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 Post subject: Timing
 Post Posted: Thu Jun 08, 2006 10:43 am 
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Hi,

If one has to pull out a few degrees of timing is it better to pull some static timing or limit the amount of mechanical advance? Thanks, Jeff

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 Post subject: Re: Timing
 Post Posted: Thu Jun 08, 2006 11:07 am 
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Margaritaman wrote:
Hi, If one has to pull out a few degrees of timing is it better to pull some static timing or limit the amount of mechanical advance? Thanks, Jeff


your idle quality after you pull the needed amount out will tell you which way you need to go. If persay you need to take out 4* out of your total and you go from 14* to 10* at idle and all is still well then your OK, but if the engine doesnt like to idle w/ just 10* then you'll need to bump it back up and limit the total advance.


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 Post subject: Re: Timing
 Post Posted: Thu Jun 08, 2006 1:09 pm 
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DCarr wrote:
Margaritaman wrote:
Hi, If one has to pull out a few degrees of timing is it better to pull some static timing or limit the amount of mechanical advance? Thanks, Jeff


your idle quality after you pull the needed amount out will tell you which way you need to go. If persay you need to take out 4* out of your total and you go from 14* to 10* at idle and all is still well then your OK, but if the engine doesnt like to idle w/ just 10* then you'll need to bump it back up and limit the total advance.
good response. that is what i would do. \:D/

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 Post Posted: Thu Jun 08, 2006 1:57 pm 
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thanks guys. I ended up just replacing the bushing to limit the mechanical to 18*. 37* total. I have an MSD 6BTM that retards under boost so I can dial it back more if need be. 40* was too much even with the retard and the plugs were confirming that.

It's really amazing to me how much you can really feel the difference the closer you get to the correct tune.

Now I'm going to back down the squirters a bit, get rid of the minor hesitation, and whammo. Oh ya, right after the new fuel pump!

thanks, MM

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 Post Posted: Thu Jun 08, 2006 2:04 pm 
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Talking about timing. I've run small blocks forever. My first street performance SBC was a 331 with 2.02 heads, GM Z28 intake and a vacuum secondary 780 Holley. Back then I ran 40 degrees total. It was a stick shift car with 4:88s so it never did get a chance to be "lugged" around as I usually had my foot in it! \:D/

Then, I built a 406 SBC for that first Camaro I had. Timing again was at 40 degrees on that engine until a friend told me that he had dynoed a similar engine and that it liked 35 degrees on the dyno. Well, I backed up the total timing to 35 degrees and the car did run quicker and faster off the lower total timing. I run 34 degrees on this SBC stroker I have now and have set it as low as 32 degrees in the past.

Yup, ya just have to play with them a little to see what they like! Kinda like the old lady, hey! =; \:D/

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 Post Posted: Thu Jun 08, 2006 3:20 pm 
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Ken0069 wrote:
Yup, ya just have to play with them a little to see what they like


Thats it exactly. I generally start off at 36* and go up 2* at a time until the MPH falls off then I go back 2-4*

All the 350 based combo's I had in my 64 ended up with 41-43*. At 35 - 38* it would be like driving the family station wagon full of kids and groceries. I blame on it the amount of piston dome the flame had to deal with. Smaller domes and flat tops definetly get away with a less timing.


MM .... 40* w/ forced induction would make me nervous !!! How much boost do you make and how much timing does the box take out per lb or otherwise ?


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 Post Posted: Thu Jun 08, 2006 5:39 pm 
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DCarr wrote:
MM .... 40* w/ forced induction would make me nervous !!! How much boost do you make and how much timing does the box take out per lb or otherwise ?


0-3 degrees per pound of boost. Running 10 lbs. I check the plugs after every run becuase I sure as heck coldn't hear it ratlle if I wanted to! It seems to be happy at 28* with boost retarded. I'll gladly give up a few hp instead of having to replace a piston.

MM

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