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GY versus V3 needles in SU carbs

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irish

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The PO of my 61 Sprite had GY needles in the SU (H2) carbs which is the recommended needle for the carb on a 1098 engine; only confusion (in my newbie sprite brain) is that I am certain the car has a 948 in it and the recommended needle for that engine is the V3.

The V3's are actually shorter in length. I know that the SU carbs work on either engine size but why are the V3 needles recommended for the 948 and the GY needles for the 1098? /ubbthreads/images/graemlins/computer.gif
 
Hi Irish,
The GY needle is about 8-10% leaner than the V3 in the mid range & 30 to 40% at the wide open position. There could be several reasons for the factory originally specing leaner needles on the 1098 than on the 948. There also could be various reasons for the PO switching to leaner needles on the 948.

If you think that your engine may be running a bit lean, switch to the richer V3 needles & see how it works.
D
 
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