Originally Posted by Phil_F_NM

I used to do a lot of acoustic work when I was in the Navy and these days when I'm doing manual camera repair, I use acoustic means to time shutters. A few years ago, I used a combination of acoustic recording and scan lines from a CRT to time a 4x5 focal plane shutter in a Speed Graphic camera. I got the speeds accurate to within 1/30 of a stop which is far more accurate than most mechanical cameras. And the camera body was produced in 1953, so age doesn't matter.

But I digress, my apologies.

Wouldn't it be a similar procedure to acoustically isolate the #1 injector line from the other lines by removing the clips that bind them together, then using a pickup, record or live-feed the acoustic signal of the #1 line and the injector popping to very accurately find out how the IP is timed? Of course there is the issue of "freezing" the motion of the crankshaft optically through use of a strobe like a gasser timing light. It can be done but I'm thinking it would take a bit of gear and a bunch of patience.

All that work-around seems easier to me using gear that I know well, vice the counting of drips. Maybe it's just me thinking around this in an odd way.

Through this last few months of owning my '78 300D I've wondered things like this and how I could get around not having spark plugs to measure signal off of. I'd just have to create my own signal somehow and I'm thinking that acoustically timing the IP would not only be extraordinarly accurate, it would be just plain neat. When I get to a place where I have a garage at my disposal (in a month or so) I'll give it a try and post the results here.

Phil Forrest