My 327 has been backfiring when I torque brake. Nothing real loud, just a pop, but it's getting annoying not being able to flesh out the problem.
The timing is fine and it runs like a champ. I even rolled the timing back and forth a touch just to see if there was any affect, and there was none.
It doesn't do this any time except decelerating in gear. Any suggestions?
I know this has to be a simple fix, right?
-- lab~rat >:-) The less you care, the more it doesn't matter.
Sounds like an exhaust lobe is wearing on the cam!
Common problem, sorry to say. But that's one ot the early signs.
Refinish King
Do you have a Rochester quadra-Bog on it??? My buddy had the same problem. Think it was a bad plunger in the carb. In any case, check the carb. You have too much fuel going to the engine, for sure.
On Tue, 9 Nov 2004 20:19:27 -0800, "James Alio" puked:
Edelbrock. Same solution?
-- lab~rat >:-) The less you care, the more it doesn't matter.
When the accelerator pump dries or shrinks:
It's usually the other way around. Too little or sporadic fuel spray on acceleration.
Refinish King
On Wed, 10 Nov 2004 16:50:14 GMT, "Refinish_King1" puked:
But I have NO symptom other than the pop. It idles smooth and accelerates like a charm. And it started over night.
-- lab~rat >:-) The less you care, the more it doesn't matter.
Look for:
A loose exhaust rocker, an exhaust valve that doesn't open as much as the others. If you have points and condenser, look for a high dwell, simulating retarded timing. Maybe from not greasing the rubbing block on the points?
Refinish King
On Thu, 11 Nov 2004 01:46:04 GMT, "Refinish King" puked:
I'll look for an exhaust rocker, good point. I have a pointless setup now...
Thanks.
-- lab~rat >:-) The less you care, the more it doesn't matter.
Do you have an exhaust leak either on the pipes or at the manifolds? On the over-run when you step off the loud pedal, unburnt fuel will ignite in the exhausts with air drawn in through any exhaust leaks and hence your pops.
I had it on my 400 Pontiac - I discovered I had poorly sealing / damaged gaskets at the centre exhaust joints on my headers. A set of good copper header gaskets solved the pops.
My pleasure!
Refinish King
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