run it with the whatever needles are in them first (ID is stamped on the needle's base) to get some sort of idea where you stand. Then depending on wether its lean up top or whatever you can choose different needles.

Any decent carb parts shop (or MG/Rover specialist) will have a listing of needles and their calibrations which will be able to help identify a suitable needle. SU needles are metered at certain increments for the first 1.5" from the shoulder, any length past that is just waste material. So for example, if it is lean up top, you just need to look for a needle with similar calibration for the first 1/3 and gradually thinner (richer) for the rest.

How far you had to wind the jet down (to make it richer) to correct it's mixtures at high rev/load (that would obviously make it too rich at low speed, but this is just for sorting purposes) will give you an idea how much richer the new needles need to be, because each full turn of the jet moves it down a fixed amount equal to the pitch of the thread (which I can't remember now - 1.5mm?) and that will tell you where you're at on the current needle's chart.

don't know if that made sense, it's a bit hard to explain just in words, but its alot easier than it probably sounds

feral, wouldnt he be better off getting needles suited more so to the new modifications to his motor as im sure with all the mods it has recieved it would benefit from diffrent fuel delivery ect ect???

If they are from an A14GX they should be fine as they are for your engine.

any idea's or recommended needles for my motor ?

thanks

same kit just order the one for the 180b

deos anyone know, the part number for the twin 38 Hitachi SU's? as i am looking for a rebuild kit for them...they have come off a A14gx motor, but i think they orginated off a 180Bsss.

does anyone have a good knowledge of what needles to run in su's?. as i have a A14 bored out, with mild cam, stock pistons and a ported A12gx head.. anybody recommend a needle type?

how much were the redline/lynx manifolds.
and the GX manifolds from an a-14 or 15

you'll want a GX manifold, as these had the twin 38 Hitachi SU's standard. Lynx or Redline make one as well, but I think it's only round port. I modifyed one of those a few years ago to suit the oval port A14 head when I upgraded from the A12. Just a simple cut and shut onto the standard A14 manifold just before the split into the separate runners for each port. A clean up with the angle grinder after having it TIGed and your away.

http://datsun1200.com/modules/myalbum/photo.php?lid=619

ps - the Sports2000 had twin sidedraught Solex (Weber style) carbs.

thanks for that i'll give it a go and see what i can get

also if it's on an a15 will it bolt on an a14 head

they came out on: Bluebird 411 SS and SSS, 240Z/260Z, B110GX, B210GX, PE10, 180B SSS, P510 SSS, and 311 roadsters. Available in "dome-top" through 1972 and then "flat-top" versions in 1973 and up. Most use the 38, but there are 46s on the 2000cc Roadster.

you need a mainfold like this: http://datsun1200.com/modules/myalbum/photo.php?lid=1132