New member finishing inherited project

[6T5VAIR]

Hello everyone.

My father purchased a 1965 Corvair Monza in 1992 and started work on it immediately.

Decades later, in his advancing 70's, after two moves including one from US to Canada, work slowed and finally stopped.

While he was in the hospital in November for what turned out to be stage 4 cancer, we talked about the project. He said it needed only bodywork, carbs done, and a few minor things to be completed.

Knowing how much work he had already done, I decided to try to finish the project for him hopefully in time to take him for a ride in it.

Unfortunately the cancer won that race, and he passed in February.

This weekend however, the car made its first voyage under its own power since the 80's. It though I would share some pictures with the group.

Once I get it detailed, finish tuning the carbs, deal with a few minor issues, and trailer it home, I will do a proper photo essay.

Meanwhile... "Hi"... I'm Russ from Ottawa, Ontario, Canada. Good to meet you all.

[fred bagnall]

Nice car. Welcome to the group. I think you will find this a very friendly and helpful community.

[Phil Dally]

WELCOME!!!

Looking like a bit of a Hot Rod.

[cnicol]

Welcome and good job! Sorry about the loss of your father.

I'll note: Mounting the choke pull-off on the secondary is a cool solution. It gave me a double-take as it looked like your primary was in the wrong spot.

[6T5VAIR]

Expand on that? We had some confusion figuring this out and may have made a bad decision…. The rearmost carb on the right side is the primary right now, the frontmost carb has the linkage to delay throttle actuation and has no pump.

Unfortunately I did not get any sort of handoff on the project so it often involves thinking like an engineer to decode what was done.

I have a lot of notes on what was done but not often why.

[cnicol]

Ok...

I see the choke mechanism on the right-front carburetor. This makes it the primary so it has idle circuits, transition, and accelerator pump. This one needs to operate directly with the diagonally-opposite primary and the accelerator pedal.

Your right rear carburetor is the secondary (with a cleverly attached remote choke pull-off). This is the one that's supposed to have delayed application at say 2/3 throttle.

If you have the right-rear (Secondary) set up to run with the opposite primary and accelerator pedal, the engine would have very poor idle and off-idle progression. The linkage would need to be redone to link the diagonally opposite primary (choke equipped) carburetors together.

I'm sure you know your carburetors have all be rotated 90-degrees from stock and that's what's throwing you off as there's very little if any documentation for this modification. The mod is supposed to help with cornering during race-track use.

[RexJohnson]

On my first car I rotated the carbs 90 degrees and I also had to remote mount the chock pull off. The throttle linkage ends up right where it would normally be.

[toms73novass]

Sorry to hear about your father. With the Vair you have a special part of him you can cherish. I have a few of my uncle's cars that passed and one I have is name on a a remembrance.

[cnicol]

You wrote: "Expand on that? We had some confusion figuring this out and may have made a bad decision…. The rearmost carb on the right side is the primary right now, the frontmost carb has the linkage to delay throttle actuation and has no pump."

Craig asks: Are we / Am I being confused by terminology here? We here in Corvairland use "front" to mean "front of the vehicle". If one adapts that standard, your sentence above becomes:
"The FRONT carb on the right side is the primary right now, the REAR carb has the linkage to delay throttle actuation and has no pump."

If that's what you meant - that linkage situation is correct and the world can again spin on its axis.

[Richard]

The picture below from Clark's looks the same with right front as normal Primary position, with same linkage.
It looks in photo from 6T5VAIR that vacuum advance is connected to Ported Advance port on Secondary carb, which would make it ineffective in cruise.

[66vairguy]

Some good comments.

Your carburetors are rotated 90 degrees compared to factory. This modification was claimed to keep the carburetors from flooding in a high "G" turn, think racing. Not sure how well it worked. Now some install tubes to rise above the float vent holes to keep gasoline from slopping out of the float bowls into the venturi when racing.

Orientation of things in a Corvair is tricky. I never use RIGHT or LEFT. Passenger side or drivers side orientation is absolute (unless you are driving a U.K. or Japan car - LOL). As suggested use FRONT OF CAR, not front, and REAR OF CAR, not rear. Since the Corvair engine is reverse rotation (vs. std GM front engine cars) and the engine is turned around - well saying front or rear of engine is often confusing.

Passenger side the primary carburetor goes toward the front of the car. Drivers side the primary goes toward the rear of the car on a factory car.

Good picture by richard. Shows primary linkage on passenger side toward front of car, yet the choke vacuum pull off is mounted on secondary toward rear of car with a long rod making the connection.

You have an interesting car. Good luck with it.

[RexJohnson]

In 6T5VAIR's picture the vacuum advance is hooked to the ported tube. It and the chock pull off hoses cross at that point and makes it hard to see. The vacuum advance hooked to manifold vacuum would not make it ineffective at cruise it would just be active at idle. The Corvair engine turns the same rotation as a SBC it is just driven from the front. Just not many cars do that. The Cord comes to mind as a car that was driven from the front of the engine. An old VW would also be driven from the front but it rotates the opposite direction.

[Richard]

>>The vacuum advance hooked to manifold vacuum would not make it ineffective at cruise it would just be active at idle.<<

During cruise the Primary carb would be at part throttle and the Secondary carb would be completely closed or just cracked. I've never used carbs with mixture screws as Secondary carbs and have read different things. It looks to be using ported to me.

[6T5VAIR]

Ok let me reset a bit, there may have been some errors above on my part.

Right now, drivers side rear of car carb is primary, passenger side front of car is primary.

When discovery began (ie when we opened the dusty shed door), the throttle on passenger side was linked to the rear carb, even though the linkage to keep throttle plates closed meant nothing was happening in the first portion of throttle travel, and the choke was on the front carb. I assumed this was an error by my dad, so when we reassembled we built up the front carb on the passenger side as the primary.

The carbs were each capable of running a V8 bench motor at 300rpm when I got them back from the rebuilder.

Back on the car now, when hot, the Uni-Syn was pretty much maxed on the drivers rear primary with the dial max open, on the passenger front primary it came down a few graduations. Drivers secondary bumped along the bottom, but the passenger secondary was sometimes low and sometimes high. I'm not sure if it is stuck linkage or another problem inside the carb.

Now that they are in situ we are going to get the car back to the carb specialist on Wednesday and let him have a go at it.


For those that are curious: This car has an electronic ignition with an optical pickup inside the distributor, is bored .30 over with a mild cam upgrade, forged pistons, balanced internals, all new bearings, electric fuel pump with regulator, braided steel fuel lines, upgraded valve seats, tubular exhaust headers and the obvious manifold and quad carb upgrade. Compression checks and leakdown tests looked good in the records I found. It pulled nicely at full throttle on its maiden voyage this weekend.

[66vairguy]

Based on my recall, and Bob Helt's book, the secondaries did not have any vacuum ports. The pictures show a base with ports so it would be nice to figure out what model year the bases are. If I missed the discussion on what is in place for secondaries, my apologies.

I do use 62-3 year bases for secondaries for the idle mixture circuit like the 68-9 secondaries had. I replaced the notched throttle plates with solid from the original secondary bases. I found running a notched secondary throttle plate required closing ALL the carburetor throttle plates to get a low enough idle, so I put solid plates back in the 62-3 secondary bases. I plug the 62-3 base vacuum ports. Even with the rotated carburetors and moved choke vacuum pull off, it is not difficult to run the rubber vacuum hoses to the primary and I suggest doing that and install block off caps on the port tubes.

Note, recently we discussed the problem of installing the solid secondary throttle plate UPSIDE down and then you won't get a good seal when the throttle is closed.

Do your secondaries have the notched throttle plate or a solid throttle plate?

[6T5VAIR]

My secondaries are notched.

My carb specialist was surprised at this and thought perhaps four primary carbs had been adapted into the primary/secondary roles.

Can this be used without exchanging parts?