Help Me Pass Some Gas

[MDJEEPER]

So, I did a vacuum test on my Jeep project this morning...It's running about 21 inches of vacuum at idle, but drops to about 16 inches around 3500 RPM. This is a sure sign (I think) of a partially plugged exhaust system, and maybe why my Jeep loses power under load.

Seeing as how it's the 4th of July weekend and I won't have new exhaust parts until later next week...Does anybody have a temporary fix that will give a little backpressure relief while allowing the Jeep to still be driveable??

P.S. Should add that I don't know where the blockage might be right now, but both the converter and muffler are very old, and could even be original...

 

[BusaDave9]

The jeeps didn't have very good catalytic converters in the '80s. Air had to go through honeycomb shaped holes. These cats would clog up. I had that problem on my '82 CJ7 . I removed my cat and fixed it with a pry bar and a large hammer. It's a very delicate procedure but for legal reasons I won't go into the details. It made a world of difference and ran much better.
The reason I found out that my cat was clogged was I had an exhaust leak at the manifold and when I fixed that my engine would not even start.

 

[priceg]

16 inches at 3500 is good. Keep looking

 

[MDJEEPER]

16 inches at 3500 is good. Keep looking

Hmm...I thought that if the vacuum dropped (and stays) below idle level as RPM increases then there is an exhaust restriction? Are you saying that a drop from 21 to 16 is not a big enough drop??

Also, the vacuum gage I'm using may not be exactly accurate (but close). Is there another test I could perform to confirm or rule out an exhaust restriction since the low number is close to 16?