Good point, I was going to bring that up when I posted about the coil but forgot. Very much related.
Need a liittle help from the higher ups
- Thread starter Jridge1
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Remember it could be the pipe next to manifold also if it is double wall and collapsed ,so don't count those out.If ok then muffler most likely ,never saw a tail pipe collapsed but you never know.
I am not sure on that ,but I have seen one collapsed.
I can give you a suggestion only if you want to try this. If it bogs setting in garage at 3000 rpm steady or a little above take a rag and hold to each tailpipe and see if you notice a difference in exhaust coming out in volume. If that show that would tell you which side . At that point I would replace both side exhaust anyway.
Yes but you are not holding at 5800 so a short burst won't bring in bog,and of course you don't want to hold at that rpm setting in garage.
Right. Im just going to take it to the shop tomorrow and take the exhaust off all the way. I think you may have it. I remember years ago my dad took his van to a muffler shop and they put a 2" muffler in place of the 3" muffler he originally had and it did about the same thing. The only difference was on the van (350 wyed into a single exhaust) it sounded really forceful like something was stuck in the tail pipe. The impala doesn't sound like that maybe because the dual exhaust? I don't know but we'll find out tomorrow
I googled walker pipes and they say the pipe are double wall. So original may not be .
If you are not showing any pressure on the vacuum gauge when you go to WOT you do not have a exhaust blockage.
Yes this problem is what prompted the rebuild of the carb fuel pump and ignition. Tried process of elimination but nothing eliminated the problem thus far
Interesting to see if taking off the exhaust does it. I haven't spent a lot of time troubleshooting for a while, but it seems strange that under no-load she RPM's right up and when under a load only 3k. Maybe disconnecting the pipes will do it. If not I would be installing a fuel pressure gauge, unless I missed reading that you've tried that.
You're working very hard at this. Don't take any thing for granted. More than once I have mistaken an ignition problem for a fuel problem or visa versa.
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Wrong,,,,,if you had pressure carb would be blowing gas out of carb.I can't post from phone ,but Google a vacuum test for blocked exhaust,and it shows vacuum decrease and holding decrease trying to accelerate.