Lotus Elan

Dellorto running very rich

PostPost by: crypto » Sat Sep 29, 2018 4:41 pm

My question is, who is using Dellortos on an S4/Sprint with the jets etc. exactly according Workshop manual and how is the engine running ?

I had my carburettors apart for cleaning and to put new gaskets in because the engine never really run well. This was when I noticed they had wrong jets from the PO. So I ordered the correct sizes with new valves and gaskets in the hope it would cure the problem. Unfortunately it is as bad as before. I adjusted the float level, measured fuel pressure, synchronised carbs with an air flow meter, set ignition timing, dwell angle, idle etc.
I had a wide band lambda sensor inserted to tune idle and to measure lambda during driving but it is always too rich and the black plugs confirm that. I'm running 95 octane.

The really good drivers have the bugs on the side windows (cit. Walter R?hrl)
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PostPost by: richardcox_lotus » Sat Sep 29, 2018 7:33 pm

In which case are you sure you?re getting a decent spark ??

And at the right time ??

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PostPost by: webbslinger » Sun Sep 30, 2018 12:33 am

I have limited experience, but I don't believe there are a lot of twin cams around that you could jet to spec and get running just right without some experimenting. It sounds like you are close though and the A/F guage will be a big help getting it right.
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