Hey I got a quick question. I was on my way to LA from N. Cal on I-5 I had my a few mods and a Nelson tune in me 20 inch rim 2001 Tahoe . I had this A$$hole in another tahoe riding my A$$at 95 mph I got tired of him riding my A$$ so punched it and left his A$$ about 1/2 mile to almost a mile behind when I looked in the rearview when I punched it my tahoe just freakin jumped and the *** end squatted and took off like a bullet that dude's eyes in the other Tahoe were the size of golf ***** and I saw him say like "What The" . The Nelson tune is no freakin joke my speedo only goes to 100 mph just wondering my Mph at 5700 to 5800 rpm and it was still pulling hard on topend and the gas mileage was good from what I was getting before. With a few bolt-on mods and tune I got 601 miles to a full tank all freeway light to no traffic.

 

what gears do you hav ein the rear and what size tires are you running?

 

You were going nearly130MPH I'm assuming you were in 3rd,because 4th at 5700 would be 170MPH+,if you want calculate your true speed go to www.smokemup.com and calculate your tire diameters then plug that with your rear geat ratio into their speed in gears calculator.

 

Tires 265-50-20 rear gears 3.42 I did the auto math on 'smokem' and it was about 145 mph. Yes it was in 3rd ..Thanks just been wondering about the speed.

 

i was messing with a friend of mine yesterday. he has a 92 gmc. 4.3 ahha.
i left him pretty good! just for fun.
i was rolling the weird thing is i have a hypertec i thought that it limited my truck to 128? i have 255/75/16 tires with 3.42 gears. i had my tach on 6k in 3rd gear.(i know it was in 3rd because it shifts out of 2nd at 92-93.) what would that be in mph. im like tahoe dude my speedo stops on 100 and it was on that little peg.) so i just watch the tach rise. but 128 in third? it wouldnt be 6k rpm would it? it felt like it was still tryin to go. i tried to go to that gosmokem.com but it wouldnt let me register.

 

If you would like to figure out your speed based on RPM just see how many MPH it jumps up from a lower RPM like from 2000-3000 that registeres on your speedo in the same gear and do the math. As long as your in the same gear it should be consistent.