Engine Timing for a D42 flathead

[SteveR]

I have a 1937 Plymouth P4 with a D42  flathead 6, I believe that gives her a 1952 engine. She has new electronic ignition and been converted to 12 Volt. Could someone tell me what the proper timing and RPM should be?

[Adam H P15 D30]

I set mine until it pinged and backed it off a couple of degrees.  Ended up about 5 deg BTDC.  You didn't mention what electronic conversion you have, if you converted your old distributor make sure the vacuum advance can is not leaking.

 

Adam

Edited September 20, 2018 by Adam H P15 D30

[SteveR]

Thanks Adam for your reply. I am not sure what electronic conversion I have. I have just bought the car and the person I purchased it from did the converting. At what RPM were you running when you did the timing? Also which side is the timing marks on? I presume the driver side but its hard to see on this car.

[Adam H P15 D30]

If it’s a stock distributor it’s probably a Pertronix, check the vacuum advance. 

I timed mine at about 500 rpm. You are correct, marks are hard to see. I painted mine red to see better. 

[SteveR]

Adam, Thanks for the photo. I went to have another look at the timing marks. The wind was blowing quite briskly and as I had my head in the engine the wind ........... You guessed it Those hood doors are heavy! Oddly I didn't get a bump but it was enough to say that's enough for today. :o)

[Jolly]

I thought I’ve read that adjusting timing is best by using a vacuum gauge. Need to use the port on the intake manifold. That worked for me on my ‘40 rebuild.