TIMING ? AGAIN
08-17-2009, 02:21 PM
#43
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Location: Belleville, IL
Posts: 658
Originally Posted by JEFF69Z28
Originally Posted by OneBadGMC
No, you're not under carbed.
Can you make a video and upload it? What you call rough and what I call rough may be two different things.
Some carbs run rough at part throttle. I know you said it was a gas motor, so it's not the typical alky roughness at part throttle. You didn't say, however, whether the motor has power valves in it, or if the power valves are plugged off. If there are no power valves, it will run rough at part throttle.
If, however, you can back off the motor 2 degrees, and the 'roughness' goes away, then you may want to try closing up plug gaps to like .018 (just to try it), then up the timing.
If the roughness still occurs, it's time to start changing out electronic parts until you find the culprit.
It could be:
1. cap, rotor, or both.
2. Old plug wires? Have you checked the resistance in each plug wire with an ohm meter?
3. Coil going bad
4. Points in the dist? If points, have you checked the point gap?
5. 6AL box going bad.
6. Excessive plug gap
7. Bad ground... The coil should be grounded to the battery and heads (both heads) via dedicated leads.
Those are all things off the top of my head that can cause 'roughness' due to ignition issues. This is assuming that there's nothing wrong with the carb.
A simpler thing to try would be changing the carb out...
Can you make a video and upload it? What you call rough and what I call rough may be two different things.
Some carbs run rough at part throttle. I know you said it was a gas motor, so it's not the typical alky roughness at part throttle. You didn't say, however, whether the motor has power valves in it, or if the power valves are plugged off. If there are no power valves, it will run rough at part throttle.
If, however, you can back off the motor 2 degrees, and the 'roughness' goes away, then you may want to try closing up plug gaps to like .018 (just to try it), then up the timing.
If the roughness still occurs, it's time to start changing out electronic parts until you find the culprit.
It could be:
1. cap, rotor, or both.
2. Old plug wires? Have you checked the resistance in each plug wire with an ohm meter?
3. Coil going bad
4. Points in the dist? If points, have you checked the point gap?
5. 6AL box going bad.
6. Excessive plug gap
7. Bad ground... The coil should be grounded to the battery and heads (both heads) via dedicated leads.
Those are all things off the top of my head that can cause 'roughness' due to ignition issues. This is assuming that there's nothing wrong with the carb.
A simpler thing to try would be changing the carb out...
ALSO I WANT TO THANK EVERYONE FOR THEIR TIME AND HELP.MY CAPS LOCK BUTTON IS BROKE ON MY KEYBOARD THAT IS WHY IM TYPING IN CAP'S.
08-17-2009, 03:24 PM
#44
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Thread Starter
Join Date: Apr 2008
Posts: 496
IT CLEANS UP WHEN IT LAUNCHES AT THE TRACK THEN STARTS MISSING RIGHT BEFORE I SHIFT INTO 2ND GEAR CLEANS UP AGAIN THEN MISSES RIGHT BEFORE I SHIFT INTO 3RD GEAR THEN MISSES UNTIL I LET OFF THE GAS AT THE END OF THE 1/4 MILE,I HAVE THE LOW REV SET AT 7500 AND THE HIGH REV SET AT 7500 ON THE 6AL2 BOX,I DONT USE THE LOW REV OPTION AT ALL,IM SHIFTING AT 7000 RPM,CAR RAN 10.55,56&60.
08-17-2009, 03:27 PM
#45
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Thread Starter
Join Date: Apr 2008
Posts: 496
Originally Posted by montecarlo84
is the coil mounted stright up or leaning on it's side?
I had a blaster 2 on the side and my car was a dog
moved it stright up and was fine.
I had a blaster 2 on the side and my car was a dog
moved it stright up and was fine.
08-17-2009, 03:55 PM
#46
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Join Date: Mar 2008
Location: New Orleans,La
Posts: 515
you may need to swap dist. box. coil,with known good parts 1 at a time from a friend or something
or bring it to a preformance ignition place to have it checked
if it checks out good you'll need to look in other places
don't get stuck in one problem. valve float may sound the same.
pull on all the wires tite'en up lose stuff.
try shiffing at 6800 or 6500 to see if it runs through
or bring it to a preformance ignition place to have it checked
if it checks out good you'll need to look in other places
don't get stuck in one problem. valve float may sound the same.
pull on all the wires tite'en up lose stuff.
try shiffing at 6800 or 6500 to see if it runs through
08-17-2009, 04:02 PM
#48
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Join Date: Feb 2007
Location: Michigan
Posts: 1,900
Originally Posted by Tod74
I didn't read every post but are the valve springs good?
08-17-2009, 04:41 PM
#50
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Join Date: Sep 2007
Location: Belleville, IL
Posts: 658
New doesn't matter too much if they are the wrong springs. What exact spring brand/part number is in it?
If the springs wind up being correct, then as said before, you're gonna have to either take it somewhere to be checked, or start swapping out parts one at a time until you find the culprit.
If the springs wind up being correct, then as said before, you're gonna have to either take it somewhere to be checked, or start swapping out parts one at a time until you find the culprit.