[Cliff R]

The only manual choke Q-jets I'm aware of were used on some Holden V-8's up thru the mid 1970's......

[Shiney005]

The GMH built Holden Monaro's that were factory fitted with Chev's between 1968 and 1975 used the 4MV (Divorced choke) while all Holden V8's (308 CI) used the 4MC. All Quaddies fitted to Holden's had the number 8 for the sixth digit of the part number.
The 1974 L34 Torana was fitted with a manual choke from factory. This was a limited run of 263 cars to homologate the model for racing. I don't know if the carbys arrived in Australia already modified by GM or if the work was done here by Holden.

[Half-Inch Stud]

Thought i'd be ahead of thetech, and removed the Q-JET Choke with big cammed 472s. Worked fine until i went low compression. No cold starting so went with the 1050 for good cold-start.

Then realized cold-start is fine with the Choked Q-JET.

[zippy]

I have a manual conversion on my Q-jet and I love it with my 455. Here in Canada, the temps vary so much that one is constantly adjusting the electric choke. I pump pedal twice, pull choke on, Fire her up and feather choke down to mid idle after bit, depending on the present outside temps. Allows me to keep RPM up, or drop to the choppy idle sooner.

And it's not that I 'can't" set elec choke up. Its that I Prefer the manual choke in my TA. Also kind of a theft deterrent. Aint no one getting her started when she cold, without knowing where the choke cable is and how to use it.

[mgarblik]

Originally Posted by Shiney005

The GMH built Holden Monaro's that were factory fitted with Chev's between 1968 and 1975 used the 4MV (Divorced choke) while all Holden V8's (308 CI) used the 4MC. All Quaddies fitted to Holden's had the number 8 for the sixth digit of the part number.
The 1974 L34 Torana was fitted with a manual choke from factory. This was a limited run of 263 cars to homologate the model for racing. I don't know if the carbys arrived in Australia already modified by GM or if the work was done here by Holden.

Attachment 663100

Attachment 663101

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Attachment 663103

Boy, that's another one of those never say never deals! Learn something new every day.

[TXSTARFIRE]

Does that L34 have dual ignition coils? Looks like distributor cap has two coil terminals.

[Bruce Meyer]

Originally Posted by Schurkey

The bigger question is why a person would WANT a manual choke. If the individual parts work properly and are adjusted properly, an automatic choke works well, and seamlessly.

Some people block off their crossovers to keep the manifold cooler. Cooler manifold makes more power. With blocked crossovers the thermal spring type
choke wont work at all. Im glad I live in Phoenix az. I block the crossovers and dont need no stinking choke.

[unruhjonny]

Originally Posted by zippy

I have a manual conversion on my Q-jet and I love it with my 455. Here in Canada, the temps vary so much that one is constantly adjusting the electric choke. ...

When properly set up, you should not need to re-adjust, unless your engine is barely streetable.

Every Quadrajet I have set up with correct ect parts has worked flawlessly year round.
(Also notice that my avatar is my car post-paint, in the snow)

[Sirrotica]

Originally Posted by unruhjonny

When properly set up, you should not need to re-adjust, unless your engine is barely streetable.

Every Quadrajet I have set up with correct ect parts has worked flawlessly year round.
(Also notice that my avatar is my car post-paint, in the snow)

I have to agree with Jonny. There is absolutely no need for a Q Jet with a manual choke IMO. Likely why GM never offered any such option.

After reading Doug Roe's book on modifying Rochester carbs, attending a GM technical school on Q Jets, plus running them on my race cars, as well as street cars, they're the closest thing to driving a computer controlled fuel injected car when adjusted properly, no matter what the ambient air temp is.

Every circle track car I've been involved with the exception of one car, has had Rochester carbs on them. They need little to no adjustments on them once the carb is set up properly. Yes I've tried holley carbs, but have never had any measurable increase in performance over the Rochesters, and a lot more maintenance to keep them in top form than a Rochester based carb.

There is also a lot less possibility for them to leak fuel onto the engine as there are no gaskets keeping fuel in the bowls such as holleys have, lots less possible leak points, and fire potential.

My , and experiences, YMMV.