HIF 44 needles

[landrovernuts]

Can anyone suggest a good needle to put in HIF 44 carbs on a Boxer set up. The engine is a 4.2 with stage 3 heads, 9.75 comp. ratio and 3.9 EFI camshaft. Currently on 2 SU's fitted with BAF needles and runs spot on.

[kiwicar]

I can't answer your question directly but you also need to consider the carb piston springs aswell, for the 3.5 engine I had to install the lightest spring I could get when I used this set up. I think your only way with this combination will be trial and error with the help of a wideband lambder sensor. There is a post on here I did about six weeks ago on what you are aiming at with the SU to get the piston lift right (I think the question was about a 4.6 on twin SUs) http://www.v-8.org.uk/forum/viewtopic.php?t=1875 this is it . You will probably be able to start it on the standard 3.5 springs and needles and set the idel mixture set on the main jet height and the piston lifting spring. You will need to get it running at idel on what you have, get the piston lift set up then swap needles and use the lambda sensor to choose a needle. Keep working with it as it takes a while to get running right and you may (probably) will find the set up on the carb with the two cylinders firing right after each other will need a different set up of spring, needle and damper oil to get it at its best (initial sel up with the damper rods undone then fine tume it on damper oil).
have fun
Mike

[landrovernuts]

Thanks for the reply - will have a go when the Land Rover Widow lets me back in the garage!