Brake booster hose is 11/32" and special thickness to avoid being sucked shut and restricting vacuum to the booster--some had a charcoal canister in line to absorb fuel vapors in hopes of prolonging booster diaphram life too..
Most vacuum gauges have a 3/16" or 1/4" hose connection,but also come with a funnel shaped adapter fitting to allow it to be used on larger diameter hoses...the brake booster can be connected to the intake fitting thats in your pictures,it matters not where its connected, as long as its to manifold vacuum source,and the stock hookup is directly above that under the carb's throttle butterflies..no reason why a "T" cant be used and one side blocked off,just be sure to use a good method of blocking it off so the brake booster wont lose vacuum..
Running with a vacuum leak like that could burn a valve or cause pinging,if left that way too long.....at extreme higher altitudes the leaner mixture may actually make it seem to run better however,but re-jetting the carb and having no vacuum leaks is the way to go..
The way to use the gauge to set the carb & timing is to first set the timing to stock specs,then adjust the carb idle mixture screws to obtain the highest and steadiest needle readings on the gauge--some engines will show as much as 18 to 22 inches of vacuum when tuned properly,others with a hi performance camshaft wont show much over 15 or even less,and will be harder to get a steady reading from..
I have found the timing can often be advanced some by up to several degrees over the stock settings without the engine protesting by pinging under a load ,or cranking hard during hot starts..that will improve gas mileage and power to some degree..
Most vacuum gauges have a 3/16" or 1/4" hose connection,but also come with a funnel shaped adapter fitting to allow it to be used on larger diameter hoses...the brake booster can be connected to the intake fitting thats in your pictures,it matters not where its connected, as long as its to manifold vacuum source,and the stock hookup is directly above that under the carb's throttle butterflies..no reason why a "T" cant be used and one side blocked off,just be sure to use a good method of blocking it off so the brake booster wont lose vacuum..
Running with a vacuum leak like that could burn a valve or cause pinging,if left that way too long.....at extreme higher altitudes the leaner mixture may actually make it seem to run better however,but re-jetting the carb and having no vacuum leaks is the way to go..
The way to use the gauge to set the carb & timing is to first set the timing to stock specs,then adjust the carb idle mixture screws to obtain the highest and steadiest needle readings on the gauge--some engines will show as much as 18 to 22 inches of vacuum when tuned properly,others with a hi performance camshaft wont show much over 15 or even less,and will be harder to get a steady reading from..
I have found the timing can often be advanced some by up to several degrees over the stock settings without the engine protesting by pinging under a load ,or cranking hard during hot starts..that will improve gas mileage and power to some degree..
