delorto air bleed screws

[Over Steer]

Hey all

My carbs do not seem to be fitted with an air bleed screw. How am I supposed to balance the barrels on the same carb? I don't want to bend the throttle spindles if possible.

any ideas?

[alaric]

Here's some pics of my carbtune hooked up. It's what you labelled as the vacuum tapping - you need to be on the vacuum side of the butterfly valve.

[types26/36]

The later Delloto's (and Webers) were fitted with adjustable idle air bleed screws (although not in Elan/Europa production) so you just have to go with what you have got, never had any success bending throttle valves myself, in my experience its a bit of a compromise as to where you set one pair carb throttle valves compared too the other.
All you can do is get the best throttle valves position in relation the the other throttle valves.

[bcmc33]

From the Des Hammill & Miles Wilkins books it appears that the carbs you have were the early Dellortos fitted to address some European emision regulations (1970/1) that the Webers could not meet. To further improve the situation, Dellorto later produced the DHLA40 emmision controlled carb that Lotus used. This carb can be recognised by the recessed idle by-pass adjustment screws.
Wilkins notes that Dellorto carbs were used on Europa from late 1971 and on Sprints 1972. I guess there?s no way of knowing when the idle by-pass carb was introduced, but my Sprint produced late 1972 has them fitted.

[Over Steer]

Thanks for the feedback,
The carbs were originally on a 1973 Europa Special. There is only a very slight difference on one barrel. The other three are exactly the same. It's not worth risking damaging them by twisting the butterfly spindles.


Thanks for the information.