commander_47

Name calling? Where do you see that?

You dont like references? You dont believe me and claim i am mechanically inept. I thought you would enjoy another perspective.

There are reams of articles about the junk.

Dont forget lane automotive.

Holley has been around since 1917, and is still going strong. Every major american car company has used them for years and years.

The more successful carbs out there today are Holley derivitives.

The use on daily drivers and race cars is long and storied. And the legacy continues today.

Simply check with the royal grand wizard extraordinaire Lars. He has written and posted many horror stories about q warpage, leaking, stripped threads and more.

I feel bad for the guys who count on lars. What happens if he retires?

I really don't care what carb a guy runs.

It does gall me when someone seeking advice is fed a bunch of pablum about a marginal antique that has been relegated to the trash heap of time.

Recommending a guy new to the sport a mechanical nightmare that limits your choices, is a pita to work on and find parts for is not doing him any favors.

And went out of production 15 years ago.

The13Bats

you hate qjets, It's not a... subtle point that you're making.

In the spirit of seeking advice, tell me something, yes, your opinion,
Why do so many people here have such good luck with qjets, many went from holleys or edelbrocks, some just had carb issues and had their qjet rebuilt and love it, so if qjets suck so badly why do some people dig them so much and have great running cars with them...

commander_47

Nothing inspires a more spirited conversation among car people as Carbs, cams and exhaust.

Carbs are the Heart of an engine, cam is the brain, and the exhaust is the ....well you know.

I am an old retired hot rodder from back in the day. I have built and rebuilt these cars and bikes because I love them. I've raced them and shown them for decades. Though mostly show now.

The bottom fell out of the old school hot rodder in 1971 with the advent of the smog regulations and so called gas crises. The same time the Q junk became standard in most GM cars. Same carb in everthing from 6 cylinder econo boxes, to big block econo boxes.

This has finally come full circle. it is amazing how much these guys are doing today. I'm so happy the new C-7 vette is taking the world by storm. What an inspiration!!!!

My wife wants me to sell my C-3's and get a new one. I don't believe I could even change a tire on one of the new ones! Let alone work on it.

My main issue with the Q is that it was never designed to be a good carburetor. It was designed as cheap replacement for GM. This is factual and easily researched. Look it up.

GM pushed for, and got, the smog guidelines so they could detune and sell more cars at a higher profit margin. They loved it. The insurance companies loved it, and us hot rodders HATED it.

When GM realized a significant number of people didn't like the q, they tried to push it into the performance category with a few highly modified Q's.

Of course, your average hot rodder did not have the tools, or parts, to perform these major modifications. The same is true today. Even more so since parts are getting scarcer, and so are gurus like Lars.

Even Lars won't rebuild a E4E q unless you bring the car to him. It has to be tuned that closely to the CCC!!!!!!!!

If you like to plod around and drive your corvette like the family sedan, the q is adequate as long as you don't have any issues, which you will. Detailed in some of the above posts.

According to AMCAR the ten fastest muscle era cars:

#1 1966 427 Cobra 427 cubic V8 425 HP (4 barrel Hollley. Some early ones had 3 Webers which I put in same category as q junk. Some Cobras had 2 Holleys)

#2 1966 Corvette 427 cubic L72 425 HP (Holley 780 4 barrel)

#3 1969 Road Runner 440 cubic Six BBL 390 HP (3 Holley 2 barrels)

#4 1970 Hemi Cuda 426 cubic Hemi 425 HP (3 Holley 2 barrles)

#5 1970 Chevelle SS454 454 cubic LS6 450 HP (4 barrel Holley)

#6 1969 Camaro 427 cubic ZL1 430 HP (850 Cfm Holley 4 barrel 4296, or Holley 4 barrel 780 CFM 4346)

#7 1968 Chevrolet Corvette 427 cubic V8 435 HP (3 Holley 2 barrels)

#8 1970 Plymouth Road Runner 426 cubic Hemi 425 HP (3 2 barrel Holleys)

#9 1970 Buick GS Stage I 455 cubic 360 HP (Finally, a q junk. A highly factory modified 850 cfm carb no mere mortal could duplicate)

#10 1968 Chevrolet Corvette 427 cubic 425 HP (4 barrel Holley)


So of the top ten performance cars from the muscle era, you have 9 Holleys. One of which broke the land speed record at the time. And one q junk, not in a Chevy, but a Buick)

The13Bats

Nice long winded semi rant of smoke and mirrors riddled with inaccuracies intended to just avoid and derail my question to you, "Why do so many members on this forum have fine operating Q-jets on their cars performing great?

Shark Racer

I'd love to see your cited resource for this. Smog restrictions do not benefit manufacturers at all, nor does de-tuning(except possibly in the case of transmission and differential warranty, but THM400, Muncies and the 10-bolt diffs were really up to street use in just about ANY engine combination the factory offered).

Your definition of "highly modified" is a carb with a slightly different casting. The primaries are not as responsive as the primaries of a 750.

Some of what you say here is true - it's not trivial or easy to convert a 750 casting to an 850 casting. The tools I use to rebuild a QuadraJet include: phillips and slotted screw drivers, dial calipers (a machinist ruler will work) and that's pretty much it.

Going to a bit more major stuff - increasing CFM requires a pair of needle nose pliers.

Tuning the air valve windup requires a small SAE hex key and a small screwdriver (think jeweler screwdriver).

This is where Lars draws the line - and the funny thing is, 99% of people don't need anything more than this. He may go on to rebuild throttle bodies but that's not typical, only if they exhibit an unstable idle problem. Funnier yet, once the carb is set up correctly they tend to run really well.

Now, overhauling the throttle body when worn badly (and yes, a carburetor with 100k + miles on it is going to need this) will require a bit more specialized tools. A drill press or a self-indexing drill. Not cheap. This is also true of a Holley - their aluminum throttle bodies wear out too. It's just less common to find Holleys (particularly 4150/4160s) on high mileage cars. 4180s are a different story and I'd take a Q-Jet ten times over before I took one of those.


You're skewing data here like a politician. It's true that Lars won't tune an E4M - Lars' process includes tuning and verifying idle and responsiveness. Without the ECM in place to control it, the mixture control solenoid will be stuck in full rich mode. This impacts cruise and idle. He could tune both to stoich but you'd end up having a carburetor that could not compensate for lean conditions at all. Considering he lives at high altitude, this is a fairly dangerous proposition.

E4Ms are a fair bit harder to work on - you do need more tools (a dwell meter and some tools for adjusting the lean and rich stops of the MCS). They are definitely a big step up from an M4M. You won't catch me disagreeing with you. I've done 1, it was a big pain, I'd only do it again with the car in front of me. The second one would not be anywhere near as bad, though.

I enjoy plodding around in mine, particularly around 6100 RPM (the spark rev limiter is set for 6200). If I weren't saddled with smog laws where I live, I'd have gone for 6500. Oh well.

Yeah, like I said, pretty much all the BOP high performance stuff ran a Q-Jet. Olds 442, Poncho's Ram Air cars, Regal GSX, etc. Chevy and Ford did not. Do an image search for "pontiac ram air carburetor" and you'll get a lot of Q-Jet pics, if you're into that (don't worry, I know you're not ).

The problem, and I've told you this many times in the past, is that these carbs have been on cars for 30+ years and have had a history of strange things done to them. A Holley would run just as badly if someone put all 8 float bowl screws on with an impact gun, dropped the throttle body on the ground and cracked it then put it back into service, melted lead into the idle air bleeds and cranked the idle screws up so it would run off the main circuits instead, etc.

You definitely get a "reset" with a Holley, a fairly strong guarantee that it was assembled correctly and all the appropriate parts are there. A baseline. You may not have that with the Q-Jet on your car or the one you buy on eBay that someone pulled out of a dumpster.

But, with a $50 rebuild kit and maybe $20-30 in hard parts, you can take that Q-Jet and have it run as well as a $500 Holley. Hard to beat the $400 savings.

Even if you have Lars do it, you'll be very much cash ahead.

To me, though, it's not about the savings - it's about how well the car runs.

It probably helps that, like Lars, I'm a trained engineer and appreciate the systems on these things. They really don't seem that complex and I understand how they all work together (for the most part).

commander_47

Oh, I get it, you really don't want to discuss the Q at all, just put me down like the other effete q jet junkies. Silly me, and I fell for it.


All you rocket scientists can get together and lose at the track and work on your q junks. You can continue to sucker the young and uninformed about this abomination. They will end up with Holleys anyway.

I'm just trying to save them the useless expense of restoring a warped turkey.

The q warps and leaks. It is undependable and difficult to tune. Parts are hard to find and not even professionals rebuild them right except for the omnipotent Lars.

It has never performed well at the track and NO ONE of any importance ever used them.

They are smog carbs, if you monkey with them you remove the smog capability. They will NEVER perform as good as a Holley or any other Carb.

Simply put, they suck.

So you guys who love these things, rock on, but newbies......be forwarned and armed. They were junk then, Junk now, and will be junk in the future. Save yourself the ride....Get a Holley or Holley clone now and join the winning circles.

commander_47

See the above. That was meant for you.

Shark Racer

And I don't know where I put you down at all in that post, except calling out that you were putting out skewed data.

I'm probably about half your age, dude. I've got about 20 years before I can dream about retiring.

Aside from John Lingenfelter, which you mentioned before.

My monkeyed-with carb passed smog and did 450hp/484 tq on the engine dyno.

widowmaker221

Now take that same motor and replace with a Holley and put back on the dyno , I bet an increase in performance is just waiting to be unleashed!

commander_47

I guess you all think make this stuff up. You easily research it yourself. Back in the day it was in all the news reports.

Here is a quote from a story from the Bridgeport Post in Connecticut. May 31, 1970 title " Autos polluting the air, an exhausting problem"

Bills have been introduced in Congress and some .state legislatures to outlaw the internal combustion engine, which now propels your car. Edward N. Cole, president of General Motors Corp., insists the internal combustion engine "can he made essentially pollution free" by 1980, and estimates hydrocarbon emissions have been reduced 80 per cent and carbon monoxide 65 per cent since first control steps were taken In 1961.

GM jumped on that by creating the Q jet. They were happy because Holley was too expensive, and they wanted a cheaper one size fits all. So they built them cheap. That's why they warp.

Also, the insurance companies hated the fast cars. They wanted plodders. GM teamed up with the insurance companies to enact the smog and 55 mph speed limit. Research it, it is easy, there's tons of stuff to read about it.

I lived through it back then. I had a 66 Galaxie XL 7 liter

Finally, the q junk in the Buick was not just a standard 800. It was highly modified. Do your research.

None of the Q jet cars come close to the nine in the list. Even the Buick is the lowest HP.

That's also why Holley now provides the bodies for the new GM efi cars.

The ram air

Finally, I'm not sure what you are talking about with the Pontiac, by 1975 that venerable trans am was reduced to a 185 hp plodder. More references since no one on here believes me:

None of the Ram air cars produced more than 366 hp, and the last of big block "high" horsepower models SD454 was only 290.

http://www.2gta.com/1975ta.html

The lone mainstay of Trans Am production, the instrument panels remained the same, engine turned applique and all. The instruments themselve's however, took a drastic change. Gone was the oh-my-God 160-mph speedometer, replaced by a more realistic (but sad) 100 mph unit. The speedometer change was in response to the ever tightening government's noose. Theory was, if we only put a speedometer that reads up to X mph, then Joe Public will only be tempted to go X-mph. Guys, this is a Trans Am; give the people what they pay for.

I It seems a wheezy 185 hp 400 was the base motor, (it's power nearly halved from the Ram Air IV hey-day) barely had enough horsepower to make a speedometer which progressed past the 100 mile per hour mark an issue. Not only was the power produced utilarian, but so was it's power band, peaking at a mere 3600 rpm. With days of 3.73 gears long since gone, this meant it's power peak would be achieved while cruising at about 60 mph. The torque peak of 310 lb/ft at 1600 rpm was more suited for the axle ratios of the current period, giving a nice thrusty feel at the national speed limit of 55 mile per hour. If a Turbo-Hydramatic 350 was mated to the 400, the engine was coded YS . Applications the called for the 4-speed manual go the WT coded engine.

commander_47

I wasn't addressing you in this........sorry.

see above

Shark Racer

I probably wouldn't be able to handle it - I'm used to plodding along in my Q-Jet. (Not really meaning to dig at Gordon - I couldn't help but say it though )
I may have to. I'm not trying to accuse you of making it up, but it's not a statement that I'd be willing to take at face value.

Sounds like the president of GM assuring people that GM will be able to live up to the quality standard set out by the gov't, doesn't really say that Ed Cole sponsored them.
They warp because of the front bolt design. When they aren't man-handled, not really a big deal. Put in a hot engine and bubba with his big ratchet and you'll warp a Q-Jet in a couple heat cycles. I'm not going to say it's a terrible design, but they definitely didn't plan around bubba. And yes, it creates a huge problem.

I'll have to.

I lived through the boxy junk of the 80's. So all the new hot cars were junk compared to the stuff that came before I was born. When things started rounding out in the 90's and HP started picking up, I started to develop an interest in cars. Early in my "life as a car guy", I met Chuck Harmon who had a 69 L-88. I never imagined they would be able to match that car with all the hoops they have to jump through to certify modern cars - and then in 2005 they rolled out the C6 Z06 as a 2006MY. And the dyno #s started coming out. Good to be a car guy again, even if you were stuck w/ modern stuff.

Very fair point. I'd posit that stuff that was meant for the track came with parts that racers wanted, which I've said in a few posts in this thread.

I would NOT build a Q-Jet for a car that was going to live its life at Laguna Seca or the drag strip.

Not talking about the late 70's stuff. Talking about the late 60's, early 70's stuff, before CR drops and smog equipment came in.

I won't disagree w/ you that pretty much every engine offering from 72 on was, compared to the hot early stuff, crap.
Thanks.

JimLentz

It would be very interesting to take a well built Chevy BB and see shat a Quadrajet and Holley tuner could get on the dyno and what the HP/torque curves would look like.

63mako

http://www.gtoforum.com/f50/400-dyno...80/#post304184

Closest I can find. Dyno torque and HP curves are overlaid. A/F ratios almost identical.

63mako

Quadrajets were the only 4 bbl available in ANY GM car from 1965 on. The only cars GM ever built that used a Holley 4 BBL were the LT1 L88 and 1970 LS6. This was because of the low vacuum signal and being marketed as "race cars" (advertising). These where all vacuum secondary carbs also.

The13Bats

Meant for me? it didn't answer this simple question...

"Why do so many members on this forum have fine operating Q-jets on their cars performing great?

Long winded rantings do not help...

leadfoot4

I can't believe this "discussion" hasn't been locked yet....

7t9l82

#4 1970 Hemi Cuda 426 cubic Hemi 425 HP (3 Holley 2 barrles)

the 426 Hemi engine Dodge or Plymouth NEVER came with 3 2" barries "
regardless of spelling

The13Bats

Why should it be locked?!?!?!?!
People can disagree...it's okay part of the hobby, do you have any carb tech to add or just...

63mako

Hey, I told the OP in a private message, before this thread even started, to buy a Holley since he has a square bore intake installed already. That said a properly setup Quadrajet is a great street/strip carb. Try to run a 40 year old Holley with 100,000 plus miles on it and see how much work, tuning, jet changes, modifications, repair and new parts it needs to be a great carb and give you the mileage and performance the Quadrajet will give you. Have to compare apples to apples. Some guys already have the Spread bore intake, a decent Quadrajet to build, and don't have $4-500 for a carb and another $2-300 for an intake and gaskets to change over to the Holley or would rather drop the $800 on something else that will give them more bang for the buck. Telling them the Quadrajet is JUNK and only worthy of being a doorstop to prop the shop door open is moronic. True hotrodding is all about making or modifying what you have to provide the best performance possible for the least cash outlay and learning new skills while doing it.