Question for clarity on Ignition timing

Val

If anyone can please tell me about how they set the ignition timing in their late 1930s cars. I have been doing it and always set the pointer in the middle between the mark on the fly wheel (as shown in the picture) but I read that  "Timing  is 5 degrees before topdead center. First on flywheel ahead of "U.D.C. 1-6" should register pointer at flywheel inspection hole." 
So AM I to take that as I should put the pointer in line with the mark closest to the U.D.C 1-6 ?  Or is where I have it set acceptable?

Geoff

Set it to the first mark with a timing light at idle.

Val

Geoff, by first mark you mean the one closest to the 1-6?

terraplane8

I like using a vacuum gauge, push its rubber pipe in to the wiper vacuum port on the inlet manifold then adjust the mixture and timing to get the highest reading. For the timing I get the maximum vacuum at idle then back it off a little by up to 1lb. I have got a thread on here from a few years ago discussing that. Works very well. In the old days they road tested and listened for pinging when flooring the throttle at low speed in top, backing off the timing until the sound was no longer heard. After vacuum gauge timing my 212 engine I heard no pinging at all and that is with good compression too, around 7.3:1. I didn't correlate that back to what that then showed on the timing marks, there was no need, but it would be interesting to know nevertheless.

Geoff

The right hand mark, which is the first one that comes into view..

Old Fogey UK

Geoff Moore, the technical guru of the ROC, advises for 8 cylinder engines  that the timing should be set to the maximum advance mark which is 3/4" before top dead centre to cope with modern fuel.
Would our own resident Wise Old Owl (aka Geoff ?) concur with that ?

Old Fogey UK

I forgot  to mention  that the ROC says that 3/4" before TDC means the longer leg of the H mark, i.e. the right leg of the H.

JACK356

Intéressant étant donné que je dois poser le briquet sur mon  34.Ca  fait combien de degrés avant le PMH avec le stroboscope? Merci

ps      8 CYLINDRES

Old Fogey UK

JACK356 said:

Intéressant étant donné que je dois poser le briquet sur mon  34.Ca  fait combien de degrés avant le PMH avec le stroboscope? Merci

ps      8 CYLINDRES

Jacky - I will be timing my engine this way next week and I will send you an email to answer your question.
Cheers, David.

JACK356

Thank you

Val

Thanks all, the good doctor says where I have it is good

Val

Hey Geoff, so to be clear you suggest putting the pointer in which line? Red or blue??

Geoff

The blue line, at idle.   Check that it advances nice and smooth as engine speed increases.

Old Fogey UK

Geoff - did you agree with the advice of the ROC Geoff (see above) ?

Val

Geoff, Even if I am setting it static as car doesn't run at the moment 

Geoff

Old Fogey UK said:

Geoff - did you agree with the advice of the ROC Geoff (see above) ?

Yes, David that is the first mark.  Val, it will fire with this as a static setting, sure.  

Val

Thank you