Timing Question

[aero3113]

I set the gap on my points and timed the engine with a timing light about a month ago,car ran good. Today I borrowed a vacuum gauge from a friend (was curious). I hooked up the vacuum gauge and ran the engine.The needle was in the red which said late timing. I loosened the distributor and rotated it to get the highest reading on the gauge (around 18-20). I took the car out for a drive and noticed what I think is spark knock. What is the correct way to time a 218?

Edited April 24, 2010 by aero3113

[Merle Coggins]

What is the correct way to time a 218?

In my opinion... with a timing light.

[Reg Evans]

I would just rotate the dist. back just enough to get rid of the spark knock.

[aero3113]

Do you think I should time it with the light and use the vacuum gauge at the same time? Get the highest vacuum reading closest to TDC?

[greg g]

Use the vacuum gauge and back it off till the ping goes away. Todays gas isn;t the same stuff it was 60 years ago. Timing at TDC is basically retarded with todays fuel formulas. has a way slower flame front these days and needs more anticipation. I set mine withthe vacuum gauge and found I needed to back off a bit, when I checked it withthe light it was at 6 before. No ping, runs great, starts easy, plugs are nice and tan.

[aero3113]

Thanks Greg,I will try that when I get a chance. What do you think the vacuum gauge should read? I did back it off a little bit today,but still had a ping. Could it be possible I can be in the red on the gauge for a correct adjustment?

[greg g]

Where did you hook the gauge, should be intake manifold, at idle. should be 18 to 21 inches for a stock engine, ie single carb, stock cam profile.

http://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm

[aero3113]

The wiper port

[aero3113]

Great link Greg,thanks