440 power gains/ aluminum head advantages?

NoahSewal said

yes that makes sense. i'll try that tomorrow. now that there's better weather where im at i can spend all day after work messing with it ha. would the vacuum return back to normal once its sitting at 3k (as if i were cruising at 3k) or does it stay dropped until you let of the pedal? i feel like i've noticed my vacuum only dropping initially on wot then once the engine catches up with how far the carb is open it comes back up to around 15-20 pounds until i let off. because in that case i think my cruising would suffer due to too much advance (34 mechanical plus whatever my vacuum advance would be)

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At idle or part throttle the vacuum advance will be activated. Won't hurt a thing at part throttle as it's not under load. But don't forget, you're going to have to limit the total mechanical advance to around 34 degrees (without the vacuum can hooked up) to keep spark knock at bay. So you're going to have to either weld the slots up in the distributor and refile them to a specific length to give the proper advance, OR run one of the FBO limiter plates. There have been a lot of people complaining on a very recent thread about those plates advancing too much, including myself. That's why I recommend choosing a total advance and welding and refiling the slots.