These air flow synch tools or "Carb Synch" (as I remember the brand
name was on my old one), are an ABSOLUTE necessity for multi carb'ed
engines using either SU's, Stromberg, Weber DCOE's (Side draft), Weber
Down draft (cant remember their designation right off hand), and the
Zenith Down Drafts. This IS the only way to make sure that you have
equal vacuum between each pair of cylinders, or between each cylinder in
the case of the DCOE's.
When I had my old Alpine, I had a friend in the junk yard business, who
let me try all of the different combinations on my 1592. I started with
the stock 2bbl (whistling) Solex, then to the side draft Strombergs, and
then the down draft Zenith's. The Zenith's produced the most power, and
the smoothest response. The Stromberg's gave the best fuel economy.
The Solex, gave ....well, the best Whistling noise (Dammed annoying).
These changes would not have been feasible with the Carb Synch. When I
moved into motorcycles, everyone was using Mercury filled carb stix to
check vacuum per carb (X4). They were semi dangerous to use because of
the potential for Mercury contamination. I used this old beat up carb
synch that no one had seen before. I had to make a small adapter plate
but adjust easily to this, and worked perfectly. I have used it on
multi cylinder out boards. Two strokes are very picky on mixture, and
one cylinder that is too lean under a load will most likely score the
walls or worst case, melt the top of the piston which = Total rebuild.
Buy one, live with it for a while, then Marry it !! It will never let
you down....
Rich
25 year old Carb Synch
>----------
>From: Steve Sage[SMTP:rootes(at)ix.netcom.com]
>Sent: Thursday, November 21, 1996 9:02 PM
>To: Alpines(at)autox.team.net
>Subject: Re: stromberg blues
>
>Doerrer(at)aol.com wrote:
>>
>> replaced O ring in both strombergs from rebuild kit purchased from sunbeam
>> specialties. when I pulled out old large o-ring, i noticed fiberglass
>>string
>> underneath presumably to enlarge o-ring. decided not to remove ring. Has
>> anybody needed to do this? Also, about how many turns of the jet
>>adjustment
>> screw from flush position are everybody's set? I think mine need more than
>> three. Feedback?
>
>I'm not an expert at much about our cars but on Strombergs I think I can
>offer a couple of pointers from lots of aggravation and learning.
>
>I'm not sure what you're refering to about the fiberglass string.
>
>Re: the turns of the jets, you will find every Stromberg, after all these
>years of use, will require slightly different adjustments as various
>parts are worn, unevenly, past their original specs.
>
>You will NEED to get a carb airflow reading tool, which should be
>available for $10 or $20 from most speed or performance shops. You fit
>this over the carb opening, with air cleaners off, and read the airflow
>at both idle and higher RPMs. You will probably find, as I have, that
>with both needles adjusted the same, the airflow will differ through each
>carb. This drove me even nutsier than I normally am as I couldn't get the
>airflow the same. Two carb shops couldn't tell me what the problem was.
>Finally, I found out on my own that the butterfly flaps had worn
>unevenly, one having a slight gap letting airflow through even when
>"closed". Since I couldn't get new butterflys, I adjusted the one that
>was not worn to a slightly open position (you have to do this with the
>carbs off the car). This resulted in a slightly more open position than
>"normal" for both butterflys at idle but gave equal air flow. Then it's
>just a matter of adjusting the jet screws, using the carb air flow tool,
>and your ears (for listening, not sticking on the carbs!) until you get
>smooth idle and acceleration curves. You'll probably have to "average"
>your adjustments...in other words, you may have to sacrifice a perfect
>idle somewhat to get even air flow on acceleration and high end cruising.
>
>I'll also tell you from experience that the Strombergs, set up properly,
> give much better acceleration and throttle response than the
>"replacement" Holly-Webber single carb some Sunbeamers recommend a change
>over to. True, you do have to adjust the Strombergs fairly regularly, but
>once you get the hang of it, this is an easy 20 or 30 minute task once a
>month or two and well worth the results.
>
>Hope the above makes sense & is of some use to you.
>
>Good luck.
>
>
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