Technical timing a early small block ford

so.... I have scoured Google, Bing, youTube, etc and have found very little good info on setting timing on a early Ford 302. Lots of general tips, but all vague at best. Here is what I found....

set timing to 6 degrees BTDC or.... set timing to 15 degrees BTDC (whaaa..... seriously, who is right???)

I have a relatively stock early 302, but have a 4bbl, headers and turbo mufflers with dual exhaust (no cross over).

Do I want 6, 8, 10, 14. 18..... geesh! You cannot get a solid answer. If I had a SBC, I could find a MILLION answers, videos, blogs, forums, etc. but you'd think that the SBF community is keeping a secret

Also.... do I time with the vacuum line attached or disconnected????
- I just ordered a new carb so I can eliminate that as an issue
- I have new plugs, wires, cap and rotor
- with the new carb installed, where do I set the timing
(and do I do it with the vacuum line connected to the distributor or not)?

Thoughts?

 

Echlin tune up specs 1984, initial timing set at 6 deg btdc @ 575 rpm no vac adv connected. Total vac adv 10 deg @ 20 in vacuum, total centrifugal adv 13 deg @ 2500 rpm. Be sure to check the advance totals one at a time as fords distributors would wear out the stop block in the vacuum advance and old ones would over advance. This adds up to a total advance of 29 degrees @ 2500 rpm. most ford dampeners only had a scale to 30 degrees. it's good to make a mark at 40 with a white pen. Or use a dynamic timing light so you can read the timing directly off the light readout. We always add 4 degrees to the initial here because of altitude, that don't apply to you in Seattle.

 

These specs were for a 1971 Ford 302. You didn't say how early.

 

Sbf's like a little advance, so I simply advance the distributor until the car cranks real slow and then I retard it just a tad so it cranks normally. Maybe not scientific, but it has always worked well for me that way. I've played with timing lights and they seem to verify that what I do puts it pretty close to being right on.

Don

 

all great advice, I have a new carb on order and expect it will solve most of my issues. Wil post an update once installed this week.

 

There you go. Like Don said sbf's like a little advance. The 331 in my wagon runs at 12 degrees initial, with a total advance of 46 @ 3000 rpm. (HEI distributor) So you have some room to play around.

 

Yep, they like advance... 10-12 at idle, vac disconnected is where I almost always ended up. Do look at the mechanical advance; some of the later distributors had quite a bit less total advance and slow curves, reworking the springs/stops can pay dividends...