Tuning Dellorto Twin 40's
Discussion
I've just had the 45's set up on my Lotus 907 engine.
Stage one was a strip & clean, new gaskets, internal O rings, diaphragms and reassemble. The kits are available off eBay. £50 ish.
Stage two was a rolling road session with much twiddling of screws, new slow & main jets, and a diagnosis that a better fuel pump was needed.
New Facet pump & reg now fitted and the engine now runs like a dream. Several hundred pounds well spent.
Unfortunately this all happened in the Cambridge area so quite a few miles from you, but the reason for my reply is to suggest that a
quick balance session might well improve tick over but that's about where it stops. You will get out what you put in, in my case, 180 bhp.
Cheers,
Paul G
Stage one was a strip & clean, new gaskets, internal O rings, diaphragms and reassemble. The kits are available off eBay. £50 ish.
Stage two was a rolling road session with much twiddling of screws, new slow & main jets, and a diagnosis that a better fuel pump was needed.
New Facet pump & reg now fitted and the engine now runs like a dream. Several hundred pounds well spent.
Unfortunately this all happened in the Cambridge area so quite a few miles from you, but the reason for my reply is to suggest that a
quick balance session might well improve tick over but that's about where it stops. You will get out what you put in, in my case, 180 bhp.
Cheers,
Paul G
Balance on twin delortos or webers is easy providing you can stick an ear to a trumpet or can hear it with a stethoscope.
Raise the idle speed with the adjuster until you can hear the engine start to come on cam. This is characterised by the carb tone changing to a 'bark'. Providing you can hear this change ok, it is then a matter of turning the balance screw so that both carbs start to 'bark' at exactly the same point of adjustment on the idle speed.
You can buy airflow meters, but in all honesty, this method is both cheaper and better.
Raise the idle speed with the adjuster until you can hear the engine start to come on cam. This is characterised by the carb tone changing to a 'bark'. Providing you can hear this change ok, it is then a matter of turning the balance screw so that both carbs start to 'bark' at exactly the same point of adjustment on the idle speed.
You can buy airflow meters, but in all honesty, this method is both cheaper and better.
Back in the 80's I (and most of the other guys in my motor club) used to drive all the way up from West London to see the legend that was (still is) Pete Baldwin for getting twin DCOE's/DHLA's set up and tweeked on his RR......still never seen anyone do it so well, so quick and all by eye/ear.
He's still working his magic with a RR in Royston IIRC...
He's still working his magic with a RR in Royston IIRC...
aeropilot said:
Back in the 80's I (and most of the other guys in my motor club) used to drive all the way up from West London to see the legend that was (still is) Pete Baldwin for getting twin DCOE's/DHLA's set up and tweeked on his RR......still never seen anyone do it so well, so quick and all by eye/ear.
He's still working his magic with a RR in Royston IIRC...
Indeed he is. It was Peter I was referring to in my earlier post. /|\He's still working his magic with a RR in Royston IIRC...
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