Group, some interesting subtleties have been brought out here. Tom
Bryant pointed out that a 'big' scoop can actually create a positive
pressure in the throttle bodies at high speed, pushing fuel back out of
the "A" type nozzles, a small amount but enough to burn the hoses if it
catches fire. This sounds like it could be serious, certainly is not
desirable. Could it be overcome by using the non-"A" type nozzles?
Perhaps someone would tell me why the nozzles need "idle air bleeds" on
'em anyhow, isn't that just another way for air to get into the engine
in the idling mode, in addition to the air passing the throttle plates?
Or is it to help vaporize the fuel leaving the nozzle by mixing it with
air in the nozzle?
John Beckett had previously told me he had trouble at Bonneville burning
rear pistons on his SBC because his air scoop was apparently biasing the
air flow to the rear Hilborn throttle bodies, overloading them, and
leaning out the mixture, which overheated the pistons. John then went
to carburetors, and went just as fast, and has a number of records to
his credit.
It begins to look like a 'good' tuner can get the mechanical fuel
injection to work fairly well, and get good performance, and the
'supergood' tuner who can really understand and manage the equipment, to
get optimum mixture in all the cylinders, gets the best performance.
Since I am a 'hardhead', and just always liked the 'looks' of the
Hilborn, I'm going to try hard to learn to be a 'good' tuner.
That reminds me of something one of the local judges on the Circuit
Court here told me years ago when I ran into him socially. "You know
Bill, most of the people that come into my Court are either nuts or
hardheads." Cheers from ArdunBill in the Great Dismal Swamp,
Chesapeake, VA.
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