What choke size did Moss supply. You probably want a 36, or 38 choke.
Smaller gives you better grunt off the line--limits upper rpm. Bigger the
reverse. The choke determines the velocity of the air column. I would then
try a fatter main jet. somewhere in the 150-160 range with an air corrector
at 180-190 range. Your idle jet is probably ok. At 3500 rpm you are out
of the idle circuit. The emulsion tube likewise although I always had good
luck with a F15. If you can find one, Haynes had a Weber manual (Haynes
#393) which is excellant. Has a good tuning section for the DCOE's.
Finally, there are sufficient variables in the jetting, emulsions, choke and
air correction to drive you nuts. However, if you get really good at it
(and invest a small fortune in spares) you can keep the engine at maximum hp
by altering the jetting to compensate for air density and temp/humidity.
That's what the racers did before black boxes and electronic fuel/ignition
stuff appeared. There was always one of the crew who could delve into the
mysteries of Weber and make them sing. Good luck.
----- Original Message -----
From: Matthew Wilder <mwilder@top.monad.net>
To: <fot@autox.team.net>
Sent: Sunday, June 04, 2000 6:02 PM
Subject: Need Weber tuning suggestions
> Hello,
> I ditched my SU's in favor of a set of 40 DCOE's from Moss. I got them
> Friday took them out of the box and put them on the car and ran it today
> in an auto-x. They seemed to work great up to about 3500 rpm then it
> just ran out of go and wouldn't make it over 5000 rpm. I'm running
> about 11.5 compresion with some head mods and a "D" cam. The settings
> Moss suplied are:
> Air corrector jet 180
> Emulsion tube F 11
> Main Jet 130
> Idling Jet 45 F9
> Pump Jet 40
> I also didn't do anything with the float level yet.
>
> Any suggestions on what setting to use to wake this thing up?
>
> Matt W.
> '67 TR4a E-prepared Solo 2/auto-x
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