Why is my car revving high in 3rd gear

aye i got a 92 V6 4.3 Pickup truck , ive only had it for less than a week and i put a flex fan (replacing the clutch fan) and a High Flow racing filter. Well tonight i was racing a 91 Toyota Mr2 and i was beating him ... when my car went to 3rd gear it went all the way up to the redline .... i got electric rpm gauge and i dont trust it .. it sayd i was redline and i got nervous and backed off and of course he smashed on meeh ... i dont kno the max speed for 3rd gear but when i let off it shifted and i punched it and it went up to the 80's before i left off again .. but i was at 75 in 3rd gear and i dont wanna blow my motor .. is this common ? do i just keep full throttle till it shifts .. cuz my dad bought me a racing tach to stick on the side ... Please give meeh yo advice

what are u asking? when your truck shifted in 3rd did the truck accelerate or did the rpm just go up with out any acceleration? or are u asking if it is normal that the trans didnt shift at redline in 3rd gear. the answer is no it is not normal if it didnt shift at redline.

yeah thats wut im asking ... it didnt shift at redline ... so my friend said it was the transmission.