Motor Timing Question

[ZoomingM3]

I have a question regarding setting the timing on my 70 El Camino. I have a 1968 Block (396 cu in), 325 HP with 1969 (L-34) Oval Port Heads.

I want to be sure I'm setting the timing correctly so with this in mind, can someone please tell me what the following timing settings should be?

Ignition timing @ engine idle degrees BTDC

Centrifugal advance crank degrees @ engine RPM

Vacuum advance crank degrees

Note, I'm running a MSD Distributor, MSD-6A Ignition System and Turbo 400 Transmission.

Thanks for any help/information you can provide.

[skiman762]

bigger the cam higher the degrees at idle
centri 36 in by 2500 rpm
total vacum 42-44 watch for pinging

[ZoomingM3]

Skiman762,

Thanks for the info. I have a stock cam, should I be setting the idle timing at 4 degrees BTDC? With regard to setting the vacuum setting, what should the vacuum pressure be at 42-44?

Thanks again for your help.

[skiman762]

Originally Posted by ZoomingM3

Skiman762,

Thanks for the info. I have a stock cam, should I be setting the idle timing at 4 degrees BTDC? With regard to setting the vacuum setting, what should the vacuum pressure be at 42-44?

Thanks again for your help.

You don't really need to worry about the vacuum at cruise it's more important at idle 14-16 for a healthy motor don't worry if it's not in that range just be sure it steady
As far as 4 degrees you can run more (better throttle response) you could get away with 8-12 as long as it starts good just remember what ever you move at idle everything moves up the same number so you will have to reduce it across the board. Timing is the key to allot of engine wows don’t be afraid to play with it till you find what you car likes just keep the total in check so you don’t hurt anything.
I always disconnect and plug my vacuum till I have the base and centrifugal set up
you may need an adjustable vacuum can to set that part once you have you base and total centrifugal set all you do is take the total 36 degees from the total vacuum you want say 42 degrees you will want 6 degees plus the base say 10 =16 with the car at idle plug in the vacuum and you should have 16 at the crank if not adjust accordingly