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combination for club exhaust + K&Ns
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Section : Carburettors
Posted By : Robert Bell, 03-Jun-2005, 04:32pm
Hi folks,
Been reading through the archives and this seems to be a topic that comes up fairly frequently - albeit with cars with different specifications.
The problem I have with my Mk3, with its standard Mk3 1300 engine (unleaded cylinderhead) and standard Mk3 cams is that the engine has not run well -
practically since the day I bought it. Replacing the exhaust manifold with a club 4-2-1 and the air filters with K&N certainly haven't helped.
I am going to be checking the cam timing (thanks for everyone's recommendations for that), but the symptoms of poor running - failure to run well over
4000rpm, with pinking - could equally be due to poor needle and spring choice.
I rebuilt the carbs years ago - red springs, and AAT needles (IIRC - lost the paper work and notes I made due to house moves) - which may not be adequate.
I'll have to recheck the needles' specification (will the code be stamped on them?)
But what should the specification of the needles and springs be for this kind of specification? I have a suspicion that I should be using yellow springs
with AAQ needles...?
Help!?
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Posted By : David Rumens, 03-Jun-2005,
05:26pm
You can use either AAT or AAQ needles, AAQ needles are a tad richer. But in both cases you must use Yellow Springs.
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Posted By : Robert Bell, 03-Jun-2005,
08:35pm
Thanks for that confirmation David. Any idea how I confirm what the needle specification is?
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Posted By : Barry Huffer, 06-Jun-2005,
01:07pm
Its stamped on the needles but you need good eyesight or a magnifying glass!
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Posted By : Barry Huffer,
06-Jun-2005, 01:11pm
Sorry forgot to add if you go to Carruthers's Minty Lamb site he has a needle comparison bit of software that's almost as good as Winsu.
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Posted By : Robert Bell,
06-Jun-2005, 01:28pm
Thanks Barry *big smile*
Hmm - Minty Lamb? Okay, I am sure that there is a story there to be told! ROFL - do you have the URL handy?
At this risk of turning this thread into '20 questions' - can anyone recommend a particular supplier for these (sprrings/ needles) carb
components? Burlen Fuel systems perhaps?
Cheers
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Posted By : James Carruthers,
06-Jun-2005, 08:14pm
Almost?!
Club exhaust + K&Ns on HS4s with a 1500 engine - I found AAQs to be perfect.
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Posted By : Robert Bell,
08-Jun-2005, 12:51pm
Thanks James - will be buying a set of replacement needles and springs and will see how I get on *big smile*