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Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: 63ConDan ()
Date: June 05, 2018 03:27PM

Hi Looking to change out a leaking center mounted 4 Brrl with no low end off a good running 140, to something different. 4 Brrl is 640 CFM, and is from 1971.

I would really like 2 newer modern 2 brrls, or 2 TB's with modern features, but still use all 4 of the 140's intakes.

Let me know your thoughts and what known available part could be used to make this work. I m ok with new, but will work with good used too.

Thanks in advance.

Dan Central MN

1968 Convertible

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: MattNall ()
Date: June 05, 2018 05:35PM

If you have the room buy an adapter plate and run a 300 cfm 2bbl

reman $135 no core


Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!

Edited 1 time(s). Last edit at 07/13/2018 12:33PM by MattNall.

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: solo2r ()
Date: June 05, 2018 06:20PM

Get a pair of stock carbs and linkages [or maybe Roger Parents awesome linkage]. Hook up the chokes and be done with it!

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: chris ()
Date: June 06, 2018 06:14AM

There have been some who mount a Holley/Weber 5200 (I think) on each head. Clark's used to have a setup for that but it only fed one intake hole on each side. Not sure if you could find or make an adapter to allow each one to feed both holes. I think having all four holes open seems to help midrange, but that's far from scientific.

'65 Monza 4 door
4 speed
Gardner, KS

Heart of America Corvair Owners Association

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: j3m ()
Date: June 09, 2018 10:31PM

Too gigantic of Venturi & carb's CFM rating will usually kill low end.

In Minnesota it gets chilly in both April and October.
It isn't the same for someone running a center mount in Los Angeles, or San Diego, or Miami, Tampa, or even Jacksonville Florida.
Carb icing is likely during chilly weather.
THE OTHER HUGE ISSUE THAT YOU'RE GONNA HAVE IS THAT YOU'RE GONNA HAVE TO REALLY GOOD AT FABRICATING AN EXCELLENT THROTTLE LINKEAGE. It seems routinely simple but that linkeage has to function perfectly each and every time,

If you're gonna try something with some carb, find something rated 390 cfm or SMALLER. You're gonna have to find something that can be jetted SMALL enough to work okay with CORVAIR's engine requirements. Make certain that the Venturi size isn't any larger than 29mm.............convert that mm measurement for the approximate INCH sizing.
There are quite a few carbs that might work, BUT IT WON'T BE A SIMPLE PROCEDURE OF JUST bolting it on or modifying an adapter to allow it to bolt on...
If you get too far outta wack with what a CORVAIR engine needs to function decent enough, then you just begin to have to "re-invent" everything and UNLESS you have significant experience in FABRICATION and MODIFYING CARBS such as someone with years of low buck oval dirt track racing or off road racing,'ll be screwed for about two to six months until you figure something out (the right combination..) that works decent enough. Now, having said that, if you opt to go the cheapest/free used piece of crap old carb that you can locate because it costs nothing, you WILL not find an acceptable solution because without REBUILDING/REJETTING/MODIFYING any such carb so that it is "tailored" more for the CORVAIR, than whatever hulk it was the original application for.
Nobody is saying don't Tinker and Macgyver if you want to. That is how all new alternative set-ups are born. If you don't know enough about what you're attempting to do, the chances are very great that your first attempt will NOT be an acceptable solution. You'll learn something possibly and might possibly through trial and error be able to dial in the carb's jetting and re-curving the distributor such that your combination is a WINNER. This assumes that the carb linkeage design is excellent and the carb itself is perfect functional order, and not some old, leaky piece of trash that hasn't been rebuilt to the highest quality standard.

THERE ARE SEVERAL REASONS THAT MOST PEOPLE NO LONGER TAKE THIS TYPE OF CARB APPROACH. Why bother when there is a superb simple bolt-on solution that beats the best ever carburetor solution whether it is the factory oem carbs or any other alternative carb set-up. YOU CANNOT BEAT EFI. You can try but all that is going to do is waste your money and time until you finally see the light and realize for yourself that EFI is the way to go.
Various people have taken the aftermarket Centermount intakes and even the factory turbo crossover intake and used those to adapt some EFI set-up.
Think for yourself if you really want to or just purchase a superb design that just bolts on and is marketed by CLARKS, the world's best Corvair parts supplier.
Never say it can never be done, as time and again, folks here on Corvaircenter have come up with functioning set-ups that most folks said would never work at all. Depending on your current knowledge and dedication to learning the how/why and extensive study of others' successful set-ups, you might get there sooner rather than later or never at all.
I think there are significant reasons to eliminate the distributor, and the mechanical fuel pump, and the carbs and go with computer controlled efi/dis.
Perhaps you should read some of the many efi threads here and the comments/technical details/durability-reliability details as provided by those designers of EFI set-ups for the Corvair, past and present.

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: kmart356 ()
Date: June 10, 2018 04:12AM

Another excellent option is the Weber 38DGES - 27mm venturi - 380cfm. Adapter plates available. Or a progressive Weber 32/36

'62 Spyder Coupe

Edited 2 time(s). Last edit at 06/10/2018 04:18AM by kmart356.

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: vairmech ()
Date: June 10, 2018 07:06AM

Just get yourself a SBC Quadrajet and be happy. Small primaries means good drivability. The secondary top butterflies need to be cranked a little tighter but that is the simple solution. Even better than the Holley 390! You will still need a spread bore adapter for the Quadrajet.

Ken Hand
Handy Car Care
248 613 8586

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: strangecars ()
Date: June 10, 2018 09:15AM

This one is for sale. $175 plus the ride


Steve Morton
1961 Rampside, 67 and 2 1964 Monzas

Morton's Classic Garage
Parts and Service
Nampa, Idaho 83686
30+ parts cars

Edited 1 time(s). Last edit at 06/10/2018 09:15AM by strangecars.

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: Lane66m ()
Date: June 10, 2018 11:27AM

If you had acted quickly, you could have had the 4 carbs and linkage for that measly $200. That was a great buy.

I have 4 140 carbs and all linkage I would consider selling. Carbs have to be rebuilt as they went through a hurricane and a long period of no proper storage. Linkage looks like new as I rebuilt and painted it.

Al Lane
Ellabell GA

1966 Monza Coupe, 110 hp, 4 Spd
1968 Camaro SS Coupe 350 CI 295+ HP PG
1964 Greenbrier Deluxe, 6 dr, 80 hp car engine, PG
2015 Chevrolet Malibu 2LT
2018 Chevrolet Silverado LTZ Z71 Centennial Edition
1947 Farmall A tractor 15 hp

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: roger65180 ()
Date: June 11, 2018 05:17AM

do what Ken/vairmech said the GM QJet will work the best for a center mount, J3m is correct on his words of wisdom also , the throttle linkage must work well to be happy. and FI is the best of all however expensive . if you go with the Qjet you will want the 750 cfm small block carb ,do not worry about going up in carb size the primaries are small and the secondaries are variable it will only feed what the motor will want

Roger R
Madison Wi
62 ct pg turbo
65intercooled 180 4sp,autocrosser
62 Rampy

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: Gregory_Miller ()
Date: June 12, 2018 08:55AM

My dad put a Holley on our 68 140 way back in the 70s. The "linkage" was a cable that frayed and broke way too often right at where the bellcrank under the back seat exited the tunnel, and with the icing and other issues I was happy to go back to stock primaries only since the original 68 140 set was long gone. Just my opinion and your mileage may vary.

Greg Miller
Eugene, Oregon

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: j3m ()
Date: July 13, 2018 12:21PM

Now this is in no way an endorsement for going backwards to carb-Land when there is so much on the World Wide Web showing how resourceful folks using Boneyard-Pick and Pull Parts, Replacement parts from FLAPS, and parts sourced from EBAY and other avenues, make outstanding "homemade" programable EFI set-ups for their vehicles.

As to the linkeage, in my best Jethro Bodine voice, "You Ain't Gotta Throw Away Everything And Re-invent The Daddgumm Wheel, Because You Already Done Gots That There Original Chevy Corvair Throttle Rod That Enters The Engine Compartment. Shucks, You Just Build Offa Whatcha Already Done Gots Right There. attach a
( U shaped ) piece to the end of the Throttle Rod..........Connect a Braided Steel threaded throttle cable to that......... You'll First Need To Construct a RIGID ANCHOR attachment point THAT EITHER mounts via threaded studs being used to Bolt Down the LEFT SIDE(driver side) aftermarket Centermount Intake,
(or if you're using an old Modified TURBO CROSSOVER intake as a Centermount...), the RIGID ANCHOR attachment point could either possibly be some solid angle iron piece that is cut/shaped/ground/with holes drilled in its base so that it BOLTS on top of LEFT SIDE base mount of the aftmkt/or Turbocrossover intake, VIA THE THREADED STUDS THAT YOU'LL BE USING INSTEAD OF BOLTS To hold the Left side of the Intake down. .........An alternative way to Construct a RIGID ANCHOR attachment point for the threaded BRAIDED STEEL throttle cable to anchor and bolt to IS TO WELD A STEEL GUSSET on the far LEFT SIDE OF THE INTAKE just at the point that that Left side tube of the INTAKE begins to Curve like the ST LOUIS ARCH.......yeah weld a "sail panel like"-GUSSET beneath the LEFT SIDE intake tube curve...............DRILL A HOLE IN THE GUSSET THAT MATCHES THE Threaded Braided STEEL THROTTLE CABLE........obviously, doing it with a welded sail panel like GUSSET, it must be solid and RIGID and must not exhibit any significant flexing at all when the engine bay is at its hottest.
................ALL OF THIS METHOD OF USING THE ORIGINAL THROTTLE ROD ASSEMBLY FROM the pedal to its ending point Inside the ENGINE BAY, is HIGHLY DEPENDENT ON YOU REMOVING ALL SLOP AND MAKING CERTAIN THAT THE INTEGRITY OF ALL THE COMPONENTRY BENEATH THE CAR IS BETTER THAN is not that hard to make certain minor improvements there that eliminate slop and improve the integrity and operational function.............
Now, if all this stuff seems far too complex, and it thus far is only Jethro Bodine, basic "carpentry".......YOU MAY NOT BE ABLE TO HANDLE THE TRUTH THAT A CRAPPY DESIGNED LINKEAGE is exponentially worse , no matter if you succeed in finding the world's best carburettion for the Corvair. The original Corvair linkeage from pedal to carbs is after all designed by engineers and would not meet the definition of CRAPPY as defined here! An operational linkeage can look like the north end of a southbound mule, or worse and still be operationally functional and decent enough if like the Timex watch can take a licking a keep on ticking without any problems. The other side of the coin is that ANY PIECE of your Do It Yourself Linkeage equation CAN RUIN the Functionality of an otherwise beautifully assembled nice looking "masterpiece".
Everything has to just work flawlessly everytime and that is a helluva lot easier to say than do.
It is not impossible. Low Buck Racing, like those intense but thrifty cats that race in MINI STOCKS, the racing classification that has been dominated by ancient FORD 2.3 liter (PINTO ohc) and the ancient TOYOTA 3TC 1.8 liter (Corolla ohc "hemi') both engines date to the early seventies as the 3TC is just the 1.8 liter version of the previous 1971-1979 2TC that displaced 1.6 liters......3TC was in the 1980 - 1982 Corolla..........FORD 2.3 was seen from 1974 to the early nineties.
In case you're wondering, those intense thrifty cats make power that you would not believe from such ancient engines, and these engines HOLD UP to the almost 7000 rpm that they are winding them out to. They are slaying all competitors trying to use more modern powerplants as allowed within the rules.
Pound for pound, that very lightweight "hemi" 2tc/3tc TOYOTA four cylinder is better than the PINTO 2.3 ohc but that FORD 2.3 is very capable and parts are easily found and ridiculously inexpensive, and much is common knowledge to unleashing the power from both these ancient powerplants while delivering durability that is unimaginable considering such Old Technology.
Now, what does all this have in common with Corvair folks wanting to MacGyver some solution using OLD TECHNOLOGY. There are your kindred souls doing essentially the same kind of thing with really ancient stuff. Yes, the RACING ARENA is the proving ground for durability and what actually works and holds together. Think of these Mini Stock RACERS as MacGyvers like the MacGyvers of Corvairland, with the one distinction that Corvair folks are more like Uncle Jed in intellectual reasoning..(DEFINITELY NOT LIKE Uncle Jed in their bank account...).......while the Mini Stock RACERS tend to be more like JETHRO in their educational smarts, cyferrin' skills, and their ability to react and adapt like a double naught spy..
That is what makes for some of their "breakthroughs", the crazy mixture and conglomeration of inexplicable parts that only JETHRO might envision assembling, comes together once in that rare blue moon but when it does you can here JETHRO yell YEE-HA all the way from Beverly Hills to Bugtussle to Hooterville, Silver Dollar City and beyond.

from this thread

MOTORCRAFT carb CFM ratings (based on the Identifying casting which I think may provide the Venturi size in inches)

0.98 = 190cfm
1.01 = 240cfm
1.02 = 245cfm
1.08 = 287cfm
1.14 = 300cfm
1.21 = 351cfm
1.23 = 356cfm
1.33 = 424cfm

I don't know if that info will be at all helpful but it gives some indication of the sizing of a 2 bbl Motorcraft carb that you may find in the "wild".
If nothing else this highlights the IMPORTANCE of doing some Columbo investigating on any of the makes/models of carbs that you may be considering...
................JUST ONE MORE THING, SIR....I Gotta know more about this (fill in the blank, make/model) carburettor.
RESEARCH and ASK QUESTIONS on various sites and forums
You might just see how one person did something that might just make life easier for your Corvair application, even though that person's build and donor engine is nothing like the stock Corvair that you're using.
You just never know, until you know it. Don't give up if you wish to do it with outdated technology. Money is better spent on EFI or at least going the Roger Parent linkeage and the best possible rebuilder for the oem Rochesters along with elec fuel pump and the best dizzy and ignition combo to compliment the oem Rochesters.
Above all, have fun doing what you want to do. The worst case scenario is that you spend money and time and the results are less than you expected.
You will still learn something and the price of an education will probably be worth it as you'll learn something that will help you other non Corvair related automobile projects and possibly on future Corvair projects too.
If you're okay with the possibility that like investing in a tech stock without mature quarter versus quarter earnings....just the prospect of becoming profitable at some might not do so well, but as some say, without taking the risk(accepting the challenge)..........
......You might just want to stick with the best EFI option for the nearest "guaranteed" expected results.
Have fun with your projects. If you have fun with it and you learn something and it brings you joy, the money and time are secondary. Who knows.., you might come up with something decent enough. If nobody tried to do something just a little wacky, there never would have been the improvements that the Corvair has seen....... improvements to many other cars too.

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: Gregory_Miller ()
Date: July 13, 2018 01:01PM has an EFI system that I am slowly working towards. Check it out, it uses all 4 holes with a non-progressive linkage system. I believe Roger Parent is working out or has worked out the geometries to make all 4 carbs open in unison with his linkage kit too. Check it out. All it takes is money. smiling smiley

Greg Miller
Eugene, Oregon

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: 63ConDan ()
Date: July 14, 2018 07:45AM

HI To follow up on this: Did look very close at 2 2 brl weber carbs. To much variability and seemed fussy too. So did have the current carb rebuild it is a 750 CMF quadjet and getting that installed. So I'll share results once running.

Thank you for all the feedback.

Dan Central MN

1968 Convertible

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Re: Part Wanted Carbs / Intake/linkage/ Ideas
Posted by: firevair66 ()
Date: July 14, 2018 02:04PM

Fairly simple linkage mod. without doing anything to stock parts.

John Shoemaker,Riegelsville,PA.
1958 Impala Sport Cp. 348 ,pg/ac
61 Rampside full custom show truck
65 Monza 110/4 vert driver
65 Full Custom Monza 140 Cp
66 Monza 110/PG Vert
66 Corsa FITCH SPRINT Documented ( in Process,recondition)
66 CorV8 350 "firevair"Custom Show


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