Re: Dellorto SSI Choke
Posted: Thu Aug 18, 2011 9:04 pm
I'd like to use an SSI, and get it to idle- reading through the SSI manual in the tech section of this site I found this:
"Idle Device: in these carburetors, two are the idle different systems:
with Interchangeable jet and air adjusting screw fitted on carburetors where the engine needs a high operation sensibility at low speed;
with variable pilot jet by screw and air fixed, fitted on carburetors for racing engines, where these, according to their use, do not require a meticulous idle."
and this:
"IDLE ADJUSTMENT
In the first idle system,, where is subsisting the replacing jet and the air adjusting screw, you must operate on this air screw in order to obtain a correct carburation, bearing in mind that by tightening it the mixture strength is enriching, while by unscrewing it the mixture strength is weakening.
In the second system, where is subsisting the variable screwed pilot jet and the fixed air, the wished engine running will be obtained by operating only on the screw which adjusts the fuel passage; the mixture strength will weaken by tightening this screw and will enrich by unscrewing it.
This second idle system, although it is not exact and sensitive like the first one (suitable to particular uses and engines as told in the general features) allows a better and quicker mixture strength change; it favours therefore easy corrections of carburation also in the passage runnings and necessary easy enrichments in case of alcohol feed."
Maybe I'm the last to know about this, but there appears to be 2 styles of SSI carbs, possibly the 'SSI-A' and the 'SSI-B', that have much different idle circuits- one designed for racing and another designed to behave better for street use.
I can't find a good exploded diagram to show the different parts involved, but the main castings are probably the same- has anyone ever converted the 'race' style idle or pilot circuit into the 'street' style'?
I'll keep looking for good diagrams.
Rick
"Idle Device: in these carburetors, two are the idle different systems:
with Interchangeable jet and air adjusting screw fitted on carburetors where the engine needs a high operation sensibility at low speed;
with variable pilot jet by screw and air fixed, fitted on carburetors for racing engines, where these, according to their use, do not require a meticulous idle."
and this:
"IDLE ADJUSTMENT
In the first idle system,, where is subsisting the replacing jet and the air adjusting screw, you must operate on this air screw in order to obtain a correct carburation, bearing in mind that by tightening it the mixture strength is enriching, while by unscrewing it the mixture strength is weakening.
In the second system, where is subsisting the variable screwed pilot jet and the fixed air, the wished engine running will be obtained by operating only on the screw which adjusts the fuel passage; the mixture strength will weaken by tightening this screw and will enrich by unscrewing it.
This second idle system, although it is not exact and sensitive like the first one (suitable to particular uses and engines as told in the general features) allows a better and quicker mixture strength change; it favours therefore easy corrections of carburation also in the passage runnings and necessary easy enrichments in case of alcohol feed."
Maybe I'm the last to know about this, but there appears to be 2 styles of SSI carbs, possibly the 'SSI-A' and the 'SSI-B', that have much different idle circuits- one designed for racing and another designed to behave better for street use.
I can't find a good exploded diagram to show the different parts involved, but the main castings are probably the same- has anyone ever converted the 'race' style idle or pilot circuit into the 'street' style'?
I'll keep looking for good diagrams.
Rick