing? Do you have a light where you can set the timing at 30 degrees? Did you put a vacuum gauge on the carb port and rev the engine? When timing the engine at idle does the mark jump around? (Timing Chain)
joe68
09-14-2012, 10:28 PM
well here is the update, started at the beginning and ,said it probably something stupid,
so i notice that the secondary where stuck and never opening, remove carb and found nothing hanging up, put back on and it hung up again, after back and forth notice that the choke was not letting the secondary open what so ever, re work choke and engine seems to breath better, can't road test till tomorrow, "hope for the best". i notice that i had more vacum on driver side carb port then passinger side after useing vacum guage to check, so i reverse vacum lines and it ran and sounded great, no pops! now is that a good thing to do?
i will test drive tomorrow with dist. vacum on passenger side, i also notice the gasket i had was four holes on a spread board manifold, so i change gaskets to a square hole and that also seem to help. my question is would a spacer help me create more vacum? the timing does not jump, brand new chain when engine was built, i have a standard timing light so no dial to advance, what i did was probably was not right , but i time it by sound and just gut feeling and that put the mark set at 18 with out vacum after i check with again with light, advance timimg is around 30 so i will test drive in the morning to wake up the neighbor hood!and give a report later
so i notice that the secondary where stuck and never opening, remove carb and found nothing hanging up, put back on and it hung up again, after back and forth notice that the choke was not letting the secondary open what so ever, re work choke and engine seems to breath better, can't road test till tomorrow, "hope for the best". i notice that i had more vacum on driver side carb port then passinger side after useing vacum guage to check, so i reverse vacum lines and it ran and sounded great, no pops! now is that a good thing to do?
i will test drive tomorrow with dist. vacum on passenger side, i also notice the gasket i had was four holes on a spread board manifold, so i change gaskets to a square hole and that also seem to help. my question is would a spacer help me create more vacum? the timing does not jump, brand new chain when engine was built, i have a standard timing light so no dial to advance, what i did was probably was not right , but i time it by sound and just gut feeling and that put the mark set at 18 with out vacum after i check with again with light, advance timimg is around 30 so i will test drive in the morning to wake up the neighbor hood!and give a report later
DeltaP
09-15-2012, 02:42 PM
You taking your vacuum source above the throttle plates or below?
joe68
09-15-2012, 03:58 PM
well it the bottom of carb, so i say below plates i think, it drove ok this morning but i still feel like it should have more, i try to download a picture but can't fiqure it out, reset timing again, and vacum is back where it should be, on passenger side of carb, i still have a hesatition on start up sometimes, wondering if i should look at plugs , maybe a different one?
mdcamaro
09-15-2012, 07:31 PM
A carb spacer will give you higher RPMs but will take away bottom end. If you run a gear greater than 308 it will help.
A simple timing trick. Bring up the #1 and make sure your timing mark is exactly where you want it with the engine off. Then mark the bottom of the dist with a line on the housing and the intake. Pull the #1 wire off the plug and insert another plug you have laying around, set it on the exhaust manifold so it will ground. Loosen the dist and slowly move it back and forth untill the plug fires. Lock down the dist and check your mark. If the mark is the same your timing was right. Put the wire back on #1.
A simple timing trick. Bring up the #1 and make sure your timing mark is exactly where you want it with the engine off. Then mark the bottom of the dist with a line on the housing and the intake. Pull the #1 wire off the plug and insert another plug you have laying around, set it on the exhaust manifold so it will ground. Loosen the dist and slowly move it back and forth untill the plug fires. Lock down the dist and check your mark. If the mark is the same your timing was right. Put the wire back on #1.
joe68
09-15-2012, 07:58 PM
that is something i never heard! i am going to try that as soon possible, thanks
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i love learning new things
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