Is the Edelbrock 2711 and the Edelbrock 1406 a compatible replacement for a 67 330 high compression? If not, then what?
Thanks

 

A lot will depend on what else has been done to the engine. If it's otherwise factory, I wouldn't expect it to run a hell of a lot better than a Q-Jet on the original manifold.

 

What that man said.

The Carter AFB, which is what the Edelbrock 1406 was, was a peer to the Quadrajet. The former has vacuum secondaries, and the latter has mechanical secondaries with a buffered air door system. There should be no real reason to swap to the AFB. The intake would be lighter than stock and some promise 10 HP with it.

What's wrong with the 330 that it needs these parts?

 

Nothing really wrong. I have a bad oil leak at the front of the stock manifold and figured I'm taking it off anyway. As far as the Q-jet, it's difficult to tune and NO mechanic in this area anyway will touch it. They all make that face, you know. This forum is about the only place folks speak kindly of the Q-jet. Would like a bit more performance. Engine only has a few thousand miles since total rebuild. Rated at 320 hp, but I just don't see it.

 

When a Q-Jet is right it's hard to beat unless you're building an all-out race engine. The guys who won't touch them are likely long on old wives' tales and short on practical experience.

As for getting or keeping it right, I can share my own experience: I had mine rebuilt about 15 years ago and except for periodic spraying and tightening haven't touched it since and the car runs like a raped ape, as the saying goes.

If yours isn't right, there are people here on CO who can walk you through a rebuild or you can look at Ruggles videos, or there are several reputable rebuilders in North America -- a carburetor isn't terribly expensive to ship.

I would explore any of those alternatives before going Edelbrock and as I mentioned before it's doubtful you'll see any benefit from an aftermarket manifold unless you're doing a serious high performance build.

 

In my opinion, on a stock or close to stock engine, the qjet is a great, if not the best carburetor because of many reasons: good throttle response and mileage due to its small primaries and it has large secondaries for a good grunt when flooring the accelerator and for sure, on a classic car, i always would prefer the correct (and better) carb over a shiny edelbrock carb.

Tuning is not as difficult as it seems. If the engine is stock and your qjet is the right model for your engine and year, just rebuild it and verify that its equipped with the right jets/needles/secondary needles for your correct year, you should be good to go.

Assuming that thats the case, tuning is basically:

Idle mixture screws adjustment (quite the same procedure as on every carb)
Hot slow idle adjustment
Fast idle adjustment
choke adjustment (make sure its completely open when engine warmed up)
Secondary air door spring adjustment (shouldnt be too loose, this leads to a lean bog when flooring it).

In this forum is a lot of good information on Qjets and adjusting them and there is plenty of information on the correct numbers/ jetting in relation to make, engine size and year on Qjet-specific shop sites. Also, you can find a lot of how-to-videos about rebuilding a Qjet on Youtube.

hope that this helps!

 

You won't see any difference with the intake, and unless there's something REALLY wrong with your carburetor, the E-Brock carb won't make a difference either (QJet is 750 cfm, E-Brock is 600 cfm). Plus you'll have to tune the new carburetor for your engine.

 

Here's something that may make a difference: are you planning on using headers?

 

Yes they’re difficult to get a flat fuel curve out of and very sensitive to fuel pressure as well.
Everyone has heard me say this a million times, but buy a wide band and tune it right, whatever carb you choose.
Case in point, I dyno’d another builders 455 a couple weeks ago. The owner sent the carb to a rebuilder, who told him “it’s right for your year 455”. It ran so lean on the primary side that I had to go up eight jet sizes just so we were in the safe zone. Buy a wideband.

 

What all was done in the rebuild? Stock pistons and cam? What trans do have? As said, any carb will need tuned to your motor. Consider the new AVS2 carb over the base Edelbrock carb. Also the RPM intake is a better intake than the regular Performer.

 

the 2711 is a nice choice intake for the 330. it’s smaller high velocity , longer separated runners are good for the 330.

same with the 1406. it’s easy to tune and will work good on the 330.

there is no need for modifications to the motor

 

So all he needs to do is slap on the 2711/1406 combo without doing anything else to the engine and he'll get noticeable gains? Ballpark, what kind of improvement might he be able to expect?

 

If the car is an automatic with a functioning Switch Pitch converter and you change the carb make the linkage continue to work the Switch Pitch or you may lose more driveability than you gain.

 

slapping it on to the engine will improve low and mid range TQ , widen the power band and improve the fuel mileage. it improves the vacuum signal to the carb

it will not magically fix all issues with a poorly rebuilt engine or any other engine with problems

That intake is truly a bolt on improvement on stockish type engines.

 

You have to remember that there has not been a carburetor installed on a stock vehicle for close to 35 years ? Most guys working in shops were not even born yet so I don't think its fair to think negatively about them if they don't want to fool with a carburetor.

As far as difficult to tune goes it is no different than any other carburetor other than the fact that you have to take the top cover off to change metering rods and jets. Pretty sure you have to do that on the Edelbrock also.

If you are going to depend on a shop to do the tuning I think you are in for a disappointment because there are very, very, very few that can or will do it. You are going to have to learn to do it yourself.

And I hate to say it but I don't personally think you will see much real improvement with the intake and carb swap. If you engine was rebuilt 100% stock then I would certainly stick with the Quadrajet. If it has been modified then there are a few guys around the country that will build your Q-jet for your application BUT it is really hard to get a carb exactly right on the bench. It still might need some tuning.

 

It's a scientifically proven fact that Holley carburetors are shinier than Edelbrocks.

Really, what ^^^THEY^^^ said.

 

Interesting. Thanks! Can you quantify (in an estimate, of course) the potential improvement on this type of engine? Ballpark 1/4 time/MPH difference from baseline, maybe? Might give OP an idea of whether or not it's worth doing.

 

here’s the difference between stock and the performer on a 350 that had headers. TQ and HP was better through the whole range to 5,500. 20+ on the TQ and about 15+ HP

Dotted lines are Performer

 

Be interesting to take the headers out of the equation. OP has yet to tell us if he plans to use them or not. Hell, he might not even have dual exhaust!

 

Why the squiggles from 3500-4500?

 

Dale is there any advantage to the 2711 non EGR to the EGR 3711? Suprised it is that much over the stock intake.

 

Can you elaborate on what “stock” was in this scenario? As in what year engine was used?

 

1970 310hp small valve

 

Edelbrock claims more than 20hp advantage over stock on 350 with mild cam and headers.

they do work good on stuff with not much rear gear . I’ve used a a couple on trans ams because they needed to work with the hood scoop.

 

better looking for one..same port specs and you won’t have to block off the egr valve. I drill and tap the plenum holes for plugs

 

Okay, well it sounds to me like OP will want to use headers along with a cam upgrade to take advantage of the 1406/2711 combination.

 

Yeah, I have a 3711 here, just curious if any other changes were done as the 2711 came out many years later and is more money new. Wasn't it released because the Edelbrock carbs didn't clear the EGR port? Also at what point does the RPM make sense to swap too? Guys have gained at the track over the A4 on factory Vin 9 307's. Another former member gained with the RPM over the Performer on a 9 to 1 350, fairly mild, 214/224 cam, I believe. As mentioned the small runners would help especially with tall gears and a lower stall converter. If I do use my 3711, it will go on a truck application with EGR and a 454 TBI and the 1" factory 4 barrel to TBI adapter with a custom tune. The Edelbrock test is one thing, Dale doing a separate test showing a gain across the board is surprising and a nice gain.

 

[QUOTE=CANADIANOLDS;1599734]Edelbrock claims more than 20hp advantage over stock on 350 with mild cam and headers.
/QUOTE]
Why the squiggles on your dyno graph? Was it the brake or maybe the secondaries coming in? Curious.

 

[QUOTE=cutlassefi;1599761]Don’t know. Could have been from sensitivity filtering or smoothing differences when using the dotted for the different layover.

if it was switched, the same more jagged dotted graph would show up for the other combo. the broken line choice always did that with all engines. this is old superflow

 

the rpm is a great manifold too. engine size and expected rpm would be what would make the manifold choice

smaller cubes like 330 and 307 would usually be better off with the performer for the street unless you got a 4 speed and lots of rear gear.

or in bigger cubes with highway gears , the performer is the better choice. in the trans ams I used them on, they made fantastic off idle TQ and pulled like a diesel with an automatic , 2:41’s and mild 403’s

 

[QUOTE=CANADIANOLDS;1599770]Gotcha, ty.

 

Quote:

Originally Posted by CANADIANOLDS

Edelbrock claims more than 20hp advantage over stock on 350 with mild cam and headers.

I can believe that overall, but I have to wonder how much of that gain comes from the larger camshaft. We know the factory 350 cam is absurdly conservative, so just installing their .448" lift 204º duration cam would give a large gain in power.

 

for you, I think it’s best to stay with the stock iron intake on anything you have.

the stress of trying to figure out why it’s better isn’t good for your health

 

Apparently you’re a blind comedian.

 

your slug would run quicker, be more responsive and get better mileage with the small runner performer.

then the Fun71 would be real

 

You mean like the one he lists in his signature?

 

It is the RPM in his signature. Dale likes velocity, look at his 307 builds. The SP2P intake I got from him years back was the ultimate version of that. The Qjet was too much for it, the small GM TBI would lay rubber with it. I went to the A4, didn't really gain anything. I should have put on the Performer apparently.