Megaflow - Technical information
an ITG filter replaces an original equipment inlet system, the
fuel metering systems on an engine may need adjustment to compensate
for the change in air flow capacity. The following is a guide,
but the full engine range should be checked on a rolling road.
Weber, and similar types of carburettor, try the following:
Increase main jet 5-10 points
Reduce air corrector 10-15 points
Increase secondary main jet 5-10 points
Reduce secondary air corrector 10-15 points
Reduce primary air corrector 5-10 points
Increase main jets 5-10 points
reduce air corrector 5-10 points
For SU and other types using
a metering needle, it is necessary to reduce the diameter of
the needle near the narrower end. There is a large selection
of SU needles avaliable and we can help with recommendations
for trial. For Strombergs, Ford VV and GM Varajet carbs, information
and needle variants are more limited.
Fires, fuel 'standoff' and 'blowback'
The main causes of 'standoff' and 'blowback' are wild camshafts,
poor cam timing and poor ignition timing, but poor fuel metering
also has an effect. If a heavy 'standoff' of fuel is occourring
then some fuel will accumilate on the air filter. If a 'blowback'
occours, this fuel and fuel in the carburettor can be ignited.
Although the filter materials used are fire retardant, with
the inner layer of foam self-exinguishing, a fire fed by fuel
can seriously damage teh filter and a severe under-bonnet fire
may not be contained by the filter.