Timing my 72

[Jfwh1tt]

Howdy! I'm new to the forums here. I've just been looking and using this for lots of research. I am the proud new owner of 72 LWB fleetside. It will certainly be a project. I looks good now, but there are a lot of hidden things to clean up. It runs OK at idle, but really needs to be fine tuned, which is why I'm here. The truck has a 350, but it is not the original motor, or so I've been told. Correcting the timing would be simple, but the last dude who put the motor in left the timing indicator off the engine. While researching this, I found someone mentioned another method. Have you guys ever heard of this, and is it an acceptable way to set the timing?

"There is a different way to time your engine, and that is with a vacuum gauge. Here is how you do it, find the vacuum port that has vacuum at all times(that is called manifold vacuum) the other is ported vacuum which only has vacuum after you start to open the thottle plates, anyway, put a vacuum gauge on the manifold vacuum and plug the vacuum hose going to the vacuum advance. start the engine and let it idle and ck the vacuum, now turn the distributor either way a very small amount until your vacuum reading changes, if vacuum goes down on the gauge turn distributor other way. Keep turning the distributor until you get max vacuum and adjust the carb idle as you do this to keep rpm around 800-900 max. The goal is to get the highest vacuum reading as possible. If the timing is advance to far vacuum will be low also if retarded to much vacuum will be low. If the engine pings on acceleration after this exercise then retard the timing until it stops. It is little time consuming this way but you will get the maximum timing you can depending on your compression ratio, cam and fuel quality."

Thanks,
John