I'll try to keep it short, cause this problem has already gone a long way, and is taking too much of my time ... 
My engine has started misfiring and backfiring for a few months now.
So far I've changed :
- new carb, Holley 500cfm, 2bbl ( didn't change a thing)
- new fuel pump, filter, fuel lines (no change)
- all new ignition system. (distri, coil, sparks, cables, the works)
- new exhaust, H-pipe, flowmaster mufflers
The new ignition system was a huge improvement. With the old distri, no matter at what timing I'ed set it, it would always run like crap. I tried with a new distri, missfiring was gone, and the engine idled just fine.
But while driving the engine started to run bad, like it was only running on 4 cyl.
It would do it for a few seconds, and go away.
But since yesterday, it got worse, now it's always like that, (nothing has changed on the engine)
So today I figured that I'ed give the old carb a try again, maybe there's something wrong with the new one.
Under the carb is a carb spacer, that I've never removed before, the previous owner 'glued' it on the upper intake.
My dad told me to remove the spacer, I gave him a funny look, what could a carb spacer be doing wrong ?
Being older and all, and supposed to be wiser than me
, I listened to my dad, and removed the spacer.
Now here's the wierd part, there are 3 holes in the intake ???
You can clearly see the 2 normal ones, and then there's this small extra hole on the upper left side.
What's it doing there ??? My carb spacer was blocking it, so the old nor the new carb had any access to it.
If you look closely you can see that are traces of burned dirt in the extra hole, like you would get on an exhaust.
I had a look at the bottom of the old carb, and indeed, the bottom of the carb had the same black burned color. So the old carb used to have a connection I guess with the third hole.
Maybe the previous owner decided to install another carb spacer ?
pics : Pic 1 , Pic 2
But what is that extra hole for, what does it do ?
And could that be the problem that I can't get the engine running right ?
Who can solve my mistery ?
thank's in advance,
Phil M.
My engine has started misfiring and backfiring for a few months now.
So far I've changed :
- new carb, Holley 500cfm, 2bbl ( didn't change a thing)
- new fuel pump, filter, fuel lines (no change)
- all new ignition system. (distri, coil, sparks, cables, the works)
- new exhaust, H-pipe, flowmaster mufflers
The new ignition system was a huge improvement. With the old distri, no matter at what timing I'ed set it, it would always run like crap. I tried with a new distri, missfiring was gone, and the engine idled just fine.
But while driving the engine started to run bad, like it was only running on 4 cyl.
It would do it for a few seconds, and go away.
But since yesterday, it got worse, now it's always like that, (nothing has changed on the engine)
So today I figured that I'ed give the old carb a try again, maybe there's something wrong with the new one.
Under the carb is a carb spacer, that I've never removed before, the previous owner 'glued' it on the upper intake.
My dad told me to remove the spacer, I gave him a funny look, what could a carb spacer be doing wrong ?
Being older and all, and supposed to be wiser than me
, I listened to my dad, and removed the spacer.Now here's the wierd part, there are 3 holes in the intake ???
You can clearly see the 2 normal ones, and then there's this small extra hole on the upper left side.
What's it doing there ??? My carb spacer was blocking it, so the old nor the new carb had any access to it.
If you look closely you can see that are traces of burned dirt in the extra hole, like you would get on an exhaust.
I had a look at the bottom of the old carb, and indeed, the bottom of the carb had the same black burned color. So the old carb used to have a connection I guess with the third hole.
Maybe the previous owner decided to install another carb spacer ?
pics : Pic 1 , Pic 2
But what is that extra hole for, what does it do ?
And could that be the problem that I can't get the engine running right ?
Who can solve my mistery ?
thank's in advance,
Phil M.
