Lotus Elan

Stromberg needles & jets

PostPost by: Tonyw » Mon Oct 08, 2012 2:08 pm

I have spent a good deal of time in the archives looking for a solution to my little ptoblem. I have a SE DHC with Strombergs, I had adjustable jets on a pair of NOS that I was using but since I have changed the engine mounts to the correct type for a Stromberg the adjustable jets touch the top of the pedal box area on hard acceleration.

Fitting a used pair of Strombergs I have found the fuel mixture to be to rich running at around 11-1 to 12-1 at idle and not much leaner on partial throttle so I obviously need to replace the needles but I am unsure which would be best to use, looking through the archives it seems that B1G, B1y and B2AR are used but there seems to be no reason for one over an other. I have removed the needles and set them as per the manual (these are non adjustable) the car runs really well and has plently od power it just runs to rich.

I am thinking I need to replace the needle and was hoping to try and get some of your collective wisdom as to which ones I should be using, furter should I also replace the jets or move them a little higher in the body to try a lean off the mixture. Needless to say that the float levels have been set, both carbs cleaned out and new gaskets float valves and diaphragms have been fitted.

Looking forward to hearing what others think?

Tonyw
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PostPost by: 69S4 » Mon Oct 08, 2012 3:39 pm

Hi Tony. If you haven't replaced the jets that's worth doing. They do wear and the wear patterns were visible in my old ones. Measure their existing position before you knock them out so at least you've got a reference point. When I did mine I couldn't get much info on what the exact height should be but I've at least got adjustable needles which will take up a bit of positioning slack. There are differences between the profiles of the three needles you mention and they are the usual suspects. I spent ages pouring over the differences in a whole range of needles (same problem, running rich) and then went with what was in there already (B1Y). New needles and jets made a big difference.
Stuart Holding
Thame UK / Alpe D'Huez France
69 S4 FHC
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PostPost by: oldelanman » Mon Oct 08, 2012 4:08 pm

Hi Tony,
If you've searched already you will probably have come across the spreadsheet where you can compare the various needles but just in case you haven't here it is again......
stromberg_needles spreadsheet.xls
(59.5 KiB) Downloaded 647 times
Roger
S4 DHC
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PostPost by: Tonyw » Tue Oct 09, 2012 2:25 pm

Guy's,

Thanks for the reply's, I will order a couple of new B1G's and jets and then see how I go with that. I did see the spreadsheet and have saved a copy for future reference.

Regards,

Tonyw
Second childhood? no just an extension of my first.
Tonyw
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Posts: 404
Joined: 23 Sep 2006
Location: Perth Australia

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