If it doesn't make it to near zero, the carb is too small.

I just thought he would run out of gas.

@Dakota Bethune If I recall, if more than 3" vacuum, larger carb can help. Of couse it hurts nothing except power to run small carb, mileage might be better with smaller bores (my reason to prefer spread bore 4bbl design, better low speed vaporization).

@@thisisyourcaptainspeaking2259 Love the spread bores with vacuum secondary!

@@thisisyourcaptainspeaking2259 Ahh man, and I just hours ago removed the double pumper from my engine for a much smaller carb. Wish I tried this for a look see before hand. Ahh well.

Thunderhead289 is pretty detailed on vacuum gauge and AFR meter tuning for cruise and power too.

@Rob. Nick and his family are very wealthy and his rich buddies also, its also expensive Canadian gas,,5$ a Gallon is normal,,that gas comes from Saudi arabia by boat its expensive and dumb as Canada has massive reserves in oil.

If it opens, you're out of the "economy" range lol

Or the cam was so big, it couldn't open!

SmiteTeamSix so true. I was fortunate to have grown up with a bunch of friends and we were all muscle car gearheads with cars of various brands, values etc. One of the guys had one of those Chevelle’s and it was a very cool car. Camero had a short run of that cowl system as well in the ealy 80’s.

71-73 Mustangs had them on the hood, but facing the opposite direction. You'd need granny riding on the hood looking in the scoops and giving you a thumbs up or down to know if you were in economy mode.

JC Whitney's Used to Sell Interior Mount one With A Special Settable MPG Dial using Micro Screwdriver. I loved Mine Installed on Brothers,73 Satellite Sebring Plus with Hopped Small Block

I don't know if that's the most efficient way, haha. That just means you need the least air to get the most RPM, and that usually ends up being richer than being most efficient.

I remember as a kid my dad knew an old mechanic that had a sun brand “engine analyzer” that had vacuum gauges, dwell meter, an oscilloscope and a few other things. Of course at the time I didn’t know what any of that was for and remember thinking with all those wires and tubes you’d think you’d see it in a hospital ICU, not a garage 😂

@Konstantinos Palaiologos True, but dwell and timing affects all this also. In order, if you have points, get the dwell set correctly, then get the timing close . Once those are done, then you can adjust the carb mixture screw(s) for best vacuum, then typically give 'em a half turn or so back towards "rich" just to help with drivability. Lastly, after all that other stuff is set and done, adjust your idle speed and you're done. (PS - I also use the vacuum gauge to help determine best timing on non-stock engines, but that's an "advanced" course in Shadetree 101 :-) ). -Ed on the Ridge

@Konstantinos Palaiologos he told you the problem, you are drawing air into the engine that's not going through the carb. You can ditch the pcv, and have it run right. Replace the breather with a plug, or plumb it's port into the manifold, and have it run right. Or, continue letting it pull atmosphere into the engine via the crankcase vents and not run right.

Idle mixture can be set using vacuum or RPM both work equally well. What's VERY important that most people miss however is that for a vehicle with an automatic transmission those adjustments need to be made in gear. Where idle tuning and a vacuum gauge really come into their own is tuning timing. We should be adjusting idle timing for peak vacuum, however that really only works in the long run with the distributor vacuum connected to manifold vacuum which few know how to tune anymore.

@Motersickle Bum you make a good point, I hardly see bumper stickers at all

My wife was a "fluctuator". It used to drive me crazy riding around while she drove

Jimmy Joedailey vvvvrrrrrrroooooommmmmmmmvvvvrrrrrroooooommmmmmm. And the pedal went down with every point she was trying to make, and coasted in between thoughts. Yea, drives me crazy too.

@Mike B easy does it is alcoholics anonymouses slogan

@@hex374 Yep, Live and let Live. KiSS. Many good ones to live by.

there is a video of a person rebuilding a engine with out hot tanking the engine the engine lasted 15 min. the video is of nick dyno tuning someone's engine for them

@@jeffrey4547 I've put stuff together without tanking. But did spend a lot on brake clean. A lot depends on how long the things been sitting with shit in it.

@@needmetal3221 use a steam cleaner i even steam clean it after hot tank u would be surprise on how much stuff come out of a engine but i have over hauled engines too as long as it has not set for long

Hot tank does not clean oil-galleys. There is a whole lot more to that story. Tony definitely got a bad rap on that. I'm not in any way placing blame. Not at all. If any blame belongs on Tony's shoulders? It was the basic idea in the first place! That job was doomed from go simply because of the time-line. The scope of work needed more than one day. Bad idea. That part might be Tony's fault. But, Lunar absolutely did not follow through with his end of the bargain. That block/crank was supposed to show up assembly clean. It was nowhere near assembly clean. So, the chowder in the brew Nick discovered belongs on Lunar's shoulders if anybody. Just a bad deal all around. You absolutely do not need a hot tank. I have built countless (well, probably 30~40) engines that never saw a hot tank, and provided many tens of thousands of miles of service after completion. With the time-line they had, they didn't even have enough time for cleaning, let alone the whole build! Hell, I built a 318 in a 1981 Ramcharger plow-truck that broke a crank in half in 1994. I took that engine and 3 other cores. Mixed and matched the best parts from all 4 engines. New rings/bearings/gaskets was the extent of the new parts. That engine, in that same truck, still plows my Dad's neighborhood to this day. Hot tank is NOT necessary. Cleanliness certainly is though!

What, like if you push the gas less, less gas goes into your engine????

Nathan Brame how to use the vacuum gauge for tuning....nice try

@@fastinradfordable perfect rendition of a millenial thinking out loud

My uncle had a ‘65 SS Impala with a huge vacuum gauge on the dash by the passenger’s side. Very Cool!

funny you mention it, not only do i remember those gauges in Pontiacs (used to own a Goat), but recently had to rent a Uhaul...GMC, Ls engine, and right on the dash was, you guessed it...a mileage gauge added by Uhaul. And it was about as useful as you remember :) every hill i just ignored it--like a box is going to do well in wind.

@@albertgaspar627 LOL Yeah, the first one I ever saw was on a 1985 Chevy Caprice. It was a big ol' 4 door yacht with a little 305. The gauge stayed on the green side when idling but as soon as you even touched the throttle it would peg out to the red!

@Motersickle Bum Yeah, people who were savvy had been driving economically for decades before that, but with the "gas crisis" of the late 70s more people became aware of it, so they started putting the gauges in for the dummies who didn't already know how to drive.

Motersickle Bum That shit drives me crazy. My old lady has a cvt I keep telling her she will kill it. The transmission costs $7000....

Economy gauges and "upshift" idiot lights on stick shift cars. For those who don't understand how a car operates. And I never understood racing to a stoplight or sign. Then again, I find that people drive the way they live their lives. Either they are looking "down the road" and into the future, planning now for what's up ahead....or they're racing from problem to problem.

I turned 50 the other day and if you can take a little advice ,if you intend to make a career out of cars dont be "a GM guy" , be a mechanic, look at all cars,bikes,trucks ,all machinery as just nuts and bolts to not limit your choices for jobs. I started as a motorcycle mechanic but as time went on i found out the pay sucked compared to what my heavy industry mates were on so did another apprenticeship and now fix fighter jets on much better pay and fiddle with japanese ,british, italian bikes and australian and american cars on weekends. Its all nuts and bolts.

@@watsisbuttndo829 I do like to tinker with other vehicles too I like all sorts of cars i just really like gm but I do understand where you are coming from and on the account that you have years of experience I'll happily take your advice thanks

@@ExpWars i was "a ford guy" at your age and living in Australia a xb falcon coupe (think mad max interceptor) was always the goal. But in my shed at the moment is a 65 pontiac gto. Its natural to have a favorite but get into everything and make sure you research pay rates and job opportunities if this is your thing, good luck young fellow!.

@@watsisbuttndo829 of course I also like hondas believe it or not, and Subarus

How do you know you are a GM guy if you haven't experienced the other cars?

I don't think so. I think this is done to avoid triggering the enrichment circuit in the carburetor. In a modern car you want to accelerate quickly up to speed and then cruise in a high gear.

@@SinsBird carb & efi both have enrichment circuits. One is mechanical and the other done with the ECM. On speed density setups it monitors engine vacuum via the MAP sensor (a vacuum guage), and adjusts enrichment based on vacuum level. Cars with a MAF sensor measure air flow to approximate engine load & vacuum. Using this data to adjust enrichment. So yes, it's the same concept with modern engines. Drive in a manner that maintains the highest vacuum, and the engine management system will have an easier time maintaining max MPG. Of course, sometimes there's more to life then good MPG. Lol

Many things play an important roll in the name of fuel economy...many of which people completely overlook. *An awesome vehicle alignment is crucial: the Toe-in & toe-out, along with its camber angles, *Disc brakes: will work/ out perform drum brakes- HOWEVER: a vehicle with All four corners having a drum brake setup (if dialed in correctly) WILL have less rolling resistance than any vehicle equipped with Disc (disc front/drum rear, &/or if the vehicle has disc on all four corners)- the All four corner drum brakes will have less roll resistance & aids in better fuel mpg’s, *air pressure & tire size(s) play a bigger roll than people think. *the aerodynamics/ the shape of the cars (plus the aid of wing windows: when opened to help guide air around the side door glass windows that might be open too- helps air to flow quicker past the vehicle, *of course the engine, carb, & it’s “performance parts play a huge roll in fuel economy... & the driver itself.... obviously a lead footer will get next to no fuel mpg’s when compared to somebody who’s driving like they got a head full of common sense & simple logic.... dont go trouncing on it from stoplights to stoplights.... a lil common sense goes a long way. I’m sure Tony could spend months on describing & making countless videos of each one of these topics explaining the importance of each of these categories.

Cool car. I just sold my '64 300 Silver Special coupe h/top. 383. Is yours Canadian?

My first car was 64 Saratoga with a vacuum guage on console. Shut us some pics....Mr. Lucky.

@@moyadapne968 yes it is and its a 2 door 383 1090 built that year

@@raygarant9370 ty ty and i will post some pics we are trying to figure out how we want to do the rebuild low numbers car we want it to be a touring car . the hubby and i want to make the brakes more up to date but keep the rest original such a sexy looking car

@@CrochetRevolution sounds good, get the brakes up to snuff, maybe find a police/towing package suspension set up (perhaps a sway bar and brakes and transmission upgrades) to make it more highway friendly. The old Mopar Action magazines used to get into this, plus how to get the steering box to be more responsive--no more sawing away at the steering wheel as she wanders down the road.

i'm the same way with tools. Estate sales and whatnot tend to have the older tools that don't have all the modern doodads like a coffee maker and internet access, but they're built solid. And if you ever need that tool for any reason, you'll wonder why the heck you didn't pay a dollar for it back then.

Albert Gaspar - Yes, when someone's dad dies and there's a yard sale you sadly pay pennies on the dollar for top quality tools that the man took great pride in using yet the son has no skills or desire to use them. He just wants to get a couple of bucks to purchase another flat screen TV. Sad.

True--I just picked up one today, still in the vacuum packaging. I learned at my first estate sale, look for the LL Bean and Craftsman tool stuff, even if it was broken, you could return them and get new stuff. Tho I think LL Bean ditched their lifetime warantee recently. But its why I hate someone cutting up a classic just to make a Pro-Touring car out of it. We like to think we "own" something, but we're really just care takers for it. It all goes to someone else someday. As for the kid who doesn't know what they have, its how a friend got his 1957 Chevy 210 wagon--his sister had first crack at "grandad's boat" and she didn't like the manual steering nor the three on the tree.