Choking a carbed V8
Discussion
I'm building (very slowly) a V8 powered car, with a Rover 3.2L that has a "boxer" inlet manifold with four HIF-style SU carbs on it. See below I'm putting in the control cables and all the throttles move off one cable, via a linkage, of course. But the choke cable and linkage only moves the rear two carbs' choke control. There isn't a linkage to the front two.
This won't be a 'nipping down to the shops' car, it'll be used for track days, so warmed-up before use, but will it cold start on just two choked carbs?
This won't be a 'nipping down to the shops' car, it'll be used for track days, so warmed-up before use, but will it cold start on just two choked carbs?
A friend with a supercharged 5.2 on SUs noticed that it was running a bit flat at the end of some of the longer straights. Turned out that it was basically running on acceleration enrichment the whole time. The performance was so manic that he never held WOT long enough to get into a steady state.
technically SU's do not have acceleration enrichment.
It is achieved by the restriction of movement upwards of the dashpot...which in turn increases airspeed over the bridge where fuel is lifted causing it to draw more fuel, then as the dashpot rises to a more balanced position for the actual airflow....it's back to a more steady state fueling.
But there is nothing physically squirting more fuel in as would be in other carburettors.
It is achieved by the restriction of movement upwards of the dashpot...which in turn increases airspeed over the bridge where fuel is lifted causing it to draw more fuel, then as the dashpot rises to a more balanced position for the actual airflow....it's back to a more steady state fueling.
But there is nothing physically squirting more fuel in as would be in other carburettors.
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