Carburetor replacement recommendation?

[71 UK Vette]

My Q-Jet ('71 350/270) has bit the dust and is evidentally beyond a rebuild (spindles). The car is very original and I am reluctant to change from stock, however, I am based in the UK where Q-Jets are a long wait, expensive, and rebuilds only. Everyone I speak to recommends dumping the Quad & switching to an Edelbrock or Holley.
Can anyone offer suggestions, in particular as to which aftermarket carbs I could use that would 1) have electric choke and 2) not require me to change from my stock intake manifold?

 

[ratdog]

Fix the Q-Jet, there is a place or several here in the US that can refurbish that beast. Holleys are junk compared to that Q-Jet, plus keep your car original. Just my 2 pence

 

[Stallion]

What's the idea behind the Q-Jet? What makes it that much better than all other carbs? How many barrels? 4?

 

[ratdog]

Stallion, what does the prefix quad- mean? That is how many barrels!

 

[Stallion]

http://www.ecklers.com/product.asp?dept_id=1269&pf_id=28913&mscssid=V90TMWBA9WSR2L0J00N0SM2EPK224FPD

I found this at ecklers, but this doesn't seem to be your years ('75 - '79). But this is a Q-Jet.

 

[Stallion]

Stallion, what does the prefix quad- mean? That is how many barrels!

Of course! 4!! How many barrels are you average carb, though? Just 2, maybe?

 

[ratdog]

In my opinion, which isn't accepted much here, a Q-Jet is more likable than a Holley. Holley's are finicky, just my 2 barrels worth

 

[ratdog]

Most small are 2, some v8 novas had 2, most are 4 though

 

[vigman]

Pro's & Con's

1) The Q jet is a good carb..It's just a tad difficult for people who do not work on em everyday to understand. If your spindles are bad ( read throttle shafts).. just have the lower plate replaced.IF YOU DO NOT HAVE ACCESS TO A MACHINE SHOP!

Many good machine shops here (stateside) will remove the throttle butterfly shaft.. drill the base out a tad and re bush the base.. so no more sloppy spindles.

Make sure they epoxy the press in plugs at the bottom of the fuel bowl (2 places).. they ALWAYS leak there.

2) If you decide on the Holley you WILL need a new manifold to optimize the fuel flow.. you old one will work.. but it's not quite proper.

SAVE YOUR ORIGINAL PARTS !!!!!!!!

The Holley might be a better way to go for YOU.. since the parts might be more available on your side of the pond.


My vote is the Q jet repair.. the further away you get from stock.. the more of a bodge the new install will be.


Vig~

 

[vigman]

Quarda-Jet

Is 4 barrels

2 small ones for the primaries ( for good gas milage)

And two BIG HONKIN ones for the secondaries.

It's roughly 750 cfm at WOT. The secondaries are Vacuume controled so they will not open if the engine doesn't need em.

It's actually a simple carb.. that has proved itself over time... But it has NO sex appeal..

I have never seen a ROCHESTER sticker! It's not AS quick to service as a Holley ( as in race applications )... and you find em in just about EVERY pre 79 GM product.. and there were MILLIONS of em around, doing the daily work

Go to a wrecling yard pay 25 bucks for one.. and tear it apart for the learning experience.


Vig~

 

[ratdog]

Vigman, eloquently said....................................

 

[71 UK Vette]

Me again.
1) Are Quads stamped, i.e. would replacing the carb with a 2nd hand unit mean the non-matching numbers?
2) I note Ecklers does sell two replacements: a Quad rebuild, and an Edelbrock direct replacement. Any experience of either?

 

[ratdog]

I have a 69, they are stamped as to what carb is correct for that car, I don't think they have a vin match on them. I just remember each layer had the model # on it for my application 427/390

 

[Jack]

edelbrock Qjets 1901 & 1910

71 UK Vette:
I recommend staying with a Qjet. If repairing yours is not feasible or a rebuilt/good used Qjet is not readily available ... you DO have another Qjet option. Weber/Magneti Marelli is the current licensee for Qjet and manufactures NEW ones ... Edelbrock markets the NEW Qjet that's made by Weber/Magneti Marelli. It is a true clone of the original Qjet.

Please note Edelbrock markets TWO entirely different carbs for chevys ... one is a clone of the Carter AFB carb and it is series 14xx. This is NOT a Qjet.

Your original Qjet probably flows about 750 cfm.

The series you'll be interested in for Qjet replacement is Edelbrock 19xx. These ARE clones of the Qjet. There are bascially three Qjets within the 19xx series. The 4MV flows about 750 cfm ... the M4M flows about 795 cfm ... the RPM (a hi-po version) flows about 850 cfm. The Edelbrock part number you'll probably need for direct replacement is 1901. The 1901 has a choke on it just like what came on your 1971 vette ... it is NOT an electric choke. The 1901 is aka 4MV but is pn 1901. There are other Edelbrock Qjets that do have electric choke ... the M4M pn’s 1904 and 1906 have electric chokes but their throttle linkages are newer style & different from that on your 1971 vette. Finally the RPM (hi-po 850 cfm) pn 1910 has throttle linkage like what is on your 1971 but does have an electric choke.

With ANY of these ... you may or may not need to rejet/tune.

So ... it seems if you want to stay with original style choke the 4MV 1901 is for you. But if you choose to go electric the RPM 1910 is indicated.

JACK:gap

 

[JHL]

Hi

When I bought my vette it had a Holley which I have never been very keen on so I replaced it with an Edelbrock manual choke. Straight out of the box and on the car and it ran great. No more leaky fuel bowls either.

They are readily available from almost any UK American parts supplier for around 250 pounds. I bought mine from John Woolfe Racing along with all the other Edelbrock parts. If you should decide to go that way then give them a call, not the cheapest but they were very helpfull and knew their stuff, ask for Tim.

J.

 

[vigman]

The stamp is in the upper air horn

( the top metal bit)

You could send the entire carb to Ecklers.. they do full restores on the one you provide

( take pictures of your numbers & tags before you send it)

Do you have the metal tag still on yours ( the tin bit hanging on a screw).. save that.

The carb I believe only has a date code on it.. not an actual serial number.


Vig~

 

[SwaveDave]

I elected to go with an Edelbrock 800 for my BB . This carb is simply great. It was almost perfect right out of the box and you can easily change the jets and metering rods from the top without disassembling the carb - its a 5 minute job. Ive tried Holley and Speed Demon carbs, but, the Edelbrock is my favorite for simplicity .

 

[Stallion]

Re: Hi

When I bought my vette it had a Holley which I have never been very keen on so I replaced it with an Edelbrock manual choke. Straight out of the box and on the car and it ran great. No more leaky fuel bowls either.

They are readily available from almost any UK American parts supplier for around 250 pounds. I bought mine from John Woolfe Racing along with all the other Edelbrock parts. If you should decide to go that way then give them a call, not the cheapest but they were very helpfull and knew their stuff, ask for Tim.

J.

When you say a "manual" choke, this isn't an electrical choke? Mechanical? What are the reasons why you wouldn't go electrical for the choke in the carb? Isn't it more efficient and need less maintainance (sp?)?

 

[SwaveDave]

Stallion,

ALot of people elect to go with a Manual (mechanical) choke because they dont stick as many electric chokes will / you can adjust the amount of air the carb gets during warmup and could go wide open on the choke sooner (theoretically) / and-or....it allows you can use a deeper drop base (for the air cleaner) for the carb if the automatic choke mechanism isnt in the way. These are some of the reasons .

I ordered my Edelbrock Carb with the manual choke and took it completely off with the accompanying hardware , since its a summer car anyway. When i fire it up first thing, i keep my foot on the throttle for about 20 seconds , then release it , and it maintains about 700 rpms . Plus, i can take a bit more air into the carb with no choke plate on the top of the carb.

Dave

 

[Stallion]

But with maintaining of a higher idle, wouldn't that mean less fuel efficiency? Or no? Because that manual choke sounds to be the best way to go by the way you talk about it.