possibly two or more problems but most obvious to me....
1) the oil in your dashpots may be a bit thick when cold,
this limits how quickly the air volume can increase as you
open the throttle. Putting your foot into it when cold effectively
adds high vacuum, pulling gas, but the air volume doesn't match.
2) the cold manifolds may not be atomizing fuel properly
as the engine warms up, the gas air mixture is incorrect (again air/gas ratio)
the gas will puddle rather than atomize, and not be burning completely
as it is not readily pulled into the combustion chambers is a readily
burnable state.
my $.02 YMMV
Paul Tegler
1973 BGT
North of Annapolis, South of Baltimore
email: wizardz@toad.net
-----Original Message-----
From: DWARE@uk.ibm.com <DWARE@uk.ibm.com>
To: Spitfires@autox.team.net <Spitfires@autox.team.net>
Date: Friday, May 14, 1999 6:05 AM
Subject: Lack of Power
Hi,
I'm sorry to admit it but I'm a lurker. I've been sitting watching the list
for a while,
taking in all the excellent information that is generously given. Well, I'm
now
calling on your help, I have a problem.
My Spit starts fine from cold in the mornings, just a little choke needed
but for
the first couple of miles of running I have the problem that whenever I put
my
foot down to accelerate from idling (e.g. when pulling out of junctions) I
get
nothing and can only slowly move off, then in a couple of seconds the
_power_
kicks in and everything is okay again. Once the car has warmed up a little
everything seems fine. This can obviously be quite worrying when you are
pulling out across a busy road with cars coming at you from all directions.
My Spit is a 1977 1500, UK spec with twin SU carbs. It has the Waxstat
(sp?)
jets, I've heard that these can cause problems, could they be the culprits?
I've adjusted the mixture and balancing and I believe those to be okay.
Any advice will be gratefully received,
David Ware
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