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BJ8 carb sync using a Uni-Syn, can you actually use it?

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Randy Forbes said:
If you can get your hands on a chainsaw, why would you use a stone axe to cut your firewood?
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And if the chainsaw wont start what do you do ...........go back to basics .
The SU carburetors are very simple , as long as the jet is centered correctly and the throttle shafts are not worn and leaky then everything else can be set by ear and eye no fancy gauges or electronic gadgets needed .
 
Randy Forbes said:
Andrea's pictures:Wideband O2 sensors mounted in downpipes:
IMGP1535.JPG
I wish there was a way that the two of us could get together and compare our cars side-by-side__YOURS WOULD "WIN" BY MILES (is win by a kilometer even a slang term in Europe...?)__but I'm sure we could stare at the most interesting and minute details for hours.
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Hi RandyI agree with you, and on my dream is a swimming in your Florida-pool (without the crocodile)My luckily is to have as neighborugh a shill race mechanic just in front of my door, VITO have a great part in my AH restorationCheers
 
jjs64bj8, I have HD8 carbs on my BJ7. HD8 carbs are not adjusted like any other SU Carb. You start off with making sure that the throttle plates are closed. If you are installing the carbs on the engine that is easy to do because you can ensure the throttles are both closed before you snug up the interconnecting link between the two carbs. These carburettors run at idle with the throttle plates closed. The slow run screw is an idle setting screw. You do not move the throttle plates to adjust the idle speed. This slow run screw passes the full mixture of air and fuel around the throttle plates to achieve idle. (this is just like an American carburettor which has idle mixture screws ). As you move the slow run screw out the idle will increase it is just passing air/fuel around the throttle plate. The throttle plate stays closed. There is no balancing as in the other SU carb set ups. The throttle plates stay closed so the air going thru can't change. The slow run screws should end up at very near the same number of turns out from bottom when you achieve the idle speed you want. If they are way different, the carb is dirty or your jet needs adjusted. You set the jet for rich or lean the same as other SUs. One poster mentioned about two different idle speed screws... The one labled "fast idle adjusting screw" is for setting the speed of idle when the choke is pulled out. If look closely you will see that when the choke lever is pulled, it will lift on that screw which will increase idle. You don't want that screw touching anything when making basic carb adjustments. Also be careful when setting the choke idle speed because trying too get too much idle speed with that screw can affect your basic settings. I don't use the fast idle speed screw much. My BJ7 with HD8 carbs and a BJ8 cam idles at 400 rpms. Good Luck.
 
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