something to remember about a more agressive cam on the street. the
"overlap" at bottom end in the cam's timing causes som bottom end bog. in
the old days some cam manufacturers included a installation sheet with all
the specs on it including a reccomended idle range for that specific grind.
a "lumpy" cam sounds absolutly great at a low idle sitting at a light , but
is a dog with out bringing rpm's up into it's usefull range to pull out!
also a lumpy cam in it's lower rpm range can spit out fuel due to the poor
vaccume signal due to the overlap in the grind. this is where you begin to
throw out factory specs in the final tune of the end prodct and begin to
become your own home brew rocket scientist! grind of cam, advance curve
of timing, where the cam was dialed in with relationship to the crank,
choice of piston (both over bore and compression ratio) , and any
improvements in intake and exhaust combined with modifications to the
cylinder head makes the motor no longer properly responsive to the factory
specs! AND! depending upon what you chose, and how it works in
conjunction with the other mods you can actually spend a whole lotta money
and get a slower car with worse fuel economy in the end!
many arm chair hot rodders found this out buying stuff from catalogs based
upon the latest article in their favorite periodicals. when all the "cool"
items were bolted together some things just did not work right! the
biggets carb with the biggest header tube with the latest intake with the
reccomended cam from last month's article rarely ever worked! but they
sold a whole lot of cool stuff each month! wich is why going to swap meets
has become financially rewarding! (if ya know what yer shopping for!
*grin*)
chuck.
-----Original Message-----
From Chris King <cbking at alum.rpi.edu>
To: PilotRob@webtv.net <PilotRob@webtv.net>
Cc: spridgets@autox.team.net <spridgets@autox.team.net>
Date: Saturday, June 19, 2004 9:30 AM
Subject: Re: Carb tuning - "spitting"....sometimes referred to as
"standoff".
>Explains the bogging off the line if I don't rev the motor up a bit. The
>carbs are giving the proper fuel, but the engine just can't suck it in.
>
>My solution is to just blip the throttle before taking off, and it seems
>to work better.
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