that is covered in my axle speed page, it shows, the speed at 3000 rpm in all gears, and all permuations if engine ,trans and axle.
in your case that be this. (stock tires, or not. as that changes speeds, for sure)
the math is easy, i have that posted there, (tire circumference is the 1 variable, all else is KNOWN)
see this page, see that your car is 4.62:1 axle, so that means 3000 rpm is 3rd gear, and 52mph, stock tires, the 8v goes slower with that axle, all do. (compared to the 16v engine)
then see chart 2? for wrong tires. i did the math there too.
17% faster with 33" tires, see that? or 60mph with 33" tires, 1.17x 52...
keep in mind those number are all with the TCC locked up, if not, the TC slips and no man on earth can guess that...(temp and load dependent, is that slip)
http://www.fixkick.com/part-time-test.html#SPEED
now this, ever seen the hydr, schematic of the 3l30
here it is.
see this line marked blue that is GOV pressure out put line this pressure rises as cars speed goes faster, the gov converts tail RPM to pressure on that line, the higher the pressure
the sooner it shifts. but note that it then passes through the MODULATOR to the DRIVE line red.
the modulator changes the pressure on both lines, it can even leak pressure, (fluid bypass) to the pan, and cause late shifting based on vacuum engine load.
this is how this beast works. see scary drawing, here.
http://www.fixkick.com/tranny/slush/slid...age_2.html
so what is the math on 70mph. ???
here is the equation off my gears page. (it's only really just 2 things, axle rpm and tire circumference.) both are know at all times. (tranny not slipping)
seems complex and is not. at all.
and the conversion of minutes (rpm) to hours, (MPH)
lets do that.
what are those constants below. 5280 is feet to mile. , 12 is inches in foot.
and 60 is minutes to an hour.
ratio is
algebra1:
MPH = (((( RPM ÷ total ratio) X circum") ÷ 12) x60) ÷ 5280
stock tire is 85.1" circum. a fact, no guessing, one can even use a tape measure to prove that. (or C= pi x D) (D is tire diameter outside , not rim)
total ratio in Locked up 3rd gear is 4.62, same as rear axle ratio. tranny is 1:1 in 3rd gear 1spin in, and 1 spin out....
that means engine spins 4.62 times to get 1 turn on axle. (or if engine pins 4.62 times, axle turns turn only)
easy no?
why not just do 6000 rpm max rpm? we already know 6k , its 3k times 2.
that be 52 mphx 2 , or 104 miles per hour,at k6 RPM after all 3000 is 52 and 2 times that is 6000 rpm.
but what is 70?, well one could do the equation or just interpolate that, it's a linear function.,
using interpolation shows 4038 rpm. = 70, in 3rd gear, locked up.
as seen here. pump in 4 numbers and bam. 52,104,3000,6000 equate.
https://www.easycalculation.com/analytic...lation.php
now lets work that backwards
as we did in the old days with teacher swinging a ruler,,,, Class show you work or get zero credit....
4023 div by 4.62 is 874 axle rpm
so 85.1" circum. is 74379 inches in 1minute. (all done on a 4 banger calculator)
div by 12 is feet a minute. is 6198 feet per minute (getting closer)
and x60 is feet per hour or 371898 FPH (feet per hour)
divided by, 5,280 gives. me 70.4mph.(feet to mile)
there i did the math both ways, by equation and by interpolation.
answer was,, 4038 RPM.
you can hear and feel all 3 gears
and the TCC lockup.
and unlock,
all but unlock are predictable RPM.
this car is no 300hp Chevy that pulls, 3;1 axle gears, not by a long shot.
