do the 4.10s change the speedometer reading because my car is saying im goin faster than i actually am it was fine but i did the exhaust and gears at the same time and i know the exhaust didnt do it so is it the gears or a coincidence

 

u need a speed cal. its the gears.

 

get a tuner and change it to to 4.10 so the comp can recalibrate

 

Your speed is now off by 20%. It reads high.

 

what yr car do you have? if its a 98 older you can buy a cheap speedo gear and be done.

 

he has an 01 auto. so he needs a tuner, the speed cal wont work, and neither will the speedo gear.

 

ok then yes i suggest a Tuner. the speedcal should work. but i just don't like them.

 

for some reason speedcals only work on manuals...which pretty much sucks if you have an auto(forced to get a $400 tuner). but at least with the tuner it will help the tranny shift a bit better now, and pick up a cople hp.

 

400 for a tuner how much hp gains will i get from it

 

depending on mods. if stock i would imagine 5-10rwhp at most...nothing huge, but a small little bump.

 

i got a borla exhaust k&N cai and the 4.10's

 

sorry off topic but how much u pay for the borla

 

it will still be really close to 10rwhp, nothing mind blowing, but a small little increase that is a nice bonus when having to get your speedo corrected.

 

it costed me out the *** 800 but i got it put on and welded free with me gears but still ridiculous for exhaust