Tue, 4 Jan From: "DrMayf"
"Mayf...Wow, when did this thread start? What kicked it off?"
Believe it or not, Mayf, I started it by asking about adding a SOHC and
other stuff to a Production (PRO) engine. Someone mentioned a 4 valve hemi,
Dave kicked in saying hemi efficiency was a mystic, and then somehow John
submitted some basic physics. It has now morphed to the current topic.
Don't you just love it! You never know where a thread will take you. . .
this list is better than a thrill ride1
"Mayf.. .So prolly the aceleration curve is a lot diferent that like a
falling object. LIkely to be slow acceleration then ramping up to max accel
just to keep from over powering the track."
The 1st 60 ft of all NRHA tracks (except Brainard which is 1320ft) is
concrete. It is groomed, occasionally heated after a spill, and laid down
with rubber and rosin. The greatest friction(adhesion) occurs there. The
vehicle is at rest so there is not aero at all. At top end there is aero
drag, INCLUDING incredible drag from the WING! Power must not only
accelerate mass but it must overpower increasing drag. Power production is
essentially constant so acceleration has to be less at top end. The
greatest acceleration will occur from rest, where the tires have the
greatest friction and there is the absence of all drag.
"Mayf. . .And the torque being applied to the tire and track is greater as
the car goes doen the track because the tire grows like a son of a gun at
top end. Lots of parameters to mess with."
Don't think so. As the torque arm grows, torque application is less. 5,000
lbs/1 ft or 5,000 lbs/2 FT. Which is less? Elon
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