RE: [Chrysler300] Carburetor rebuilder in SoCal
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RE: [Chrysler300] Carburetor rebuilder in SoCal

Thanks John, that’s great information. I need to work on mine more as I can’t get the idle down to where it should be. When I all the ram parts off to fix a bent pushrod I check the manifolds and such carefully. Couldn’t find any vacuum leaks either. My car had been converted to a 4-barrel somewhere before 1992, most likely in the early 80s. The owner’s daughter got the car out of the barn in 1992 and her husband put the original ram setup back on but he said he really didn’t know much about cars and just followed the manual. One thing he didn’t do was to setup the carb and kickdown linkage right. He sold it to a family friend before I got it and that owner didn’t drive it much. He said this was because he was afraid of damaging it but more likely that it didn’t run and shift well because of the linkage and carb adjustments.




From: Chrysler300@xxxxxxxxxxxxxxx <Chrysler300@xxxxxxxxxxxxxxx> On Behalf Of 'John Grady' jkg@xxxxxxxxxxxxxxxxx [Chrysler300]
Sent: Sunday, February 9, 2020 4:14 PM
To: nick@xxxxxxxx; 'Chrysler 300 List' <Chrysler300@xxxxxxxxxxxxxxx>
Subject: RE: [Chrysler300] Carburetor rebuilder in SoCal



Agree air flow between both sides at idle off choke has to be very close on
ram. However, vacuum inside manifold is the same on both sides on ram due
to balance tube, (unlike some British cars or bikes ) and if you carefully
count air valve opening in degrees / turns from zero on ram it (air)
should be close. ( "balancing" is mostly idle air flow, on otherwise
correct carbs..) ; the main difference on ram carbs is you do not open
throttle with an idle screw a bit for that air setting . That brass air
valve thing does it instead. That said, a Unisyn makes sense to check ..
But throttle valves MUST be closed all the way (linkage) I think the slight
slop in ram linkage is there to be sure they are both independently closed
against each one's stops . You can get a great balance reading , but it can
be partially air valve flow and partially throttle not closed. Especially
if others have been in there...

Vacuum tank leaks too.. My first F , way back, had a rust hole in vacuum
tank behind the headlights, defeated my tuning efforts for weeks. PB booster
too. And another F had a hole under carb plenum into exhaust heat space on
ram, because heat riser had been stuck "on" by rust , (the way it sits in
storage) melted a hole in aluminum floor of ram. Brings up leaving that heat
valve tied open, in mild climates. ..but ."not original" !!

Note how by 63 J they got rid of all that controlled heater / choke stuff,
and none made in 62 standard production ; There are good reasons for all
that... And most hi po race rams I have seen had been converted to water

One of the biggest inherent issues with rams is if the two chokes pull off
unevenly, one ahead of other, the rough idle grief starts..and they will DO
that, at warm up just how bad and for how long is the question, as well as
initially if on highway or in city, so making sure exhaust heat valve is
working perfectly , thermal spring has not been mangled, and then cut and
try choke adjustment until chokes pull off reasonably together from cold
start as best you can. Have to keep blipping throttle to see ? Less an issue
in warm climates.

Other sneaky problem is if idle mixture screws have a slight step worn into
them along cone from thousands of adjustments (the golden screwdriver was
here too) . Then it acts as on off valve suddenly during turning, instead of
smooth adjustment . Key clue..idle screws seemingly do nothing to change
anything ! Or suddenly stalls in 1/8 turn while turning . As mentioned
before, Edelbrock AFB needles fit, and are enough different shape they fix
this. Goes without saying use vacuum gauge, read for max.

Grey beard at work..why it is grey.


From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On
Behalf Of nick@xxxxxxxx [Chrysler300]
Sent: Sunday, February 09, 2020 5:07 PM
To: 'Chrysler 300 List'
Subject: RE: [Chrysler300] Carburetor rebuilder in SoCal

I had to sync my carburetors up on my 300F. You use a tool called a Uni-Syn.
You only need one as you do each carburetor separately. It measures the
airflow through the carburetor and you want them to match. They are
typically used on foreign cars with smaller carburetors so the tool does not
fit the Carter AFB carburetor air horn directly. What I found was that a
standard 1 pound cottage cheese or sour cream container fits the top of the
carburetor perfectly and then you cut a hole in the bottom of the container
for the Uni-Syn to sit on. I don't have a picture of the Uni-Syn on the
carb but this shows the container fitting over the carb. Also a handy thing
to have around if you're working under the hood with the air cleaners off to
keep stuff from getting in the carbs.

From: Chrysler300@xxxxxxxxxxxxxxx <Chrysler300@xxxxxxxxxxxxxxx> On Behalf Of
Andrew W QuietLion79@xxxxxxxxxxx [Chrysler300]
Sent: Sunday, February 9, 2020 1:40 PM
To: John Grady <jkg@xxxxxxxxxxxxxxxxx>; Tom Hergert tallzag@xxxxxxxxx
[Chrysler300] <Chrysler300-noreply@xxxxxxxxxxxxxxx>
Cc: spiers@xxxxxxxxxxxxxx; Chrysler 300 List <Chrysler300@xxxxxxxxxxxxxxx>;
Jim Pristelski <ajp002@xxxxxxxxx>
Subject: Re: [Chrysler300] Carburetor rebuilder in SoCal

Very good points, John. I just sent Scott at Harms Auto a message. He isn't
cheap, but since he is good with ram setups I think it is worth it. After
the base price of $200-250 per carb, you are paying for the experience.
Normally, I like to do everything myself and have been tempted to rebuild
them, as I have rebuilt a few carburetors myself, mostly successfully.
However, thinking about trying to balance them myself and futzing around
with them and never having the car run perfectly seems like a distinct
possibility, even though I have the 300J supplement manual. I think I will
request a step by step from Scott to set up and tune them (possibly rebuild
as well). If i do get that information, I can pass it along for future

Thanks for the (nearly instantaneous) help!



From: John Grady <jkg@xxxxxxxxxxxxxxxxx>
Sent: Sunday, February 9, 2020 9:39 AM
To: Tom Hergert tallzag@xxxxxxxxx [Chrysler300]
Cc: Andrew W <QuietLion79@xxxxxxxxxxx>; spiers@xxxxxxxxxxxxxx
<spiers@xxxxxxxxxxxxxx>; Chrysler 300 List <Chrysler300@xxxxxxxxxxxxxxx>;
Jim Pristelski <ajp002@xxxxxxxxx>
Subject: Re: [Chrysler300] Carburetor rebuilder in SoCal

This is a really important question I think . How do we know who is good, or
in my case , still good? Some of the older big names who routinely did a
great job (why name anybody...) now have young kids putting carbs together ,
often all wrong .... that business is about gone in a commercial sense .
And my former place had so many complaints -- I hear they now just sell
kits. Nothing is worse than a poor rebuild, factory things messed up .. in
my case , the Fit of throttle plates. Jamie has seen same thing, even
worse, parts from the two carbs all mixed up . Shows guy who did it was
I often wonder whether they they really DO need "rebuild "- except for
aesthetics ?
Thoroughly cleaning , with a Carter book, new inlet valves and float
settings , accell pump leather and gaskets , new idle needles done carefully
- might come out better than any 100 % disassembly . After all what IS a
rebuild? What you want is to fix what is wrong . J carb very special , few
around . Maybe this fellow is terrific , hope so , but anecdotes sort of are
not the test .

... I found a guy does almost all the race carbs around here ( NE)
,relatively good business at his home , a garage behind just for this ,
and half the usual prices , but have not used - so I am reticent to put up a
name . By the way fixed price up front , for any normal 4 bbl. - Not " we
will see " and then costs 900 for two carbs. What is normal ? Strikes me 150
-200 area seems right for time it takes .

But that "check local race guy " way seems a logical place to go .. ask
local successful engine builders - who does their carbs ? Start some kind of
club data base ? Real results . A club survey?
Bob Merritt ( once again!) working on a better rebuilding instruction set ,
on 300 site, to do it yourself. ( thank you Bob)
Except for repairing badly worn throttle shafts , fairly rare on our carbs,
you can do a good job if careful .
Some people within our club are in fact way better at carbs than " carb guy"
.. ; - the way their cars run show it ...
Just an observation on this issue-- no aspersions cast.
My success with external "rebuilds" hovers around 50% . Cost me a lot of
time later in some cases .. Generally able to fix it eventually, but that
goes full circle to do it right yourself ... then you know issues about
your own carbs too .
Good question ...

Sent from my iPhone not by choice

> On 9 Feb 2020, at 11:55 am, Tom Hergert tallzag@xxxxxxxxx [Chrysler300]
<Chrysler300-noreply@xxxxxxxxxxxxxxx> wrote:
> Best afb rebuilder is Scott Smith at Harms Auto in Spokane, Washington..
> Sent from my iPhone
>> On Feb 9, 2020, at 8:39 AM, Andrew W QuietLion79@xxxxxxxxxxx
> ] <Chrysler300-noreply@xxxxxxxxxxxxxxx> wrote:
>> =20
>> =EF=BB=BF
>> Hello, I was looking to have both my 3505s carbs for my 300J rebuilt and
> was wondering if there were any good rebuilders that someone wou

[Non-text portions of this message have been removed]


Posted by: <nick@xxxxxxxx>

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