Stagger jetting question

318willrun said

Either way, I don't get the concept. Not saying it doesn't work, just say'n I don't understand how a cylinder knows to pull from one throttle plate where the jetting is XX and not the other throttle plate which is XX jetting.... when all 4 throttle plates are exposed on an open plenum to every cylinder.

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We have o2s on each bank and egts for each cyl. on our dyno. This does not hold true 100% of the time but generally motors with poor fuel distribution can have wide splits from side to side on the o2s. Also wide variation on egt temps. Generally low temps represent cylinders with more fuel and high temps cylinders with less fuel. If you can move the fuel to even the distribution generally you will be rewarded with one or more of the following: smoother running engine, more HP , a more tuneable engine, lower bsfc numbers, less split side to side on O2s, more even exhaust temps.
Some techniques I have used and things that I have found that can affect Fuel distribution are: Twisting boosters, bending boosters, notching boosters, changing type of booster, staggered jetting, adding spacers, sliding spacers, removing spacers,changing carburetors, changing air cleaner base or top. Just to name a few. I have seen some of these tricks change a motor with an audible miss to a motor that doesn't skip a beat. It's good day at the dyno when that happens. Don't make the assumption that just because you have an open plenum to draw from that all cylinders are going to get the same amount of fuel. I say fuel but air would apply also. It's just that fuel is much fussier. It has more mass so it's harder to change directions and it is hard to get and then keep it atomized. As soon as air slows down somewhere fuel wants to drop out and puddle. It's hard to get it reatomized after that happens.