OpticalIlyushin
Junior Member
- Joined
- Jun 29, 2022
- Posts
- 1
- Reaction score
- 0
- Location
- Oregon
- First Name
- Clint
- Truck Year
- 1980
- Truck Model
- C20
- Engine Size
- 292
As the title suggests, I've recently picked up a 1980 C20 with the 292 straight six. It is really feeble, I doubt it is over 90hp. The issues are it has very little power and backfires through the carburetor if I open the throttle too much(unless I have the initial timing way advanced), and I've been driving myself nuts trying to figure it out. If I have the timing way too advanced at idle (backfires when you try to start it, idles rough) it will have a bit more power but still not enough. For whatever reason it came with a points distributor and I was thinking maybe something was haywire in it, so I got a new HEI unit(coil and everything) since that's what it's supposed to have anyways. Compression varies from 148-162 PSI, the spark plugs are new and gapped at .035". Timing is at 8° BTDC (yes I know factory is 6° but it idles nicer at 8°), and the harmonic balancer matches what the piston is doing. It pulls 19" of vacuum at an idle and so far as I can tell has no vacuum leaks. The engine has been switched over to a 2bbl Weber 32/36, I've cleaned it in an ultrasonic cleaner and rebuilt it (power valve/accelerator pump/gaskets) and gone through the tuning process.
At this point I'm not sure where to proceed, any ideas would be appreciated.
At this point I'm not sure where to proceed, any ideas would be appreciated.