How to Choose the Right Size Carburetor

Want to know how to select the right size carburetor? Is it some magic formula or do you need an old guy to choose what's right for you? How many CFM do you need? Should you go bigger? Lets go through it and find out the best way to choose one.

#edelbrock #holley #carburetor

[robpeters]

Thank you for such an informative video!
I’ve been telling guys since the early 80’s that you have to spec your components for what you want out of it.
They always said bigger is always bigger and you have to chrome it, etc.
I’ve grown up trucking in my blood with the family business. Every truck is different and has to be spec’s out for different applications. If you spec it wrong, it will not be able to do what it was intended for and you can’t make money from it. It will end up costing you more money just to operate if at all.
You explained it very well. You have to first figure out what you want out of it and go from there.
That is why so many guys go and buy that dream car and end up crashing it moments after picking it up. You have to know what the vehicle is capable of doing and what you are capable of doing also. Once you get all the parts of the equation down, you will have a near perfect machine!
I say near perfect because we are never satisfied once you start down this road. lol!
Thanks!

[mattbauckman]

Even before seeing this, I believe most guys have too much carburetor on their engine. 750 cfm seems to be the default carb everyone uses, but I chose a 600 cfm for my bone stock 396 325 hp big block. The street manners and throttle response are impressive, better than any of my injected engines in fact. I've had many guys tell me I need a 750, that a 600 is too small etc. but nope.

[chestrockwell]

Few weeks ago Brian helped me work through picking the proper fuel delivery for a project I'm working on; very nice and knowledgeable guy. Thanks again Brian.

[williamhenderson]

I just let your video audio Play in the shop when I’m working and not in the mood for music. It’s great background noise that also refreshes knowledge

[AreaThirteenThirteen]

I had a '77 Camaro back in the mid to late 80's that had a .40 over 350 with flat top pistons, roller rockers, stock exhaust manifolds a TH-350 trans, stock converter with 3:08 rear gears and 305 two barrel heads with small ports and an RV type camshaft ( I don't remember the brand name or specs on it though) that had an almost stock idle but you could tell it wasn't completely stock, the intake was a dual plane Edelbrock performer and I put on a 600 Holley with vacuum secondaries. I dont remember if the Edelbrock carburetors were around yet but the Holley was just over $100 brand new back then. I never had to fool with the jets or anything other than the idle speed and mixture, it ran pretty well out of the box. I ended up daily driving that car for quite some time. I had to watch the fuel quality and timing since the 305 heads bumped up the compression a bit but it had excellent throttle response and averaged around 17 MPG on the highway. I'm sure the cam, heads and exhaust held back any real top end performance but the low end torque was good enough for what I used the car for since it rarely saw anything over 4-5K RPM. I still regret selling it along with the other old cars I used to have which were cheap and plentiful back then.

[cliffpeerson]

When towing or using engine in a heavy vehicle go smaller CFM. Air Velocity is what we are after in carburetor sizing. We want high air velocity so the carburetor works properly plus to fill the cylinders well especially at low rpms. If air velocity falls off due to carburetor being to big low end suffers. That's why smaller for towing and heavy vehicles. You can go bigger with lighter vehicles and higher rpms engines. When driving on the street we don't see much past 3500 rpms so the high air velocity of a smaller carburetor provides a much better driving experience. Good stuff!

[stuckinmygarage]

I just had an "Ah-ha!" moment at @16:10 . It took me a couple runs through your other good videos. U never know what you missed when you don't understand stuff. Thank you, again!

[Ratridez]

I'm running a junkyard low compression dodge 360, edelbrock 340 manifold, A body manifolds true dual in a 3300 lb car and 373 diff with a edelbrock 600 cfm, mostly in town driving . Runs great, amazing fuel mileage and spark plugs are a light brown .

[Reece_]

thanks for clearing alot of this up, I have been looking for a Holley DP for my 466 BBF in my 78 f100 street/strip truck (mostly street realistically), have been concerned about going to little or wasting time over carbureting

[rjgenua]

Man iv follow you. I got a 350. 1972 Monte. It's a cruiser. But she likes to go fast. I put the fuel just like you I'm sitting at 5000 in Colorado. Adjustments made according to the chart. Still runs rich rich

[thewoodsman]

Great video by the way very informative for people such as myself.

My truck has a 700r4 tranny and the axel gear ratio is unknown at the moment.

[robertclymer]

Great info as usual! Appreciate all the knowledge you share with the car community, it really really helps!! Thank you and cheers from Motown. Oh, new subscriber and hit the bell.

[williamhenderson]

Lol, here I am again listening to your videos. Just put all the side markers in my Mach 1. A tie rod end. And adjusted my reverse band all while listening to these

[ernestadamsjr.]

Just ran across this video. It was VERY informative. Here is my dilemma: I have a stock 350 sbc in a 72 Impala coupe (weighs about 3900 lbs.) with a 200R4 transmission and 3.73 rear end. An Edelbrock 1406 (600 cfm) sits atop a dual plane intake manifold that is fed by in-tank pump (max psi: 49-50) regulated to 5.5 psi by an AER fuel regulator. Max RPM for the engine is 5500; however, I have yet to hit 4000 even on the hills in my locale (3800 was the highest so far). I do not race but use the 3.73 gears for acceleration and the 200's OD to cruise. The 1406, IMO, burns too much gas. Edelbrock recommends the 1406; however, an older mechanic I know suggested moving to the 1404 (500 cfm). The math in your video also supports that mechanic. I'm looking for a final confirmation prior to spending the money for a new carb.

[rolandsgarage]

So glad I stumbled across this. I'm building a 351w for a 92 f150 4x4 AOD transmission. I'm running a .513 lift 270/276 duration 110 lobe separation roller cam. Stock Gt40 heads with a spring kit an edelbrock performer intake. Motor will be natural aspiration. Cam is rated 1500- 5500 rpm and intake is idle - 5500. It will be a daily driver and toy hauler. I have an edelbrock 1405 600 cfm sitting my shop now, but im wondering if I should step up to one of the new avs 650 cfm. Great content btw.

[MarianoLu]

If anybody is wondering the 3456 comes from converting cubic inches to cubic feet and from considering that the car is 4 stroke meaning you will only pull air every other rotation.

[b-wingman]

Thanks so much for the info . I have a 460 that I want to put an Edlebrock carb on .

[heinzmichels]

Thx for the vid!
Do you think a stock 351 Windsor 2 barrel will benefit from the "big" Autolite 2100 from a 2 barrel 390?
It's one venturi size above the stock carb.
Stock cam street driven, FMX auto.
It ist more about fiddeling around and finding the sweet spot set up for the car.

[michionwheels]

Q-jets use the airdoor to tune the cfm.Everyone of them has at least the 750cfm potential i.e. of some rare buicktypes. The factory used the angle of the airdoor for setting the carbs to tamer or smaller engines

[jrsgarage]

Dual plane uses 1/2 carb, single plane runs whole carb Major difference 🚩🚩👍