Thread: how long can I limp along a low compression engine?

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Got my 67 GMC out of storage and am getting it back on the road. I don't want to put a new engine in til I get the body work and paint sorted out, which will probably be a couple years. In the meantime, I'd like to have it running and drivable.

It runs ok, but backfires out the carb when romping on it off idle. It's a sbc 283 with about 100k miles. It was rebuilt in 1980 or so and has been in the truck ever since. I don't have details on the build anymore (bought the motor from a friend who rolled his 66 chevelle right after having the motor rebuilt). I think it was a pretty stock rebuild, but recall that he might have put in a mild cam. It had a quadrajet, but I replaced that with a used Edeldbrock 500 a couple weeks ago. The QJet never ran that smooth, so I hoped the Edelbrock would be better. The carb change has made little difference. The engine has smoked out the exhaust pipes (not to bad) and smoked out the crankcase vent (pretty bad) for the last 10k miles or more.

I checked the compression and got the following: left bank 115/130/120/85, right bank 95/100/90/100. When I squirted some oil in the low cylinders, the compression when up on average 10 psi.

Can a tired engine run somewhat smooth and reliable for a year or two while I work on the paint and body? I'll only drive it maybe 1000 miles a year or so, but want it reliable enough to drive 100 miles at a time. I'm thinking of putting HEI, but is that just polishing a turd?

Thanks for any ideas/advice.