Anyone have initial timing set higher than 12?

[mrk5]

I was doing some searching on timing here in the forum. I'm curious if anyone is running higher than 12 degrees initial timing. The Demon carb I have recommends 18-24 /forums/images/graemlins/yikes.gif That just seems insane. I know this is going to get a bunch of different opinions, but I'm just curious what they are. /forums/images/graemlins/thinking.gif

 

[sled_dog]

sure it doesn't mean total advance?

 

[slimlynn1]

What are the specs of the engine and carb? I've got mine at about 22 deg.

 

[Beast388]

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The Demon carb I have recommends 18-24 /forums/images/graemlins/yikes.gif That just seems insane.

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Since when does a carb solely determine timing? I wonder why they recommend that? /forums/images/graemlins/dunno.gif /forums/images/graemlins/thinking.gif

There are far too many factors besides a carb that determines timing.......compression ratio, advance curve, cam, octane of gas, engine load etc etc to name a few.

Strange...... /forums/images/graemlins/thinking.gif /forums/images/graemlins/thinking.gif

 

[mrk5]

[ QUOTE ]
Since when does a carb solely determine timing? I wonder why they recommend that? /forums/images/graemlins/dunno.gif /forums/images/graemlins/thinking.gif

There are far too many factors besides a carb that determines timing.......compression ratio, advance curve, cam, octane of gas, engine load etc etc to name a few.

Strange...... /forums/images/graemlins/thinking.gif /forums/images/graemlins/thinking.gif

[/ QUOTE ]

My thoughts exactly.

[ QUOTE ]
What are the specs of the engine and carb? I've got mine at about 22 deg

[/ QUOTE ]

I've got a recently rebuilt (as of 4/30) 350, bored .060, should be close to 9:1 compression, CompCam 268H (.454 lift and 218 duration), Thorley headers, Performer intake, MSD Pro-billet distributor, and 625 Road Demon. Plus living at a higher altitude does allow a little more advance, normally I would run 10-12.

 

[TWISTEDJACK]

Mine likes to run at 30-32 /forums/images/graemlins/dunno.gif

 

[m j]

so at what initial do you start to see problems or power loss?
did you just pull the 12* number from a hat or did you tune to that point?

combustion chamber design and fuel will dictate a bit on timing requirements
better chambers need less advance IIRC

 

[mrk5]

Basically I set it their based on the advice of a mechanic. But the more research I do, the more I find that using one number for all engines is not the best. I plan on using the vacuum method to see how that works. /forums/images/graemlins/thinking.gif

But yeah, basically I set the timing to 12* and tuned the carb to work with that.