[racing] triple SU carb needle selection

Racing
1

I’m building a 4.2 motor with straight through exhaust, isky
xm-2 cams, k&n pod filters and velocity stacks.
Does anyone have any suggestion for a good starting point for
the needles?
I’ve read elsewhere that a UE needle should do the job. does
anyone have any thoughts or input on the subject?–
jhkm
Atlanta, GA, United States
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2

In reply to a message from jhkm sent Mon 2 Jun 2014:

UVO no arguments trials etc needed, did all the hard work on
this…gosh is it really that long ago!
If I recall its ad Aston Martin needle.–
XJR5 006, & Jaguarsport Ltd for all things XJR15
London, United Kingdom
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3

In reply to a message from jhkm sent Mon 2 Jun 2014:

You need UO needles…–
The original message included these comments:

I’m building a 4.2 motor with straight through exhaust, isky
xm-2 cams, k&n pod filters and velocity stacks.
Does anyone have any suggestion for a good starting point for
the needles?
I’ve read elsewhere that a UE needle should do the job. does
anyone have any thoughts or input on the subject?

–
Keith.P. Series2 Roadster
exmouth, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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1 Like
4

In reply to a message from jhkm sent Mon 2 Jun 2014:

Yes no need UO needles.

mrosupply–
Sifat
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5

The needle you want will be UVO if you intend to use what you have got. The others will more than risk piston burn/ detonation at and around the mid point in acceleration.
Needles are cheap enough so test it with lambda sensors if unsure. Having said that you can often hear and feel the det if you have it wrong. Some folks just dont have the ‘feel’ for such things though.