Varajet II carburettor

[Aaron IIA]

Does anybody have any experience adjusting a Varajet II carburettor, as fitted to Holden Blue and Black engines?

Aaron.

[stevep]

Does anybody have any experience adjusting a Varajet II carburettor, as fitted to Holden Blue and Black engines?

Aaron.

yes - they are great - (sarcasm)
does it have a flat spot just as you accelerate?

Steve

[Davehoos]

they all come with factory flatspot.

power valve stuck or the vac control for the secondary.

these also have adjustable main jets ect.VK black motor is the best for for 3.3
2850/173 use a late blue motor carb.

NZ VK often had webbers to replace the non pulution varijet.

[banjo]

Yep had one of then on my blue 202. Car runs great now , Has a 350 holley..could never get the verajet running properly..

[Aaron IIA]

I am running a red sump, blue block, black head and a home made copper exhaust manifold in a ski boat. I have just stripped, cleaned and re-assembled the Varajet carburettor, and so have lost the "set at the factory, do not adjust" settings. These carburettors have an idle speed screw, small mixture screw, and a large slug that is next to the solenoid. I am having difficulties adjusting these to get a smooth idle. Once this is done, I will then have to adjust the screws relating to how the secondary barrel opens. Has anybody successfully done this before?

Aaron.

[banjo]

I'm pretty sure i still have all the correct factory setting here in my books i'll have a look tomorrow for you & post em up..

Jason

[Davehoos]

lots of different carby as at the time different states had different ADR 27-A-B-C requirements.

NSW and VIC are different to other states

VK[black] was realy the only one to get to a stock settings as it was the end of the line.

under the carb float bowl is a main jet base mixture adjustment-behind a plug

concentrate on the primary barrel.idle is like most modern carby with a bypass for air to control speed.black motor also adjusts the timing to set idle.
idle jets use air bleeds.the air bleeds get bigger with engine size.

primary barrel main jet uses VARIJET POWER MAIN JET.the idea is that the fixed venturi mixture changes acording to engine load.at high rpm the air pressure draws fuel through a tube directly from the float bowl to allow for the fuel that cant get in to the venturi.these have a standard throttle pump with a slow timed spray.

secondary barrel works like a SU carby.its only for very high rpm and almost full throttle.
as the high speed air comes past the flap and opens up the secondary jet.

a vacume control holds the flap closed to draw in fuel to allow acelleration without pinking or a flat spot.as the vac falls from the engine throttle being open the linkage drop away and the air is allowed in.most of the time this vac diaphram is stuffed or the timer control has been removed so you get a big back fire.

the benifit of this is you get a carby that is always the right size for the job.holley 350 is over kill for a holden and most of the time you have to choke down the venturi to get fuel to mix properly.a dual stage carby is much better.as an comparison a 186S WW stomburge is about 250/280CFM and overkill.

Ive tried a few cars with single 1 3/4 SU and other than the odd refuse to start because its flooded of the slide wont lift-have been good.
the hassel with the su is no throttle pump-even though the varijet has a throttle pump its realy only used at slow speeds.when the varijet isnt adjusted or has air leaks it also drives like an SU.

[BigJon]

Does anybody have any experience adjusting a Varajet II carburettor, as fitted to Holden Blue and Black engines?

Aaron.

Adjust it into the bin. Well known as being a shocking heap of junk.

[Aaron IIA]

I ended up replacing it with a Weber from a XF Falcon. Best move I ever did.