Since GM used spreadbore 4-barrels, the 2-barrel was often bigger than the primaries on the 4-barrels. If you never got into the secondaries on your 4-barrel, you might think the 2-barrel seemed more powerful around town.

@bendeleted9155

2 ай бұрын

9:15 perfectly stated by Adam later in the video.

@catsaregovernmentspies

2 ай бұрын

Yes, until the late 70s when GM released the Dualjet with the same sized bores as the primaries on their Quadrajet.

@tholmes2169

2 ай бұрын

But a Quadrajet would get better mileage exactly for that same reason, if you stayed out of the secondaries. My 350 Buick was factory with the 2 Barrel but I found a 70 350/4 off a LeSabre and took the intake and carb. I was getting 20 to 22 mpg on the freeway when commuting back to and forth to college in the 90s.

@michaelbenardo5695

2 ай бұрын

That's why I prefer square bores.

@Sheisthedevilyouknowwho-ft9we

2 ай бұрын

Yeah, I remember when I finally found this out, that if you didn't floor it, and open the secondaries, you can get better mileage with the quadrajet than the dual jet. (We had a dual jet here that was a quadrajet with the secondaries covered with a metal plate and it said dualjet on top 😂 it's been so long I don't recall how common those were). I don't recall what car it was, what rear diff ratio, onexof the writers at HPP with a 455 4 bbl years ago said you can get 20 mpg if you drive it the way he does. I was born '74, but I was the last of 6. My father only drove Pontiacs, and bought many used ones for my older siblings to drive. Bonnevilles, Grand Villes mostly. A few years after the 301 came out, he spent the next decade buying cheap used cars, some had 301s like my moms 77 Bonn or 77 GP for sis, but if it was a huge older Bonn or GV he put the 2.90 rear in it with a 301 he'd get somewhere for the good mileage. We might still have 3 301s here. When I learned this about the 2 bbl vs 4 bbl (I could have been learning so much from him 1980 through the 90s working on these '70s Pontiac but I wasn't interested at a young age), I wish I had known well enough to tell dad "no, don't ditch ths 455 or 400 again, you , me, mom, or the others, can drive gently, and get good mileage, just stay out of the secondaries". Just blow the carbon out on the 2 mile spur once in a while like they used to say. When I told other gearheads years later how many 455s and 400s my dad gave away for a song in the early 80s and later😫 they were like why ? He fell in love with the 301. I became more interested in working on my own cars later in life, and see some of this stuff that he did back then like why..why..why..(they had a 63 Bonn with a 4 speed , he took it out and put an automatic in it cause mom was huge, pregnant 😂, she said she loved driving that 389 4 bbl with the 4 speed before he thought he needed to change it). My uncle & my mom said he did a lot of unnecessary work on the countless Pontiacs he owned, but what the heck, you live and you learn. Mss you dad

The essential purpose of the 2bbl big blocks was low end torque using oversized jetting. GM realized customer test drives were at low speeds where bottom end torque mattered most.

@salninethousand2496

2 ай бұрын

Also, 2bbl = improved throttle response off idle and lower RPMs.

@JW...-oj5iw

2 ай бұрын

The Quadrajet gave excellent throttle response at the bottom end for those willing to learn how to work the throttle judiciously. Getting the engine to medium RPM before engaging the huge secondaries results in strong transition to full power. A competent carb tuner can balance a Quadrajet to eliminate the Quadrabog reputation. My most recent engine build included a Competition Cams 292 and a Weiand Team G intake along with a Quadrajet and a nice HEI sparker. Given that combination, the torque leapt up at midrange RPM and rotated the axle nose up. That was unforeseen and required some refitting and bolstering. That combo was just a bit too much for streetability and I had to retire that car. Now it's been replaced with a bone stock C-20 in the longest factory configuration for 1975.

@dmandman9

2 ай бұрын

Often the 2 barrel carbs got lower fuel economy than the 4 barrels when operated under normal conditions.

@empireOfLove2

2 ай бұрын

@@dmandman9 Larger venturis for the same volumetric air flow always result in worse fuel economy, slower air velocity promotes less complete air/fuel mixing. See ThunderHead289, he put a lawnmower carburetor (with a very tiny venturi) on a ford 302 and got amazing fuel economy.

@michaelbenardo5695

2 ай бұрын

Unless you used those huge secondaries a lot.

I know a guy I met in the early 90s. He was building a hot rod 455 for his car. In the mean time, his family car blew its engine, it was a mid 70s Buick station wagon full size. He had no choice but to put his hot rod engine in that wagon. He embarrassed all rice modifiers who challenged him.

@JW...-oj5iw

2 ай бұрын

Our neighbors had a T-Bucket powered by a Caddy engine. I wish it and they were still around.

@JW...-oj5iw

2 ай бұрын

I built up my 350 in my '75 K-20 and it was a screamer. The truck was equipped with the granny 4 speed and manual transfer case. Those gear cases accounted for an incredible traffic clearing incident. I was working at a service station when a big truck hauling a big load stalled on the street in front of the station. Traffic got jammed up and the local police arrived to try to manage the mess, but that truck rig wasn't about to move. I had some experience with the 4wd truck and so I offered to pull the rig out of the street. I hooked my chain to the truck's front axle my rear frame. I engaged my front hubs and began to try to pull in 4 wheel high range with the transmission in first gear. The load was too heavy and my truck sat there pulling on the chain and bouncing up and down. After a couple seconds, I realized I needed lower gearing and shifted the transfer case to 4 wheel low range. At that point the power pulled the truck, trailer and tractor from the street and into the open parking lot where I could figure out what was wrong with the truck. Corrosion on the battery cables. Always remember to wash it off with blue window cleaner and protect it with original WD-40. BTW, I became a towing driver subsequently. I've cleaned a lot of battery clamps in my life. I know what works best.

@scrocrates6380

2 ай бұрын

I'm sorry honey....I had no choice 😂

The best thing about cars of that era is you could buy a 2 barrel, single exhaust car for decent money. Then convert it to a 4 barrel and dual exhaust later. Modern vehicles are pretty much as is. There's no modifications you can do to them to change the performance. Unless you have the money to add or upgrade turbos and have the computer programmed. Not much you can do in your driveway. This is why I never want a modern vehicle. They're all overly complicated, cookie cutter crossovers with too much unnecessary technology

@jamesengland7461

2 ай бұрын

They're not as hard as you think to modify, but then they're not so sandbagged that just a dual exhaust adds 50hp either. You can still swap a cam on an LS or Hemi just like old times.

@embiggens1

2 ай бұрын

I think there's two sides there. With modern, forced induction cars, you can get huge gains with just a tune, no hardware necessary. I picked up over 70hp with nothing but a tune. A gain that big used to require a lot of hard parts. I do miss the old, inefficient engines with so much untapped potential, but it's not all bad these days. Yet, anyway.

@michaelbenardo5695

2 ай бұрын

Not only that, if you DO find a way to modify a modern car, it won't pass smog.

@dwightvoeks9970

2 ай бұрын

All you have to do is throw a tune on modern cars and some you can instantly gain 100hp and better fuel economy.

@tabbott429

2 ай бұрын

I bought a gryphon programmer for my 2006 F150 4x4 long ago 375$ It was tuned professionally by them and i just plugged it in and reprogrammed the computer with a couple clicks. I gained 2-3 mpg (100 miles more per fillup) and a MUCH better/responsive driving experience. Shift points and timing were optimized and made the stock tune feel pathetic.

Yeah 99.9% of the time the secondaries are closed. I used to find Qjets with stuck secondary butterflies from lack of use surprisingly often. lol

@curtjeziorski350

2 ай бұрын

True. If Those secondary butterflys were not shiny ass clean that means they weren't used enough!

@cigarsgunsandgasoline8032

Ай бұрын

We called em Quarda-bogs around here... mine actually performed decently, because I drove it like a madman!

I remember racing my buddy in his 1968 olds455 and I in my ‘79 trans am 403/auto. I couldn’t shake him !

@dansmusic5749

2 ай бұрын

Both Olds engines.

@DaveSoCal

2 ай бұрын

@@dansmusic5749 yeah but I was in a Trans Am not a 4 door land yatch 😭

@DeepseaSteve

2 ай бұрын

Had a 77 with the 403. Ok for cruising but no race engine

@dansmusic5749

2 ай бұрын

@@DaveSoCal More detuning from smog controls, I assume.

@michaelbenardo5695

2 ай бұрын

60s cars were rocket fast. 70s cars were not much better than late 40s cars.

I always enjoy these engine episodes, Adam. Keep 'em coming, please!

With those big heavy beasts, torque is the name of the game. HP is fine for top speed, but torque gets you off the line. Nobody was racing those sedans with the 2BBLs, but acceleration was fine for Interstates, and as you said, zippy around town. I've driven plenty of Quadrajets, and love them to death, but Rochester's 'Duojets' were special too.

@madmike2624

2 ай бұрын

I could not agree more!!! Great idle and wide-open sound with the air cleaner flipped, it had a great sound!!

@paulfrantizek102

2 ай бұрын

A 2V Big Block has good low end torque and good throttle response. In most applications, that's enough.

@jimmyaber5920

2 ай бұрын

I commuted until recently around the north side of DFW area. There were loads of 420 hp escalades, bmw x5m, mercedes gl 63 amg, etc. with much more than 420hp and for the mostmpart they were only using 35hpnto go slow in the left lane while on the phone. Definitely the 2 bbl big block buyer.

@jameswaltersdorf2783

2 ай бұрын

We had a 68 Delta 88 when I was growing up, and it's incredible now to think how powerful that engine was. What I don't remember was having to use premium gasoline. Was that because regular gasoline was leaded or higher octane generally? We had the car until I graduated from high school in 79 and I know they started using unleaded gasoline, so I don't know if we ruined the engine or something. One thing about 60s Oldsmobiles was you could always tell that one was nearby because the exhaust had a particular, lovely throaty timbre.

@dermotthompson2115

2 ай бұрын

Nah. Why throw away useful power for no good reason?

The 455 c.i. With 365hp in my 1970 442 4sp convertible was quite fun. Wish I still had it!

@opera93

2 ай бұрын

Yes, thanks…. Interestingly, I opted to a 1970 DOdge CORONET 500//383/ DUAL , AUTO./ no AIR Conditioning ,@$3100.00…….( switching from FORD, as Dealer could not give “ test Drives” for BOSS MUSTANG: passing on a70 Challenger Triple Green/ 4 SPD/Se RT/ Loaded every option((my baby BROTHER remembers vividly)

@Mike-jv4rz

Ай бұрын

Worth a small fortune now ...

Also of note, the 2bbl engines usually had a smaller cam and heads/valves, which also accentuates lower RPM response.

@madmike2624

2 ай бұрын

great point!!!

By 1974, you could get the "economy" 455, touting 9 MPG instead of 8. 😂

@sergioleone3583

2 ай бұрын

Well, it was a 12.5% increase in economy! ;-)

@larrynorsworthy8582

2 ай бұрын

😂

@salninethousand2496

2 ай бұрын

That's 12.5% better fuel economy, which is actually quite good.

@towgod7985

2 ай бұрын

9mpg @ $3.55 gal. MOTHER that hurts!

@towgod7985

2 ай бұрын

@@salninethousand2496 ROFL!

Back in the 70's when I was a teenager, the shop I worked at had a 68 Pontiac Catalina with a 400 2bbl, and a 67 Olds Delmont high compression 425 2bbl we used for parts runs and delivering customers. They did awesome burnouts 😁 Especially the Olds with the open differential. From a stop the right rear tire would spin up so fast it only took a couple seconds to shift in to 2nd and keep on going!

@marcanthony854

2 ай бұрын

I miss those days!

@izzydizzy1115

2 ай бұрын

I can still see the smoke from you burnouts!

@jamesgibson5876

2 ай бұрын

​@silasakron4692 do you realize Quadra jets only had two cfm ..all q jets ..either 750 or 800

I remember my first experience new car shopping with my father in 1970. I asked why we weren’t looking at 4 barrels. He said they were hot rods that needed Ethyl (premium) and we didn’t need one. We ended up with a Dodge Polara Custom (the luxury model). It had a 383 2 barrel. It ran on regular and moved that car quickly and quietly! Oh and it got 18 mpg.

My first car was a '70 Olds Delta 88 Custom 4 door hardtop... it had the 310hp 455 - 2V and I found it to be an excellent driving car! It may have been lower hp but it was plenty torquey and I never felt it lacked in any situation. I think she ran near 500 lb-ft so... no worries! A good friend of mine had another '70 Delta... a ragtop with a 350 - 4V and mine was considerably quicker. I think the 350 - 4V also had 310 hp but less torque. Both very nice driving machines... the glory days of the General!!!

My girlfriend had a 69 Olds 88 with a 455-2v, and it was a blast to drive! Monster low-end torque got that heavy beast going pretty quick, and even on the freeway, there was power to spare. All you had to do was put lots of gas in it!

I've never driven anything with a big block. The biggest engines I've ever owned or driven were GM small block 350s, and my 77 Dodge Adventurer pick-up had a 360. I've always wanted a big block car. A 1970 premium fuel big block GM would be my top choice. But really, any big block over 400 cubic inches of any year or make would be great

@StringerNews1

2 ай бұрын

You'd better hurry, or you'll miss out. I grew up on big blocks, and just recently bought an '86 460 CID Ford truck, just to have a taste of big block life one more time. Now the '86 motor doesn't scream like the 460 in my parents' '69 Lincoln, but it's still a big block, and fun to drive.

@joeskeptical4762

2 ай бұрын

*You haven't lived until you have taken a mid 60s Cadillac through a highway on-ramp at full throttle up to 90+ mph. Smooth, steady and pulled like a rocket.*

@donreinke5863

2 ай бұрын

@@joeskeptical4762 My ex-girlfriend and I installed a 1975 Cadillac 500 in a 1981 Fleetwood Brougham that blew up (of course) its stock 368 ci 8-6-4. In the lighter post 1976 body it was an amazing performer, and virtually a bolt-in swap. Took it out one night on I-70 east of Denver, and it seemed like it would never stop accelerating. We left the 200-4-R overdrive transmission in it, had no idea how long it lasted.

@jnywd8450

2 ай бұрын

As an old fart, I've rolled around in a few big block cars. Some stock, some built. They put a lot of extra wear and tear on the rear tires.

Both fascinating and interesting ! I love Oldsmobile engines period. Have a low mile classic ‘76 Cutlass Supreme with a 350 4bbl. Smooth and dependable!

If you're not going all out, to high RPMs at Wide Open Throttle, a two barrel carb will still provide a nice snappiness, when taking off with a little quickness.

I heard if you keep your foot out of it, a 4 bbl carb will use less gas than a 2 bbl

@jamesweidinger1117

2 ай бұрын

If you keep your foot out of it, a four barrel carburetor IS a two barrel carburetor.

@StringerNews1

2 ай бұрын

It's true, especially with a spreadbore like the Rochester Quadrajet. If you're drag-racing, using high numerical ratio rear ends, and launching near the redline, then CFM matters. Everywhere else, other things like fuel atomization and ram effect play a much greater role. A 4-barrel carb is more efficient all over, compared to a 2-barrel.

@kc9scott

2 ай бұрын

And the same engine with a 4-bbl will have slightly higher MPG rating than a 2-bbl.

@StringerNews1

2 ай бұрын

@@kc9scott in fact, a somewhat popular modification after the Arab oil embargoes was to disconnect the vacuum line on vacuum secondary carbs, to keep the secondary barrels (of a 4 barrel carb) from opening. The impact on drivability was minimal, as maximum air flow is only needed at maximum load. Everywhere else on the power curve, the higher velocity leads to _better_ performance. Better fuel atomization is more efficient.

@dmandman9

2 ай бұрын

It’s true because the primary barrels of the 4 barrel carbs are smaller than those of the two barrels.

People want lots of horsepower without understanding that having lots of torque is what makes a car with a big engine so effortless to drive.

Back in the early-mid '70s, my folks had a pair of '68 Olds Delta Customs - 2-dr 'holiday coupe' fastbacks - both with 455s.. Mom's was the 365hp high compression 4-barrel, dad's was the low compression 2-barrel. Dad's 2-barrel car actually had more options on it - vacuum power locks, vacuum power trunk release, cruise control, rear defogger fan, and the 'halo' vinyl top. IIRC, the side trim was different between the two as well. Mom's had the more deluxe set-the-temperature AC system. These cars were geared for highway cruising at 75+mph, so when the Feds lowered the speed limit to 55, they actually got decent gas mileage. By decent I mean well over 18mpg - yes, with 455s!

I had a 1970 Ford Country Squire wagon with a 429 2-bbl. Instant power when you stomped on the gas, no hesitation from secondaries opening.

Ford produced a lot of 2 barrel "McNamara" big blocks with two barrel carburetors. On the surface it sounds stupid, but when you get into the engineering, it makes tons of sense because these make tons of torque which people like while not using tons of fuel or producing tons of emissions. -Really, the American auto companies should have advertised this back in the 1970's. "Big but slow turning equals efficiency!", just like the high bypass ratio turbofans on modern airliners. My spouse is from Belgium, and when she first came to Flori-Duh, we had my mom's '89 Bonneville SE to take down to Key West. This car had a 3800 engine and was fast off the line, yet it ate 9 liters/100 km despite being the size of a Mercedes Benz S class on the inside. She fell asleep on the way down because the 3800 only needed 1800 rpm to do 70 mph and the relaxed sound and the soft seats lulled her.... "I'm not sure why this isn't sold in Europe!" I remind her to this day about this statement. "You picked an American, we are pragmatic first".

I know it’s about big blocks, but I have 400 Chevrolet small block with a 2 barrel. I agree they feel peppier around town and for most driving conditions you’ll not get into the imaginary secondaries…

One of the most anemic Chevrolet was 69 Caprice with a 396 -2 barrel. A terrible combination! There’s a road test video that confirms how bad it was.

@johnz8210

2 ай бұрын

Yes, Bud Lindemann's road test.

@roger628

2 ай бұрын

@@johnz8210 I still maintain something was wrong with that car. It couldn't have been THAT bad!

@Lucille69caddy

2 ай бұрын

@@roger628 I concur. When Bud Lindemann said “it couldn’t punch thru a wet tissue”, I about lost it.😆

Those big engines got 16-18 mpg if driven right if they had tall gearing.

Thank you for the informative article. I especially enjoyed seeing the pictures of the big blocks sitting in spanking clean engine compartments. It brought back a lot of memories from decades ago.

I was 17 when my Dad bought a 1969 Olds Delta 88 with the 455 and 320HP and GM400 tranny. I got to drive it a few times and I remember how smooth yet powerful it was. If I remember right, I think he paid around $4200 for it.

Funny, I just had a conversation with a friend about the Buick 2 barrel 455 of 1974 a few days ago! I just sent the link to my friend! I think it was also available in the Century/Regal that year (1974 was also the last year Buick offered big blocks in it's intermediates).

Back in the 80s one of my sisters had a 70 Bonneville with a 455 2bbl. It had a very diesel-like power delivery. Lots of low end but ran out of breath early. Not that you’d spin up your Bonnie very often 😂 I don’t know about how or why but it was definitely a 1970 not a 71. 🤷 Maybe someone retrofitted it during the gas crisis.

I almost purchased a Catalina wagon with a 3 speed on the tree and a high compression 400....but it had a 2 barrel. Always thought it was an odd choice but I believe those wagons only optioned a 4bbl with 428 in a Bonneville wagon. I should've bought that wagon but it'd be sitting with a RAIV camshaft, aluminum Kaufman heads and 4.56 gears. You know, because what else do you do with a station wagon.

@michaelbenardo5695

2 ай бұрын

Wow, a 400 with a manual trans! I sure would have grabbed it!

I suspect the spec sheet shown for that Pontiac offered a clue: If you chose the 2.73 rear, you'd get a quiet highway cruiser; if you chose the 3.23 you were towing with it. And the 4bbl only came with the 3.08 to split the difference. And yeah, with its smaller primaries, the Q-Jet got better MPG if you never opened up the secondaries.

Adam, Our '73 Caprice Estate had a 400 V8 with a 2 barrel. Therefore, an 'Economy Olds 455' sounds like a fine idea to me as long as I can get it with a dual exhaust.😉 I have also driven cars with 1 barrel carburetors that made me dream of an upgrade to a two barrel. 😁

@georgewetzel4380

2 ай бұрын

Why dual exhaust?

@rightlanehog3151

2 ай бұрын

@@georgewetzel4380 Dual exhaust provides a measure of extra horsepower and better fuel economy by relieving back pressure without the hassle and expense associated with 4 barrel, high compression engines. In the old days there was often a difference in compression ratio across the range of V8 engines . The Economy 455 would have run on regular fuel. Then as now, you save money with cheaper gas.

As a young g m mechanic in the eighties I saw variance of five ton trucks with two barrels big block.

Excellent post. I'm a Ford and Mopar guy who always liked Pontiac and Oldsmobile too. Thanks for the research and presentation. By the way, I achieved 17.6 mpg TWICE with my 1970 Mercury Marquis, 429 2-barrel. Summer weather, highway driving.

@marckyle5895

2 ай бұрын

My '73 Galaxie with the 2bbl 400 got 15-16 back when the speed limit was 65 and I obeyed it. But it had enough torque to pull a fully loaded u-haul trailer at 90. 2 barrels are nice if you get them set up with the jetting right and find a replacement with larger venturis! Fords went all the way from a 1.08 diameter 2bbl venturi to at least a 1.33, which meant about 150 (or more) more CFM.

@warrenwinslow4266

2 ай бұрын

I got 18.6 out of a 460 Ltd landau 4bbl

@67marlins

2 ай бұрын

@warrenwinslow4266 Wow. That's excellent. Pre- 1975 I assume ? ( I just read that was the beginning of catalytic converters.).

@LongIslandMopars

2 ай бұрын

My 66 Coronet with a 273 gets about 12 mpg no matter what I do.

Great video. Thanks.

I had a Oldsmobile 425 big block that was balanced and blueprinted and it had a lot of torque. I love big blocks.

The 1969 full size Chevys had a 396 2 barrel as a optional engine.

@markg7030

2 ай бұрын

Yes 265 horsepower. It was not a screamer but you got those 396 badges on the fender.

@marckyle5895

2 ай бұрын

@@markg7030 bragging with nothing to back it up

@gerryvandepol7630

2 ай бұрын

Had a 396 2 bbl in a 69 C10 3 on the tree work truck plain jane zero options..

@ONTHEEDGEFRED

2 ай бұрын

I was going to mention this where ole Bud.Lindman did a review on one of those Impalas, , with the 396 2 barrel,l said it couldn't get out of its own way

Starting for the 1971 model year, GM capped compression ratios to 8.5:1 in all engines for compatibility with the coming low and unleaded gas.

I remember the Chrysler 383 with a 2bbl was a torque monster, at least from a seat-of-the-pants standpoint. On the Quadrajet primaries, you may recall that GM introduced a 2bbl carb in the late 70s that was just the front half of a Quadrajet. I had a 79 Caprice with the 305 and one of these carbs and it was very peppy. It felt choked off if you tried to rev it out, but was very pleasant and pulled good at lower rpms and part throttle.

@paulkirkland1535

2 ай бұрын

I had one of those carbs on a 301 Pontiac V8 in a Buick Le Sabre. Like you said good low end torque. Mine ran quite well in the 70-75 MPH range.

@Bloodcurling

2 ай бұрын

Wasn't the front half. 4bbl have smaller primary

@Gary7even

2 ай бұрын

@@Bloodcurling You are wrong. It was a 2bbl carb made from just the primaries of a Quadrajet, i.e, the front half. It was actually called the Rochester Dualjet carb. Google it.

@jamesweidinger1117

2 ай бұрын

The early Dualjet carbs were full size Quadrajets with the back half unfinished.

@Gary7even

2 ай бұрын

@@jamesweidinger1117 Mine was literally just the front half. No secondaries or even a place for them. Like this one: kzread.info/dash/bejne/oqNoqNNrg9HalqQ.html

Thank You Sir!, I,m 54 and respect the content!

Had a '68 Olds Vista Cruiser with 4 bbl 9:1 compression 400 in it. It was a tire fryer and it got 15 on the highway running mostly on 7 cylinders (don't ask). The car was pile but a blast too.

My grade 11 English teacher had a '70 Delta 88 with a 455 2V. Seemed to work OK. As you say, some of those GM 2Vs flowed pretty well. They were good carbs. I owned quite a few although never on anything that big.

Ford had a 429 2bbl, and AMC had a 2 bbl 401. I had a 1974 IH pickup with the AMC 401 2 bbl (and Dodge 2wd front suspension). I think the 429 2v was a 70 or 71 Mercury.

I had a '72 Pontiac Bonneville with the 455/2bbl. Enormous boat of a car. Fair amount of grunt up to about 30 mph, and then it just ran out of wind. Not slow, per se, but not as much power as you'd expect. Hit passing gear on the highway and you could hear the engine desperately dragging at that tiny carb.

I love your channel ..very informative..well done

A high school friend of mine drove a 1966 Pontiac Catalina with a 389 2 barrel. That engine pulled hard! It was a big car as well. I was impressed!

I've always thought it strange that Ford always called barrels venturi's, as in 2v or 4v. The three deuce setup was the best of both worlds. 2 barrel for cruising, and always having that extra power when needed. Thanks!

best part about the big block v-8's was their sound -- you could feel it deep down in your gut. i miss that sound. eventually all we'll have is silent ev's. never heard sweeter music than a big block with a lopey cam

@michaelbenardo5695

2 ай бұрын

Just grab a big block V8 car now, and don't get rid of it.

I had '69 Olds Ninety Eight with a BB 2bbl, the car ran great and I never gave it much thought. I sort of assumed a former owner had swappe out the carb and intake for mpg back then, but the car only had 19,300 miles on it when I rescued it from probable demolishion derby duty back in 1983. I kept it for a couple years and sold it at auction after buying a '70 Lincoln Mk III which I wish I still had. The Olds 9:1 comp. 2bbl 455 still made more power than the 70 Impala I had prior with only a 250hp 350 sb, also with a 2bbl carb.

My brother had a 69 firebird with a 350 2bbl. He put a 4bbl and dual exhaust off of a 455sd 73 firebird on it. It went from barely getting out of its own way to smoking tge tires around tge block, and that was a 2.73 rearend and a powerglide

Great presentation…as usual.

I always assumed my 68 Delta Auto-trans 2-bbl was low compression and that the "pinging" was just the Oldsmobile sound. Thanks.

The 455 2 Barrel made it's way into the now highly collectable 1970 and 1971 Cutlass SX as well. Had a friend who owned a Metallic Blue one with a Hurst Dual gate shifter and white buckets. It was a really nice car....they only made 1820 of them. The 455 - 2 worked out pretty well in that car - even with the open rear axle it really felt strong and did well on the street in the 80s. I was jealous as I had a 72 Cutlass Supreme 350 4 Bbl.

@bbsbcv

2 ай бұрын

My first car was a 1970 SX with the high-compression 2-bbl 455, dual exhausts through a cutout rear bumper and the 2.56 posi rear. This was back in 1983, when it was a basically forgotten model and nobody knew what they were. All I knew was that there was a "Rocket 455" sticker on the top of the air-cleaner. The first thing I did was buy a used factory 4-bbl intake and carburetor and replace the the stock intake. Great torque from that engine.

@gt-37guy6

2 ай бұрын

@@bbsbcv Holy cats the top end on that car must have been 140 ish.... There is a Red 77 Regal out on Utube with a 455 Buick with 2.56 and that car holds a speed record in that class. 168 or 172 ...somewhere in there. It also pulls a 12 second Quarter with that rear end!

@bbsbcv

2 ай бұрын

​@@gt-37guy6, yeah, I know I had it where the needle had wrapped past that 120 mph tick on the speedometer and was basically pointing straight down. But the real feature was how comfortably it could just cruise at 100 mph with no drama whatsoever.

@gt-37guy6

2 ай бұрын

@@bbsbcv We must be living some parallel here, did the same with a buddy in a 70 GS455....same story highway gears, wrapped out top end until it was straight down. A GTO I was in with another friend just snapped the speedo cable at the same time the Kawasaki cycle we were racing also broke his! Unreal stuff - great to hear your Olds exploits....

@robb1165

2 ай бұрын

@@gt-37guy6 I had a 70 442 with 3.73 gears in the 1980's. My bracket racer. It ran 142 mph in the 1/4 mile. Topped out somewhere around 170 mph at 8200 rpm. Rpm limited by me, built to probably survive 8600+ rpm.

Adam, your spot on with the 2barrel. Great performance for everyday driving. Now if your going to pull a camper, boat, ,etc. you would need a 4.I loved my 2barrel in every GM I owned!

That green ‘74 Buick is beautiful..Loved this engine discussion…Too bad we can’t speak to engineers of the era about that ‘74 Buick 455-2…to find out what they were thinking.

@Lucille69caddy

2 ай бұрын

Why not?

@markmaiello9180

2 ай бұрын

@@Lucille69caddy Does Adam know any?

*Doesn't seem strange at all, most of these 455 cubic inch 2 barrel cars were cruisers driven that way, Such car buyers liked strong torque right off idle, infrequently going above 4,000 rpm. Even Cadillac owners were unlikely to push the car hard at higher speed, but when that happened the Caddies, especially with the mid-60s 429 and 472 engines, could move well and sustain 90-100 mph easily. Even if this was not done often, it was expected for the high price. The performance difference between a 2 barrel and a 4 barrel of the same car and engines was only noticable if both versions were driven hard back-to-back.*

2bbl big blocks with low compression are a great idea for the buyer that might tow a boat or need more power but wants regular gas. Also makes for a very reliable engine thats under stressed and has a simpler carb.

I like how detailed the old vehicle configuration sheets were back then. They didn't seem to try to hide anything and there were lots of options to choose from. Now and days, if you were to look for a new vehicle, there's just not much config to have other than a select few colors and drive option (4wd, awd, 2wd) and maybe different wheels.

Absolutely loved the Pontiac and Olds 455-2bbl. Simple but powerful.

The four barrel engines also got a slightly larger camshaft, and sometimes standard dual exhaust, vs the 2 barrel engines.

My dad had a 1969 Oldsmobile Delta 88 with a 455 and a two barrel. He was transferred to Spain and got that particular engine configuration in order to burn regular gas instead of premium. Was very fast and pretty reliable. We went all over the country with it and towed a small camper. Definitely a sleeper. He sold it to the Spanish government for use as a limo before he came back to the states. I remember that car fondly.

Not the 455, but in 1967 and 1968 there was a "turnpike cruiser" option on the 400ci big blocks in the 442. (So much for the 4bbl part of the definition of 442.)

@tholmes2169

2 ай бұрын

Yeah my Dad had a 68 442 back in the early 70s, his had a 4 barrel but we had the old Dealer brochure with the turnpike cruiser option. I believe the GTO had the same option those years.

As a teen in the late ‘70’s, I got to drive my uncle’s ‘71 Delta 88 455 2bbl..car was dark brown, black vinyl top and interior..ac car..had gobs of power around town in the lower Hudson Valley/NY..I always wished he would have sold me that olds

My Grandfather bought a 1972 Bonneville hearse with the 2 barrel as well he also purchased a 1975 Bonneville with the 4 barrel after he died my mother inherited those vehicles and according to her the older hearse would out perform the younger one.

@michaelbenardo5695

2 ай бұрын

No EGR, less exhaust back pressure, which means less pumping losses.

Yep Adam, interesting stuff and there's always a reason why they do these things....Sales higher with 2BBL's & maybe more fuel efficient too, as well as, more power possibly not necessary with the speed limit 55 MPH on the roads in the U.S..Cheers fm Damo😀👍

The green 71 delta was exactly what I had even white walls. Got it in early 90's with 13,000 miles. Probably be favorite vehicle I've owned when I permanently hang up my keys.

Mom had a 70 Delta88 4dr 455 2bbl. Locomotive torque. Very peppy around town. Freshly tuned would net 14mpg hwy. Entire family loved driving it

Nice video. I was wondering what you put in the gasoline to help preserve it while you store your cars. Thanks.

For some reason I always thought the compression on engines dropped for the '72 model year rather than '71. Interesting, thanks!

My 70 Olds Cutlass SX had the 455 with 2bbl.

I remember as a kid being surprised by the little 2barrel carb on our old ford grain truck😂

When I'm working on my Honda J Series engines and I'm rooting around in my sockets tray I'll sometimes see the old spark plug socket I used on those big ol' plugs in our '72 455ci Olds Toronado. I can drop an NGK spark plug down through the inside of it and it won't even touch the sides.

What Adam said about the 2 barrels feeling peppier at low speeds and 4 barrels at high speeds makes so much sense. Notice the ratio of horsepower to torque for 2 vs 4 barrel in the brochure. It means tq peaks at lower rpm for 2 barrel, and the extra hp of the 4 barrel can be felt at higher speeds

Gotta love the 1970’s big v8 motors we have 460 cubic inches making 137 horsepower thanks big brother

That black Bonneville at 8:49 looks like it could be yours Adam, with those turbine-ish Colonnade Lemans wheel covers. And the nice looking red Electra convertible @10:33 is about identical to one a family in my neighborhood owned for quite a few years from new. Theirs had a white top, and I don't remember the interior color.

In late 80s high school had a 69 Delta 88 w/ 455 2bbl paid 800$. Changed rear tires monthly in shop class. Turbo 400 trans took a beating. God help you if you try to stop fast more than once in a row. 4 wheel drums. The epitome of the "blue bomber".... 4 door , big block fun on a rolling couch.

The Olds high compression 2 barrel 455 is reminiscent of Olds' work on the Cutlass Turnpike cruiser, which effectively was built on a 442 chassis, but set up with a High-compression 2 barrel 400 and a tall rear axle, where the GTO for example could be also be had with a 2-barrel, but only on a low-compression 400 clearly advertised as an economy option.

The early Olds weren't all that heavy on the HP but a beast in the torque dept.

The restrictive 2-barrel intake allowed the engine to create lots of manifold vacuum. This was necessary to run the power steering and breaks. You could steer those giant cars with your pinky.

@jamesbulldogmiller

2 ай бұрын

power steering is hydraulic with a belt driven pump.

my grandmother had a 1970 LTD with the 429-2V that car was a torque monster. my first car was a Old Delta 88 with the 455 4 BBL.

I had a 72 Buick Centurion with a 455 2-barrel, and also a 74 Ford LTD with a 400 2-barrel --- no lack of power in either.

My 69 Oldsmobile Delta 88 custom had a 455 V8 with a 2bbl carburetor . It was a very great engine, I miss that car

Now I understand we are talking bout GM engines, but there have been a few Big Blocks from other manufacturers. Mercedes Benz built a 6.9 liter V8 in the '60's, and though it wasn't very powerful, it could sit at 125 mph on the German Autobahn for hours at a time, something NO American engine could do in stock form. It was literally an aircraft engine. Porsche built the 5.4 liter/329 cubic inch M28 V8 for the 928 car, and it has almost the exact same bore spacing as a Chevy big block, and for that matter a 440 Dodge. In fact, Arias in California has mounted 4 valve DOHC M28 heads on a 502 Chevy big block and the resulting engine will pass California emissions while making 550 hp all day long....

Adam, sorry I'm late getting in on this. I believe a large part of the reasoning behind big-blocks and 2 BBLs, was sales. I remember a lot of talk going on back in the day, from people who had bought brand-new '69 &'70 Impala's and saying that it used more gas than their old Impala. Meaning their '64, '65, '66, '67, Impala's. That seems to mark the introduction and wide-spread use of the then new 350 engine. GM knew that the coming emission controls would lower gas mileage. And salesmen were ready for concerned customers in telling them things like "...but it has a two-barrel carburetor" and "...it should be pretty good on gas because they (GM) put a two-barrel carburetor on it." That worked for a while, and after some time into these thirstier cars, the salesmen's pitch then became "I know that GM is working on getting the mileage up. You know we got caught short when the government mandated these emission controls. Pick one with a two-barrel carburetor."

What was Rbt McNamara's logic behind 2 barrels, esp in the Lincoln? Great video, thanks Adam!

It was all about getting good fueling. In town and on the rural routes they ran great.

The 2 barrels would also frequently come with a milder cam, sacrificing some high end power for additional low-end grunt.

My friend in high school drove his dads 73 lesabre, 455 2 barrel. It was a one tire fryer. Lots of fun when turning out of mickey d’s and lighting up passenger rear tire.😁

I had read about 455 2bbls, but have never seen 1. I did have a friend that had a 69 caprice that had a 396 2bbl, which i found rather strange. But then too, all chevy sb 400s were 2bbls. Alot of ford truck hd engines were also 2bbls, like 352s and 390s. Maybe buick was trying to respond to the gas crunch in 74? I can't imagine it would get all that better mileage even with a duece. I had a 383 2bbl in a 69 fury lll sedan that was indeed peppy around town even with 2.94 gears. But it was still horrible on gas.

Had a BB 350 2bl in my 73 Buick centruian. Great car.

You forgot about the 396 chevy 2 barrel 265 hp. at 4800 and 9.00 compression

@madmike2624

2 ай бұрын

spot on!!

In the end you described the whole reason for it, more torque.. Also, i think the first GM big block to have a 2 barrel was a 396 Chevy in 1966 or 67 in the Impala..

@mattbauckman9907

2 ай бұрын

1969, one year only. 265 hp. 9:1 compression, same cam as 325 hp version.

If you look closely, the Olds 455 2 barrel had only 10 fewer ft-lbs of torque compared to the 4 barrel version. Around town, the power felt the same. I mean, how many people rev'd an Olds to 5000 rpm?

Those charts are interesting in that they show NET vs GROSS HP. I’ve always wondered what the actual figures were!

Adam i had a 74 Buick Electra LTD 455 for the life of can't remember what carb it ! But it was a awesome driving car intown or highway 👍Sure do miss that car ! It had a ton of power 👍

I also felt the same way about inline 6s back then having one-barrel carbs.

always interesting

Hello Adam I've owned a few early 70s B bodies My 71 Bonneville had the 2V 455 like you said nice in to and really not bad on the highway too But uphill and passing seemed like a real chore sometimes Lack of horsepower was obvious but just for daily driving I could live with the gas milage I also had a 73 Catalina coupe 400-2V Performance was very similar

@michaelbenardo5695

2 ай бұрын

It was not because of a lack of horsepower, it was because of super-tall graring.

A few he left out were the 1969 Chevy 396 2bbl 265hp 400 tq, 366/427 Chevy tall deck truck engines pre-69, Oldsmobile 400 2bbl available in Cutlass 442 as a part of the Turnpike Cruiser option, Chrysler 383/400 B engines, 1959-60 383 RB engines and possibly a 413