[DeTomaso] Carb jetting, general guidelines wanted

[Göran Malmberg]

Hi Tomas.
The problem with Holley carbs is the low speed system. The idle
system works quite high up the rpm register. The main jet is mostley
for the main system, but as the idle system is fed thrught the same jet
it does influence the idle system. The idle screw is does only affect
the idle hole in the trottle bore while the low speed hole that is located
higher up is not affected by the idle screw, althrought it is the same 
system.
This means that the low speed sytem has no own adjustment, other than
the main jet. But if the mainjet is perfect to the to the main system we
are  having a problem calibrating low speed then.
One way to get around this is to install low speed airbleed jets. This will
only affect the low speed system.
Back to the question. I don know what the carb did look like, but iv the
airhorn had a sudden end with sharp corners, air enty is gratly affected.
and since the low speed is on very sensitive area of the Holey function
I should leave the door open for such effect as you describe. Making a
1000 cfm carb out of a normal dubble pumper is just skipping the choke
airhorn and rounding of the air entry, from the factory.
Goran