Timing is everything....right!

So i have read much in the way of timing on these forums but am still a bit confused about it.

 I understand that i am to disconnect my vacum and run up my rpm's until my mech. timing is all in (as early as possible without pinging) It is a 383 stroker and i wish to achieve 36 deg total advance.(I THINK!...any advive on this would be appreciated) When setting my full in with my vac disconnected i am to subtract my initial timing....here is where my question lies. Is the number that i subtract my "total vacum advance" or the degrees that my engine is running at idle with the vac dissconnected. I assume it is the total vac but how do i decide what that number should be if i am starting from scratch? Where should my car idle and what do i want my initial timing to be at (degrees,RPM)?

Any Advice on where to go to correctly step by step set my timing would be appreciated.

I would also like to add something from my experience for others.

I put timing tape my first 383 stroker and it came off so i only had a limited chance to set my timing...then i resorted to the common "set it till it doesn't ping" type method. Not always a good idea....my car is somewhat but not too loud and even though i could not hear it...the car was detonating. Now we could discuss in length for much time as to why my first attempt at a 383 stroker came apart in the worst way (chunks breaking off the top of the piston (over the Pin section) but i have been though it. Now it is back to blowing a whack more money and i will leave nothing to chance. Living is learning.    

 I would just like to suggest that if people want to do it right and are spending the money    it is a good idea to get a balancer cover (summit $29) and a good light and do whatever it takes to get the right information to SET YOUR TIMING RIGHT

Reading this forum if definitely a good start.


Thanks in advance for the help and time reading this and thanks in the past for help i have already recieved.


"Why do i like Corvettes?"

"Cause they are shaped like a beautiful woman and handle like an angry tiger"


Al  

When you disconnect your VACUUM you Accelerate the engine until the Centrifical Advance is full on.  Should occur at or around 3 grand.(Anywhere from 24 to almost 46 BTC) read your timing at that number and see what it is.  Then to that you are going to then see what your vehicle reads at idle ( from probably 8 - 12 BTC)Subtract the idle Timing from the total timing and you have the mechanical timing that your weights and springs allow in the Centrifical class.  On Most Chevy engines I hook the Vacuum advance to the low port(Hardly any vaccuum at idle and plenty on the top end vacuum)  

Now I have a vaccuum source and I read what the timing is again at 3ooo RPM.  Whatever that number is is a combination of my mechanical(centrifical) and my Vaccuum advance.  your initial timing is always going to be Before Top Dead Center (BTC 8 - 12) so you want to adjust your mechanical(Centrifical) by way of weights and springs(Or Electronic is inside of your distributor and generaly the distributor manufacturer supplies a crib sheet) or your you get an adjustable Vaccuum advance(Into which you may insert a jewlers screwdriver into the vacuum port your vaccuum line hooks up to on the Distributor, and with one guy holding the light and accelerator and watching the tack to keep it at 3 grand you turn the screwdriver to adjust the vaccum side to set it at what the difference between the mechanical and the vaccuum has to be to achieve a total of 38 degrees.

If it were mine I would try to keep the total at 35 BTC with Octane Ratings what they are.

RedCorvette86

Sorry about doing this twice.  I turned the wrong screw somewhere.  
Corvette's Should only come in "Torch Red" (U1U)

When you disconnect your VACUUM you Accelerate the engine until the Centrifical Advance is full on.  Should occur at or around 3 grand.(Anywhere from 24 to almost 46 BTC) read your timing at that number and see what it is.  Then to that you are going to then see what your vehicle reads at idle ( from probably 8 - 12 BTC)Subtract the idle Timing from the total timing and you have the mechanical timing that your weights and springs allow in the Centrifical class.  On Most Chevy engines I hook the Vacuum advance to the low port(Hardly any vaccuum at idle and plenty on the top end vacuum)  

Now I have a vaccuum source and I read what the timing is again at 3ooo RPM.  Whatever that number is is a combination of my mechanical(centrifical) and my Vaccuum advance.  your initial timing is always going to be Before Top Dead Center (BTC 8 - 12) so you want to adjust your mechanical(Centrifical) by way of weights and springs(Or Electronic is inside of your distributor and generaly the distributor manufacturer supplies a crib sheet) or your you get an adjustable Vaccuum advance(Into which you may insert a jewlers screwdriver into the vacuum port your vaccuum line hooks up to on the Distributor, and with one guy holding the light and accelerator and watching the tack to keep it at 3 grand you turn the screwdriver to adjust the vaccum side to set it at what the difference between the mechanical and the vaccuum has to be to achieve a total of 38 degrees.

If it were mine I would try to keep the total at 35 BTC with Octane Ratings what they are.

RedCorvette86  
Corvette's Should only come in "Torch Red" (U1U)