Small Block & Big Block Chevy Specific - engine timing for nitrous?

Ok ive read the sticky "nitrous faq" sticky.i want to know if you pull base timing out of the engine or do it with the vaccum advance disconnected and pull the advance timing back some? im doing it on a carbed small block 350 10:1 compression,mild cam and single plane intake with a 100 shot for starters

well what timing are you running on the motor already?

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It's been a long long time since I had vac adv. IIRC, I would take 4 from base & tune down from there.
I never adjusted timing with vac hooked up, plug it while adjusting. Good luck.

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for every 50 take 2 deg off of timing.. put play it safe.. go a little more and dyno it to make sure.

Well, i have removed the vacuum to check time, and i have also left it, but on my cammed motors, the vacuum makes nothing at RPM at all, on a mild to stock motor, it might be different, it might still pull vacuum. Just do it with the vac line removed, as stated, about 4 deg for every 100 HP.

Thanks for the help guys....yeah mrdragster1970 ive heard of alot of ppl not running a vacc advance line....what doest that actually do for the engine perfomance wise?

Nothing, it eerly helps fuel economy under partial throttle, giving a bit of advance when you step into it slightly to cruise to higher speeds. At WOT there is 0 vacuum to make it function, so a race car doesnt need one.

so would it help me any to un hook it or should i leave it hooked up with the nitrous?

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I'm a big fan of locked timing, no vac, no mech. I do everything with timers, relays & chips.
I want my stuff rock solid & stable. Consistent every pass. Good luck.

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leave the vac. adv. off and set ur timing at 3000 rpm with that setup i would go with just about 34 degress if running a 100 shot and go from there

Are you saying 34 total and then retard it 4 more for the 100 shot or 34 with the 100 shot figured in?