Needles were my first route (way back when)
K&N's went to ABD than AAA...
then bought new carbs. Even went to #7's after
getting rid of the biased needle setup.
Have tried lighter, and heavier carb piston springs
...still does it.
Paul Tegler wizardz@toad.net http://www.teglerizer.com
-----Original Message-----
From John Kipping <johnkipping at inet.net.nz>
To: spitfire-enthusiast@egroups.com <spitfire-enthusiast@egroups.com>;
triumphs@autox.team.net <triumphs@autox.team.net>; spridgets@autox.team.net
<spridgets@autox.team.net>; spitfires@autox.team.net
<spitfires@autox.team.net>; mgs@autox.team.net <mgs@autox.team.net>
Date: Sunday, January 14, 2001 9:35 PM
Subject: Re: [spitfire-enthusiast] Pulsing and surging
>Paul,
>It sounds like a classic weak mixture to me, especially if pulling the
choke
>out stops the problem. From the late sixties there was a drive for more
>economy and better emmissions, and so cars where set to run leaner and
>leaner, so even with everythin on the car correct care has to be taken not
>to try and set it too lean, as then the car won't go properley and
>perversely more fuel is consumed. With the inevitable wear in particularly
>carb jets and needles fitting new standard items can result in more
problems
>as worn items wear rich, and with any deviation from a standard spec richer
>needles are required as the bolt on goodies inevitably flow better and so
>weaken the mixture. Apart from some standard bolt on combinations and carb
>specs where a correct replacement needle is well known a car will have to
>be set up on a rolling road, where the CO/CO2 balance can be analyzed under
>all conditions.
>John Kipping
>
>-----Original Message-----
>From: Ptegler <ptegler@gouldfo.com>
>To: triumphs@autox.team.net <triumphs@autox.team.net>;
>spridgets@autox.team.net <spridgets@autox.team.net>;
>spitfires@autox.team.net <spitfires@autox.team.net>; CARS
>spitfire-enthusiast egroups <spitfire-enthusiast@egroups.com>;
>mgs@autox.team.net <mgs@autox.team.net>
>Date: Monday, 15 January 2001 14:23
>Subject: [spitfire-enthusiast] Pulsing and surging
>
>
>>OK... here we go... this problem has not
>>changed through all the following repairs
>>and upgrades.
>>
>>Driving at steady constant speed I get a pulsing
>>or surging/dropout (what ever you want to call it)
>>You pull the choke out and it disappears with
>>it seeming like a bit more power coming in.
>>I've replaced fuel pumps, carbs, added fuel
>>pressure regulators, changes carb piston springs,
>>changed carb needles, air filter styles (stock -
>>free flow) exhaust system diameters, manifolds,
>>head gaskets. re-curved and /or rebiult distributors, changed
>>dist. models, points and electronic conversions.
>>
>>This problem appears on more than one marque
>>I own.
>>
>>Anyone have any wild ideas? past experiences?
>>Wonderments?
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