other night i did a WOT run and got it ot 6400rpms in 3rd [4l60e] and it seemed like it didnt go any faster. could this been the mph limit the tune has? i was no where near my rev limter and truck wasnt slipping.

i run 410s, 30" stock height tires but have no clue what MPH i was at since my speedo stops at 100 and was pegged at like 4400k rpms in 3rd so from there on i was pegged and had no clue how fast i was going. now iprobably could of shifted into 4th but didnt.

but any clue on how fast that was? i know when i had 373s and stock setup about 5800 was like 128

ohwell whats some rpms/mph some ppl are seeing

 

6400 engine rpm / 1.00 tranny gear ratio = 6400 driveshaft rpm
6400 driveshaft rpm / 4.10 gear ratio = 1561 axle rpm = 1561 tire rpm
30" dia tire = 94.25" circumference
94.25" x 1561 tire rpm = 147121 inches per minute
147121 inches per minute = 8827240 inches per hour
8827240 inches per hour = 139 mph

 

sweet!!! thanks man, and to think i was afraid of running out of gear in the 1/4 on spray.

to much math for me but its good to know what MPH in theroy i was going. 139 is a nice mph and truck felt stable

so what are some others top mph?

 

if you had hit the speed limiter you would have felt it shut down and come back after it dropped a few mph, so it wasn't that. You may have just hit an aerodynamic wall. I could only muster 138 out of my truck, but that was when I shifted to 4th and it wouldn't pull beyond that.

 

i did a speed test with my friend in his supra and i got up to 140 mph. still had a little room to go but didn't want to push it with the stock tires on.... that scared the **** out of me those tiers were humming so loud i thought they were going to blow

 

i would have said 140 even before seeing thunder's calculations b/c we both have the same gear and tire height. been there done that. and yes the truck was barely pulling at that speed.

 

I get to about 135-138 and when it tops out.... I spray it LOL... it pulls a little harder then (sometimes even the floorboard drops out of it LOL)

 

140+ before dont know exactly road was going by too fast to watch the tach

 

I've buried it somewhere over 120 shifting 3 -> 4.
It's funny how once the trucks get rolling they just keep going. In my Z06 the car slows down with the engine speed. Such a different ride.

 

aerodynamic wall= 138mph
Dyno no wall= 147mph......6000rpms 3rd gear.