1979 Estate Wagon, AC Blower and Carburetor Problems

[dmfconsult]

7 hours ago, JohnD1956 said:

What is that wide open throttle switch?  Never saw one of those in a Buick powered Wagon.  It would seem that when activated by putting your foot into it, the AC would shut down automatically? I wonder if this is an underlying cause of several problems.  

 

@JohnD1956 both engines listed on those pages are non Buick. Top is the Olds 403 (R, K code) while the bottom showing the open throttle switch is a Pontiac 301 (Y code). Keep in mind it’s also a 78 manual not a 79. 

 

The Y series picture was the only one showing the radial a/c compressor and associated wiring.  I guess in 78 the 403 still had the A6 compressor, although a Cali car could have been equipped differently I guess

Edited June 26, 2019 by dmfconsult (see edit history)

[carbking]

Cliff does have a significant backlog, but that is simply a testament to the quality of his work!

 

There are others that can rebuild these carbs for stock applications; but if the application is going to be non-stock, then live with it until you can live without it while Cliff is redoing it.

 

The other possible solution, since you have the book on order, would be wait until the book arrives, then give Cliff a call. Tell him exactly what you are wishing from the application. He offers the same level rebuilding kits on these last model carbs as do I on earlier ones. And he will give you excellent advice. See what he recommends, and if you feel comfortable with any necessary machine work, order what he suggests.

 

Just remember that so many carburetor rebuilders have gone out of business, and if you find one that will give you 48 hour turnaround, THERE IS A REASON!

 

Jon.

[JohnD1956]

@MrEarlWhat is this linkage for?

 

[MrEarl]

25 minutes ago, JohnD1956 said:

@MrEarlWhat is this linkage for?

 

 

JD I have no freakin idea, was about to ask you😁. Did your wagon not have one?  I suspect it may be smog/emissions related. You can’t see in the picture but it’s attached to a huge diaphragm. It’s big, ugly and in the way and would love to see it gone if possible as well as any other emission related parts that aren’t absolutely necessary. Here it is in in its full glory 

 

 

 

and this, wondering what it is too. 

 

 

I know I could probably find it in the shop manual but jeeze I’m spending so dang much time researching and trying to learn and figure s  out I never get to actually work on s. 

[NC-car-guy]

Is that linkage your cruise control?

[carbking]

According to Google:

 

17061583 = EGR valve.

 

Jon.

[MrEarl]

8 minutes ago, NC-car-guy said:

Is that linkage your cruise control?

 

I think so, the cruise control vacuum servo. Well scratch doing away with that then, it just became beautiful!!!!

[MrEarl]

8 minutes ago, carbking said:

According to Google:

 

17061583 = EGR valve.

 

Jon.

 

Thank Jon, was just about to ask if it could/should be removed but went to my second home these days and found this. 

 

http://transamcountry.com/community/index.php?topic=48142.0

 

 

 

[avgwarhawk]

12 hours ago, MrEarl said:

curious how the wire connector has that clip made into it though if it wasn't original though. I may have to fab up a new connection and if so may reroute the wiring then. Sure would like to find a 78-79 EW parts car somewhere close by.

 

I see the clip.  Possibly used to secure the wire to a hard fuel line to the carb or similar.  The only time I have seen a wire routed by the exhaust manifolds it usually connect to a knock sensor in the block or head.     

[avgwarhawk]

1 hour ago, MrEarl said:

 

JD I have no freakin idea, was about to ask you😁. Did your wagon not have one?  I suspect it may be smog/emissions related. You can’t see in the picture but it’s attached to a huge diaphragm. It’s big, ugly and in the way and would love to see it gone if possible as well as any other emission related parts that aren’t absolutely necessary. Here it is in in its full glory 

 

 

 

and this, wondering what it is too. 

 

 

I know I could probably find it in the shop manual but jeeze I’m spending so dang much time researching and trying to learn and figure s  out I never get to actually work on s. 

 

 

Cruise control top pic.  EGR bottom pic. 

[old-tank]

52 minutes ago, MrEarl said:

and found this. 

 

http://transamcountry.com/community/index.php?topic=48142.0

 

I did all that on my 76 Olds and it did not affect performance, but the oil stayed cleaner longer.

Check the timing and read the setting carefully.  My 76 has is set at 12*@2400 rpm, vs 2*@300rpm on our old iron.

When the cam was changed in mine the timing had to be set the old way:  advance until pinging at WOT, then back off...also had to use an adjustable vacuum advance to eliminate part throttle detonation.

[avgwarhawk]

11 hours ago, MrEarl said:

 

Jon, I edited the title of this thread purposely in hopes you might see it and weigh in, thanks!! 😊  I actually ordered the book a couple days ago but honestly need to get this carb off and to someone probably before I receive and have a chance to read it. I've read that the turnaround time for Cliff to get a carb back to you can be up to 12 weeks. I simply don't have that kind of time with this car as we already missed a much anticipated trip and have another make up trip planned in about 4-5 weeks. I'll be talking with Cliff and seeing what kind

of timeline and dollars I'll be looking at with him though. Thanks again for weighing in.

 

 

 

 

From all my research so far I have gained a pretty good appreciation for this carb and definitely want to stay with a Quadrejet and hopefully this one. I do need to get this car on the road sooner than later though so that may play into where it goes for rebuild. I've got a week or two of other work I could be doing to the car while it is off and being built. So will need to take all that into account.

Thanks for your thoughts and info, I really appreciate it.

 

Some pics I took today while checking for possible vacuum hose issues. I did see that I will need a new throttle cable end. Also this wagon came from California and in decoding the model # I see it is a California only carb.  Anybody have any info on what difference that might make with it.

 

 

 

 

 

 

 

 

 

 

 

 

Choke pull off is probably shot.  You can put a vacuum pump on that to check.  I would say a good rebuild, or at the very least, open and cleaning is prudent.  Replace the accelerator pump.   

[Bloo]

1 hour ago, old-tank said:

 

When the cam was changed in mine the timing had to be set the old way:  advance until pinging at WOT, then back off...also had to use an adjustable vacuum advance to eliminate part throttle detonation.

 

Yep.

 

Any car that has had the EGR removed has way too much timing at part throttle cruise. Probably about 10 crankshaft degrees too much. Sometimes you can make a stop to reduce the travel in the vacuum advance. If not you'll need an adjustable one. Vacuum should be ported vacuum from the carburetor.

 

Some cars from that era also ran the idle timing retarded. If advancing until there is no pinging at full throttle results in ignition timing too retarded at idle, then the centrifugal curve in the distributor will also need work.

 

 

[MrEarl]

Are we still speaking in English here?

[avgwarhawk]

1 hour ago, MrEarl said:

Are we still speaking in English here?

 

Rebuild the carb.  Leave the EGR valve alone.  Just make sure it is moving when vacuum is applied.  Set base timing per the manual.  Your engine has HEI ignition that is quite trouble free, however, you may look up a ignition module to keep on hand and a coil just in case.  I can say ignition modules do die and I have replaced many in this type of system.  Ignition coils have good service life.  I have not replaced many in this type of ignition system.      👍

Edited June 26, 2019 by avgwarhawk (see edit history)

[Brad Conley]

12 hours ago, carbking said:

Cliff does have a significant backlog, but that is simply a testament to the quality of his work!

 

There are others that can rebuild these carbs for stock applications; but if the application is going to be non-stock, then live with it until you can live without it while Cliff is redoing it.

 

The other possible solution, since you have the book on order, would be wait until the book arrives, then give Cliff a call. Tell him exactly what you are wishing from the application. He offers the same level rebuilding kits on these last model carbs as do I on earlier ones. And he will give you excellent advice. See what he recommends, and if you feel comfortable with any necessary machine work, order what he suggests.

 

Just remember that so many carburetor rebuilders have gone out of business, and if you find one that will give you 48 hour turnaround, THERE IS A REASON!

 

Jon.

 

 

When I checked a couple of years ago, Cliff was out two years.  It may be different today, but when I called....

[Brad Conley]

Saw your reaction, Lamar.  I know most of the others have a 2-3 month turn-a-round time.  This is a winter down time project.

[MrEarl]

 

32 minutes ago, Brad Conley said:

 

Saw your reaction, Lamar.  I know most of the others have a 2-3 month turn-a-round time.  This is a winter down time project.

 

 

 

I registered on Cliffs forum today, not accepted yet. Was planning on filling out a quote request in the morning but now wonder if there’s any need. I understand and appreciate that most folks who have carbs built through Cliff  and others in the business are likely in long term projects and can schedule accordingly. 

I’ll probably still give him a shot along with some others. I had an old school mechanic who had a shop and worked on our driver stuff for 30 or so years but retired last year. He sold the shop but retained use of his carburetor bench there and still works on carbs now and then. Maybe I’ll give him a call and see If he might be interested. 

 

 

[JohnD1956]

Why not get one or two cans of carb cleaner and just blast it while its on the engine?  Inside the airhorn, primary and secondary, and see if it becomes acceptable?  Seems you'd have nothing to lose by trying.  

[MrEarl]

Got the correct size tailpipe 90* bend this morning, cut the bent one off and installed it.

 

The rust flakes were loose in the engine side of the pipe.  I never realized how closed up it was until I was able to see it from this perspective. 

 

 

 

 

Spent the afternoon cruising the countryside and checking power, shifts and temperatures. Happy to report conclusively an improvement in temperatures. Ambient temperature 92* Top of thermostat housing 188-195. Bottom of thermostat housing never exceeded 225 where as that was where the high of 250-60 was when checked while towing. Radiator cap never got too hot to put hand on whereas before it definitely did. Transmission  pan never exceeded 195 and I kicked it down on quite a few steep hills. 

 

I really want to believe that I saw some improvement in acceleration and overall engine performance but afraid it may be a psychological thing upon having finally gotten that bent pipe replaced. It still backfired a couple times and hesitated when going full throttle from low or half throttle. The real test would be taking the Argosy back on the same roads and hills as before. 

[MrEarl]

23 minutes ago, JohnD1956 said:

Why not get one or two cans of carb cleaner and just blast it while its on the engine?  Inside the airhorn, primary and secondary, and see if it becomes acceptable?  Seems you'd have nothing to lose by trying.  

 

Maybe I’ll give it a try. I’ve ran a couple tanks of gas with Seafoam and have a can to run through the carb but haven’t made time to do it. 

[JohnD1956]

Seafoam in the gas is a good start.  But it misses the upper air horn and the throttle butterfly shafts.  

 

[MrEarl]

I know 

[MrEarl]

Sorry for the short reply @JohnD1956.  Was late and I'm a bit flustrated at finding it could take 3 months to 2 years just to get a carb rebuilt by someone reputable and with good reputation and references. I'll try the carb cleaning you suggested as well as the Seafoam thru the carb I mentioned but really not anticipating much improvement. I really think it is more in the choke or choke pull off area.

 

I'm just going to walk away from it for a couple days and get on with something else. Sorry I'm not that up on all that's been discussed and the terminology used re the Quadrajet,  hence my "are we still speaking in English" comment which confused @old-tank. But hey, y'all and YouTubes old Tylers Neighborhood Garage have taught me a lot.  Thanks everybody for your help.

 

 

[Matt Harwood]

I understand and feel your pain, Lamar. It's hard to walk away but sometimes it's good to take a break and regroup before your reserves are depleted. The answer is out there and it probably won't be anything major. But I know exactly how you feel and the frustration that goes with it. My tendency is to keep going even after my tank is empty, and that's when things get really broken. You're a better man than I to pause before, rather than after you've made a mistake.

 

That said, maybe take a different tack on this? My usual advice is to trust the factory engineers, but during this period of time they were pretty well handicapped by regulations and smog equipment that was well-intentioned but short of the technology needed to make it work properly. I might look at modifying the engine slightly with, say, a simpler, non-emissions carburetor, losing the rest of the emissions control equipment, and simplifying the engine somewhat. That could cut down on your diagnostics and improve performance, although admittedly it would be modifying the car and if you intend to show it (or if emissions testing is mandatory), that might be a demerit, although nobody will spot a different carb under the air cleaner and you can leave everything in place, just disconnected. By doing so, now you're just dealing with air, fuel, and spark and things might get easier at that point. Eliminate variables, so to speak. I have to assume the Trans Am guys have some work-arounds for the 403 and more performance, maybe tap that as a resource and see if there are simple things you can do to improve performance and maybe even solve the problem. I don't know, I'm just spitballin' here.

Anyway, I'm with you, brother. It'll turn out OK, that much I know.

[MrEarl]

Thanks for the support @Matt Harwood. Hopefully Cliff's book (which should be arriving shortly) will shed some light on not only how to rebuild to stock but also what performance enhancements can be done to make the engine perform better while towing. I purposely went with this car and the 403 and towing package over a 350 with hopes it would perform well enough to tow what it is spec'd out to tow, ie 6000 lbs (I'm only at around 4,600-5,000 at the most)  I'm doing everything else to the suspension, tranny etc to give me confidence it will perform as needed but so far the engine has let me down a bit. I really think it has to be in the carb so will not give up until it is at peak performance.

 

 

[carbking]

I came to this thread late.

 

I first read the then last part of the thread talking about Q-Jet rebuilders, which is when I jumped in, and recommended Cliff.

 

Just read the entire thread, and it appears towing is the major issue.

 

In 1981, my Dad bought a Winnebago with a 454 Chevrolet engine, and the 800 CFM Q-Jet. The Winnebago, when loaded and towing my van to swap meets, would gross 15,000 pounds plus.

 

Trying to use the speed control was an exercise in futility in the mountains of Pennsylvania on the way to Hershey. The engine simply did not have the power to pull the grades in high, as the cruise control would not engage the secondary except under WOT, in which case the transmission would downshift and the engine would overheat. Manual driving had the same issue and would also cause the engine to overheat. 

 

Dad and I finally got frustrated, and Dad asked me what to do? I told him the wrong style carburetor was on the engine for towing. He said, in no uncertain terms: FIX IT (there may have been some other words used, but fix it is a literal translation)

 

So I ordered a different intake manifold (square bore) from Offenhauser. And "married" two genuine Carter type AFB carburetors. I took a Carter 4760s (750 CFM) as the base, and replaced the manual choke with the electric choke, throttle arm, and fast idle mechanism from a Carter 9635s.

 

At the same time, I plumbed fresh air to the snorkel on the air cleaner.

 

Result: PROBLEM SOLVED!

 

Driving the exact same route at the same cruise speed from Eldon, Missouri to Hershey. Pennsylvania the following year, the travel time decreased from 20 hours to 18 hours!

 

Fuel economy changed from 6.1 MPG to 6.9 MPG (13 percent INCREASE).

 

And the temperature gauge never moved from the center climbing the grades!

 

So why did a slightly smaller carburetor make this huge difference??

 

It is important  to understand the difference between the design of a spread-bore carburetor (the Q-Jet 800 CFM), and a square-bore carburetor (the Carter AFB 750 CFM).

 

Instead of looking at total CFM, look at the PRIMARY side CFM:  200 on the Q-Jet versus 375 on the AFB.

 

The Q-Jet is a total of 800 (200 primary plus a variable 600 secondary).

 

The AFB (the one I used) is a total of 750 (375 primary plus a variable 375 secondary).

 

The extra 175 CFM (almost double) was sufficient to feed the engine under most conditions, plus the AFB could go the WOT without the transmission downshifting.

 

If one looks at many large engined trucks, one finds that a TWO-BARREL carburetor is used, rather than a four-barrel; which is where I got my idea.

 

Just food for thought.

 

Jon.

 

 

 

 

Edited June 27, 2019 by carbking (see edit history)

[avgwarhawk]

12 hours ago, MrEarl said:

 

Maybe I’ll give it a try. I’ve ran a couple tanks of gas with Seafoam and have a can to run through the carb but haven’t made time to do it. 

 

The 4GC on the 60 I removed the top. Cleaned out the garbage with carb spray.  Put in the new accelerator pump. Float level checked.  New gasket for the top and put back on the engine.  Difference between night and day when completed.  The rest of the new carb parts are still in the box.  Give it a try.   

 

 

 

[Matt Harwood]

1 hour ago, carbking said:

It is important  to understand the difference between the design of a spread-bore carburetor (the Q-Jet 800 CFM), and a square-bore carburetor (the Carter AFB 750 CFM).

 

Instead of looking at total CFM, look at the PRIMARY side CFM:  200 on the Q-Jet versus 375 on the AFB.

 

The Q-Jet is a total of 800 (200 primary plus a variable 600 secondary).

 

The AFB (the one I used) is a total of 750 (375 primary plus a variable 375 secondary).

 

 

That right there is a great view into the issue--what great information! If you're towing, that Q-jet is undoubtedly getting into the secondaries, perhaps causing the bog simply because they're GIANT. I had no idea they were so large and the primaries were so small. Everything Jon says makes A LOT of sense in this situation. The bog, the unexpectedly tepid power output, and the temperature/transmission issues.

 

Jon, could you build such a carburetor for Lamar? Are those parts you mention still readily available? Or is there a different carburetor that you'd recommend, say an Edelbrock or Holley that's available off-the-shelf today?

[carbking]

Matt - I am no longer building carburetors. Manufacture of carburetor rebuilding kits keeps me from fishing

 

The first issue here is that installing a square-bore carburetor REQUIRES changing to a square-bore intake manifold. It cannot be successfully used with the existing manifold. Period.

 

I am unaware of what manifolds may/may not be available for the 403.

 

As to off-the-shelf new carburetors:

 

Holley carburetors seem to be a favorite with many, but for some reason, Holley carburetors don't like me. Engine fires with new muscle cars (that I bought new and never touched the carburetor) and leaky Holley carburetors on three different vehicles all within 9000 miles prove this point!

 

As to the e-clone, I cannot, in good conscience, recommend one. Period.

 

But, Buick used 625 CFM square-bore carbs on the 401, and 425 in the 1960's before the spread-bore was designed. Both the Carter AFB and the Rochester 4-Jet as used by Buick. The 625 CFM square-bore are 250 primary, variable 375 secondary. Not sure 250 would be enough for the 403 for towing. It might be.

 

There was also a 692 CFM Rochester 4-Jet, but I am only aware of two: the auto choke version was used on the 409 Chevrolet and is constructed from "verypricium". The other version (which I have, by the way) comes only with a manual choke. Conversion to an auto choke would require machine work. The 692 would be 313 primary, 375 secondary. 

 

Lots of things to consider: tire size, rear end ratio, total gross weight of both tow vehicle and towed vehicle, towing speed, and engine RPM at that speed.

 

As I have posted many times, mathematics and physics are an enthusiast's best friends.

 

Jon.

[MrEarl]

Beginning to wonder if I should have have just gone with the '54 Roadmaster with a '56 322 and the McCullough Supercharger that's waiting patiently in the parts closet for it's day to come back alive. I think it and the Dynaflow in Low would have handled that hill better than the 403 in Low.  I'm being sarcastic here of course but I do appreciate the hp and torque of them 322's.  I plan to stick with the Quadrajet and get as much out of it as possible before seriously considering alternatives. After all the wagons name is SouthernBelle and I never planned to be climbing the Great Smoky or Rocky Mountains with the Argosy in tow but thing is you never know when you may encounter an unexpected 10+% grade local road.

Thanks for that great story of you and your dad Jon, really puts my dilemma into perspective. If your ever tire of fishing and want to experiment with how much horsepower and torque you can get out of a square bore carb on a 403, well I'm your guinea pig😄

[avgwarhawk]

11 hours ago, MrEarl said:

you never know when you may encounter an unexpected 10+% grade local road.

 

 

That's a fact!  Found one in western MD while driving the 54 Special.  1st gear with the 3 speed to the top.  Was no other way.  If I had a trailer I still would be camping at the bottom of that grade figuring out how to get to the top. 

 

        

[MrEarl]

The engine revin like crazy and the car and Argosy barely movin.... a real eye opener 😳

It also brought to my mind do I need a different torque converter. 

[MrEarl]

I'm contacting the three quad rebuilders to ask turnaround times for either off the shelf or rebuild of mine. So far 9 weeks from Quadrajet Power. Will have to call Cliff as he has not allowed me access to his forum yet and there is no email address on his site and as some of you know I have a problem hearing on the phone,  so will see.

 

I am also looking at the same sites to see what is available in ordering parts ie pump and choke that I could install in conjunction with an on the engine full cleaning. 

 

 

[JohnD1956]

On ‎6‎/‎27‎/‎2019 at 9:30 AM, MrEarl said:

Sorry for the short reply @JohnD1956.

 

No apology necessary.  I understand your frustration.  I really like the 78 and 79 Estate Wagons, but in my experience, they were good for their day, but never powerhouses. 

A solid vehicle can best be enhanced by sourcing older, more potent engines.  The good news is that Oldsmobile engines have so much similarity in appearance that one would never know what lies under the 2 miles or so of vacuum hoses in that '79.  😁  But an older engine will present its own set of complications. 

 

I was just about to post the comments below when you made your last entry here. But now It sounds to me like the problem lies in your rebuilt transmission.  Anyway, for what it's worth, here is what I was going to say.  ( I guess this means I did actually say it though)  

 

Jon's comments about the disparity in the primary and secondary side on the quadrojet (for towing applications) are very interesting.  And without being an engineer I have been thinking about what he said and how this might be adjusted for in your present engine.   Here are some random thoughts:

* I remember reading that the vacuum advance unit comes into play at idle to help the engine run cooler.  I do not understand why this happens, and perhaps I read that incorrectly.

* I wonder what is  the source of vacuum for the vacuum advance on your engine.  Is it ported, or manifold?  As I understand it, ported is below the throttle plates, and manifold is above the throttle plates?

* Assuming you have some vacuum when running on the primary side alone, then, if I read the vacuum situation right, the vacuum advance is in play during highway cruising resulting in a cooler running engine.   However I imagine you have much less vacuum when the secondaries are employed with loss of any vacuum advance advantage resulting in a hotter running engine.

* If your vacuum source is ported, then I have to wonder if switching to manifold would be of some correction?  

* If not, then I also wonder if prep for a towing situation should include a timing adjustment for more advance to begin with?  Of course, too far advanced will impact how it turns over to start.  

 

And ultimately I have to wonder if this vehicle would not be best enhanced with a computer controlled fuel injection application vs a carb.  

 

Naturally I have not done any research on any of this.  It is all just random conjecture...

 

 

 

Edited June 28, 2019 by JohnD1956 (see edit history)

[Ronnie]

I know you want to stay with the Quadrajet if possible but they do make adapter plates for Quadrajet intake manifolds if you decide to go with a Holly or Carter AFB.  In my opinion the Quadrajet is one of the most complicated carbs to rebuild.  They have metering rods inside that can be problematic to find the correct new ones and to install.  As you can see the vacuum lines going to the carb and the vacuum pots that connect to the secondaries are a nightmare to keep them routed correctly.  I would find a Holly with an electric choke that is suitable for your engine and be done with it.

 

Btw, how did you arrive at the conclusion that the Quadrajet was the problem.  This thread is so long and intertwined with the blower fan that it is hard to follow.

Edited June 28, 2019 by Ronnie (see edit history)

[carbking]

17 minutes ago, Ronnie said:

I know you want to stay with the Quadrajet if possible but they do make adapter plates for Quadrajet intake manifolds if you decide to go with a Holly or Carter AFB.  In my opinion the Quadrajet is one of the most complicated carbs to rebuild.  They have metering rods inside that can be problematic to find the correct new ones and to install.  As you can see the vacuum lines going to the carb and the vacuum pots that connect to the secondaries are a nightmare to keep them routed correctly.  I would find a Holly with an electric choke that is suitable for your engine and be done with it.

 

Btw, how did you arrive at the conclusion that the Quadrajet was the problem.  This thread is so long and intertwined with the blower fan that it is hard to follow.

 

The adapter plates are wonderful inventions IF one has a strong right (or left) arm, AND a rabbit problem in one's garden  They also may be used for a paper-weight (most of the time, probably not in Missouri during the tornado season  )

 

Do the math.

 

If one has an intake designed for an 800 CFM spread-bore, and one removes this carb, and with the use of an adapter, installs a 750 CFM Holley. Question? What is the effective CFM of the system???

 

Answer - less than 575 CFM!!!!!

 

You have a maximum of 200 CFM on the primary (the manifold is the limiting factor). It is probably less due to eddy currents.

You have a maximum of 375 CFM on the secondary (the carburetor is the limiting factor). It is probably less due to eddy currents.

 

My guess would be about 180 on the primary side (less than the Q-Jet's 200), and 350 on the secondary side (less than the Holley's 375) for a total of 530 CFM.

 

I will not argue that the Q-Jets are somewhat complicated. Each individual has a favorite brand, basically from familiarity. Having worked on most brands for more than 60 years, I have my opinions, but these are not truly applicable to this thread. 

 

Both square-bore and spread-bore carbs have their place, but NEVER with a spread->square or square->spread adapter plate.

 

For the record, I have three collector cars/trucks: one totally original except for the factory high performance cam,  one modified with dual square-bore carbs, one exceptionally highly modified with a racing spread-bore.

 

Jon.

[Ronnie]

6 minutes ago, carbking said:

The adapter plates are wonderful inventions IF one has a strong right (or left) arm, AND a rabbit problem in one's garden

 

In my opinion the same could be said for Quadrajet carburetors because of the complexity but I do think that when they are in good condition they perform well. I don't think they are a good carburetor for a towing vehicle. Just my opinion...     I will go along with what you say about the adapter plates and carbs. You are the expert and if you say an adapter is a bad idea then it's bad. However, I have seen a lot of people use the four hole adapters with good success. 

[carbking]

Ronnie - agree completely with you about the Q-Jet not being ideal for a tow vehicle.

 

Jon.

[NTX5467]

Mr. Earl, since you're apparently on this "binge" of sorts, call up your Buddies at Summit and have them send you an Edelbrock Performer intake and matching Edelbrock AVS2 carb for it.  Might need some automatic trans throttle linkage adapters?

 

For a towing situation, you really need a carb with 4 holes that are somewhat the same in size.  Makes the throttle more linear in action.  Rather than going from 200cfm primary to 650cfm with very little throttle pedal movement.  Or you could let the cruise control worry about that.

 

NTX5467