just bought a 97 f150 4.2
I've stretched my 1st to 45 once but it sounds terrible and dont believe I'll ever do that again
you can actually feel it LOSING power.
-or-
you can get a computer that plugs into the OBII connector underneath the dash and get a digital tach. its not as fast as a real-time tach, but it updates every second and is useful on the highway to monitoring fuel use
Guess my engine was built on a Tuesday, cause at 158,000 miles, I have had zero problems, except the *&%^ ECU and a P0443 fault. 1997 V6 4.2 I'd knock on wood, but there's only plastic on board. Keeping my fingers crossed then.
my 04 heritage 4.2L 5spd had 3.08 gears and 235-75/16
1st-40ish
2nd-65ish
3rd-90ish
4th-110+( had mine at about 108 according to tach because speedo stops at 100. but i counted how many rpms it took in 4th to go 5mph faster. altho i cant remember now but i figured 108mph.
here's how...
1-hold in trip odometer button.
2-turn key to on(dont start)
3-after about 5 seconds your odometer reading should change and say "test"
4-let go of trip button just press the button over and over until it says "tach" or "tac" then start vehicle. the odometer will go blank while starting but it will come up in tach and it will have a number. you will not be able to read the last digit.
5-you will not be able to access you odometer again after you do this until the truck is turned off. it resets back to the odometer every shut off so you have to do this every time
my aftermarket tach said my engine was limited at 5400rpms and it idled between 750 and 850. i never used my a/c.
if you have any questions feel free to ask. if i know the answer i'll tell you





