Advice on buying Rochester Quadrajet

falloutboy

Veteran Member
Hi,
I need your knowledge again.
Is this Qjet correct for a 1979 Berlinetta with a 350cui engine? - thats what it supposedly came from.
Is this carb in good 'ready to drive' condition?
What additional costs do I have to consider, except the 80€ ~ 90$ buying cost? What do I have to do to make it run smooth and clean?

Numbers are:
17057202
0859AOL

so far, I came up with these links:
http://www.carburetion.com/CarbNumber.asp?Number=17057202
https://www.chevyhardcore.com/tech-stories/choose-your-quadrajet-number-identification-guide/

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Twisted_Metal

Administrator
Staff member
Lifetime Gold Member
Feb 26, 2004
31,907
Bloomington, MN
You don't need the electric solenoid and bracket on the front, driver's side if you don't have A/C.

Make sure the primary throttle shaft isn't sloppy and it rotates smoothly.
(It should only rotate, no wiggle front-to back or up/down. This is a problem which can cause a vacuum leak and sticking throttle.)

If it wiggles... the shaft bore may need to be drilled and sleeved.
 

jeff swisher

Veteran Member
Apr 26, 2018
1,962
Yukon Oklahoma
They are not difficult to rebuild at all if you know the little things and those are in most books on that carb.
If you do not know the little things like fuel well plugs seeping and warped tops from over tightening and other little things like clogged idle tubes then it could pose an issue making it run right if it has any issues now.

Looking at the front airhorn area where the long bolts go through to bolt it to the intake i see those holes are very worn.
That carb has been on and off many many times.
And look at the second to the last picture of the accelerator pump arm. It is all scratched up making me think that rod has been in and out of that arm many times.

I like those carbs but there aren't many carbs I do not like.
I did not like the SU carbs on a 260 Datsun I got for my son. I built an intake and stuck an early AFB on it.
Then my other son got a 1969 Mercedes with 2 Zenith carbs could not get kits for them. so mounted GM 2 jets onto it.
Carbs are fun once you figure out how they really work.
 

falloutboy

Veteran Member
Hi
Thanks for the evaluation. Indeed these bolt holes look pretty worn.
I can't really tell of the previous history of it. Supposedly it was on the camaro and was switch for a hood scoop and edelbrock carb, cause "i think it is cool".

So far I have a Holley 4150 double pumper (if I remember correctly ). I want to make the car more original but still keep the better changes the previous owner did.
So do the boltholes of an aftermarket edelbrock intake for a Holley even match up with the holes on the Qjet?
Obviously i'd need a spacer to match the spreadbore - till I can afford an intake for the Rochester.
Do the Adapters cause really that much trouble, vacuum signal, idle and running stumbles as I heard?

Can the choke be easily switched to electric?

Thanks for the help so far
 

jeff swisher

Veteran Member
Apr 26, 2018
1,962
Yukon Oklahoma
Do the Adapters cause really that much trouble, vacuum signal, idle and running stumbles as I heard?

Sometimes a spacer will do that and other times they will not.
I have ran spacers of many kinds on the RPM intake and iron Q jet intake and never noticed any ill issues with all kinds of carbs mounted on them.
But the RPM air gap is a different story. it is quite picky in cold weather and to get it to act right the off idle transition needs to be much richer.
My buddies LS 6.0 with a carburetor and Edelbrock intake does not like a spacer.. it will stumble especially when cold.
I tuned most of it out ..then he decided to do a cam swap and I ported his heads and added some PAC springs.
No more stumble and I could change the carb back to a leaner setting and the stumble was still there . Took off the 1" spacer and it removed all stumble and throttle response became much better.

It is a try and see deal many times.
I tested the Qjet on a Q jet intake and then stuck a much modified 4779 onto it with an adapter.. both ran excellent tuned for the application. but the Q jet on that spread bore intake made 10 HP more at the wheels.
This was a ported Iron Q jet intake.
Then I swapped an Edelbrock RPM intake onto the engine and retested both carbs.
This was a square bore intake. The Holley this time made 10 more HP at the wheels.

Fun testing things sometimes.
I tested a stock Marine Iron Q jet intake on that engine and it was 30 HP behind the RPM intake and the Ported automotive iron Quadrajet intake was only 10HP less than the RPM intake.
350" engine
 

budro6968

Veteran Member
Apr 2, 2016
4,183
Jax Florida
Hi,
I need your knowledge again.
Is this Qjet correct for a 1979 Berlinetta with a 350cui engine? - thats what it supposedly came from.
Is this carb in good 'ready to drive' condition?
What additional costs do I have to consider, except the 80€ ~ 90$ buying cost? What do I have to do to make it run smooth and clean?

Numbers are:
17057202
0859AOL

so far, I came up with these links:
http://www.carburetion.com/CarbNumber.asp?Number=17057202
https://www.chevyhardcore.com/tech-stories/choose-your-quadrajet-number-identification-guide/

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$_10.JPG
I would get a couple cans of gumout and a tooth brush. Clean it up and give a good shot down the vent tube and everywhere. Get the filter out and blast all inside the inlet. Make sure to open the throttle plates to get all that cleaned out. Turn it over to listen if the float is free. Let it drip dry or light compressed air blast to clear it out. Then install and see if it runs. These carbs are awesome and built to last. Might need a kit but worth a shot to try first.
 




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