timing question

[charger01]

May be a dumb question, but on initial timing of my 440.  I Know I need to plug off the vacuum advance on the distributor, but do I also plug of the port on the carb?  Iam assuming you do all your timing at idle approx 800 rpm?  thanks in advance

[Al]

yes plug off the vacuum port at the carb

[b5blue]

Plug the carb port, just leave the Dist. vac. nipple "open" no need to plug it.  You know the vac. is adjustable by putting an allen wrench in the nipple hole right? (If needed.)

[Chryco Psycho]

in most cases I really recommend not using the V A or atleast minimizing it with an allen wrench
it will run best with 14-16* initial timing and a 20-24* curve peaking at 36-38*

[bobs66440]

it will run best with 14-16* initial timing and a 20-24* curve peaking at 36-38*

14-16*?  I have always heard 10-12* That's what mine is set at (12). Is 14-16 common for a 440?

[flyinlow]

Timing at idle is not as important as total timing (base + centrifical) in the 34-38* range. I run 24* BTDC at idle + 12* centrifical for 36* total on a mild Eddy head 446. Plus 8* vacuum advance. Run as much base timing as you can with the vacuum going up and still being able to start it with a warm engine. And of course no knocking.

[charger01]

I thought I read 7 1/2 btc for basic timing. Is this not correct.  Kinda unsure where to set this thing at.  It is a 69 440 hp pretty much stock.

[flyinlow]

Sorry, for the confusion. For stock timing , disconnect the vacuum line and plug it. At idle there is probably not any vaccum in this hose, but plug it just as a precaution. Golf tee's or and old spark plug work great. You don't need to cap off the carb nipple if you plug the vacuum advance hose at the distributor end. Then set the timing at the desired number, 7.5* BTDC in your case at the specified warmed up idle speed. 800 rpm is fine.

[firefighter3931]

Even with a bone stock engine it will respond favorably to increased base timing at idle. 

I'd start at 14* BTDC and tune from there 



Ron

[RGA]

Base timing is 10-12 degrees, go up 1 degree for every thousand feet of elevation. This is what I have always done. Also there should be no vacum to the distributor at idle. It is designed to apply vacum when you accelerate to advance the spark.  But the timing can change with different cams, also when there is slack in the timing chain due to wear.

[elacruze]

I just spent a bunch of time and a little money with Don Gould at FBO systems, and after much discussion and some negotiating he sent me this;

16* static timing
18* mechanical in @3200rpm
14* vacuum timing @14+"

10.6:1 compression, closed chamber, .027" quench
238* cam duration @.050", 110*LSA and 107* intake lobe centerline
14-16" vacuum @850rpm

It is just magnificent.

I trusted him as an acknowledge expert and he did not disappoint.