Hey Guys,

Is there anyone out there who can sell me some needles for me flat top su's apparently they are the same as round tops.

I need an assortment because I dont know what I need. more or less fuel at top rpms.

Cheers

It's going to be hard to tune if you don't know if you are running rich or lean at the present. How will you know when it's just right if you don't have the right testing equipment available?

Flat top SU's? Are they actually SU carbs, or Hitachi's which are different & do not readily take SU needles?
If they are actually SU carbs, then there should be a wide selection of needles available, but not so good for the Hitachi carbs.

Hey,

I've just been through this exercise, with my L20b and flat top SU's.

This website has a lot of info and a excel file you can download to compare different jets.

Hitachi SU website

How do you know it's lean high in the rev range?
Alls SU's have stamped numbers on the needles, check what your needle is then find a comparison needle with the excel as an example I had M66 needles but I inceased the motor from 1800cc to 2000cc so I needed a needle richer across the whole rev range, so I orderd a pair of SU needle very simular to the M87 nissan needle and they work a treat. cost about $30 for a pair of needles.

As a first test try sliding the needles up all the way in the mounts this will increase the fuel across the rev range, but it should help you know if you need different needles or not.


Hitachi SUs and British SUs about the only part that is the same is the needles.

cheers

Jeezus Dodgeman , why is it that every time someone calls the Hitachi's, SU's you pipe up and say they are not. You are wrong, they are made under licence to Skinner Union (SU ) and have British patent numbers on them. Stop being so god damn anal.....

Quote:

Lots of Hitachi needles available from the good fellows at www.ztherapy.com

I know that the needles do fit. I changed some over from some genuine su's.

It didnt change. It still dies at 3-4k rpm.
The growl out of the intake is really loud. Its louder than the exhaust. I cant tell weather it is leaning or feeding too much fuel. Dad seems to think its over fueling because the needles are out of a 1600.

Wind the needles in till they bottom and then wind them out (clockwise) ten flats of the nut. That is a good starting pint to get the correct needle position. If you have just fitted them make sure there are no vacuum leaks as this willl cause the same symptoms.

Quote:

edit::

for the sake of braindeads like old demo here, if someone here says a flat top su, everyone but DEMO knows we are talking about a hitachi side draught, just like everyone calls an 'airbox' an 'airbox', not a 'air filter assembly housing' etc etc etc.
if you need to vent mate, take it to the bedroom with an old sock and a Picture mag.

im with dogerman

pepper has no idea

maybee pepper should ask her boyfriend

i got everything for hitatchi,su,wenbber,holley,bg,

but unless pep gives head
she aint getting nothing

this issnt going to turn in to another bitch session is it