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kman67rsss
10-03-2004, 10:45 AM
i have an complete msd set up, and am curious as to what i should run for timing. the motor is a 414 bbc with 11:1 cr, a 236/242 612/612 lift cam demon 850 carb, aluminum heads, and will be run on 93 octane pump gas. any help would be great.

also when first installing the dist. whats the proper way. is #1 cylinder supposed to be a TDC? and line up the rotor with it or how is it done?

Zefhix
10-03-2004, 11:00 AM
i have an complete msd set up, and am curious as to what i should run for timing. the motor is a 414 bbc with 11:1 cr, a 236/242 612/612 lift cam demon 850 carb, aluminum heads, and will be run on 93 octane pump gas. any help would be great.

also when first installing the dist. whats the proper way. is #1 cylinder supposed to be a TDC? and line up the rotor with it or how is it done?

If it's a N/A car I would say best thing is to set total timing at 32* and tune from there. Every motor likes something different. Yes, set the #1 BTDC (preferably with a guage to correct the timing tab if it's off). If you can't, then line the harmonic balancer timing mark with the 0 on the timing tab. Drop the distributor so the rotor points to the #1 cylinder on the distributor. Voila. Watch for the fireball......j/k.
:cool:

kman67rsss
10-06-2004, 01:29 PM
yes its a N/A car. the MSD dist i have is set at 28*. will that be ok to try out for now?

Zefhix
10-09-2004, 01:23 PM
Sorry, didn't realize you posted a reply. You say you're MSD has 28* timing...I assume that means it has 28* of mechanical advance set into it. That will be fine to start the car but regardless you want to make sure that you set your total timing once the car is running to 32* and see how it runs after you break it in. Bear in mind that means you will only have 4* (w/out vacumn) of initial so most likely your setup will want more depending on your cam/heads/....etc. Take it slow 2 degrees at a time with 91/92 octane until the car detonates then back it off two degrees. Like I said, it's tough because every car likes something different but you should be good. :cool:

My427stang
10-16-2004, 12:54 PM
If you have 28 in the distributor. Drop the dist in and set inital timing to 8 degrees BTDC. Most of the cool headed (alum) rats I do like 36 total (8+28) without vac advance

More important to pinging is your timing curve, for a street car motor look for total timing all in by 2700, for a truck with the same motor or a heavy highway geared car, go all in by 3000

With as much .050 duration you shouldnt have a detonation problem, if you do, odds are you are too lean. However dont go chasing mixture or timing if you dont know your advance curve. Basically 8 initial with 28 in the curve is close enough to perfect, if it pings 1st problem could be the timing curve, 2nd would be mixture not the other way

Finally, an out of the box MSD has a pitifully slow curve, so if you drop it in and it doesnt ping, good, next step is to shape the curve properly and the motor will run much better, MUCH better

If you cant tell by my rambling, the advance curve is probably one of the most important tuning tools, more than total or initial timing, and probably more than jetting if the jetting is close