YotaTech Forums

YotaTech Forums (https://www.yotatech.com/forums/)
-   86-95 Trucks & 4Runners (https://www.yotatech.com/forums/f116/)
-   -   Is my speedo off? (https://www.yotatech.com/forums/f116/my-speedo-off-131159/)

AE86GTS 11-30-2007 10:29 PM

Is my speedo off?
 
so there's my line up! 1987 turbo 4 runner! swapped to manual not done by me!
had a 430 in the rear! but was 410 in front so i fixxed that now its back to factory 410's! like engine bay tag says!

I'm running 30x9.50 tires on 15's

and has digital dash!

At 2000 RPM in 5th i'm doing about 49 to 51mph!
At 3000 RPM in 5th i'm doing 69 to 70 mph!

does that sound right

of do i have the wrong speedo gear?

jason191918 11-30-2007 10:31 PM

If you know your tranny and tcase ratios, you can use this:

http://www.4lo.com/4LoCalc.htm

notanymore 11-30-2007 11:08 PM

here is another gear/speed calc http://www.grimmjeeper.com/gears.html

DeathCougar 11-30-2007 11:10 PM

Sounds about right to me. My 86 4Runner does about 2800-3000rpm at 65-70 mph.

AE86GTS 12-01-2007 08:02 AM

I have no idea what my trans and Tcase ratios are!

DeathCougar 12-01-2007 09:42 AM

what did the manual trans come out of?

1eye 12-01-2007 10:04 AM

Option#1: Grab your GPS{or someone's} and go for a spin. Mine is accurate to within 1% in the speed setting{that better than most stock speedos}.
Option#2: For you country people:) , 60mph takes you 1 mile in 1 min.
Lots/most of the "grid" roads are layed out in the mile system. Should be able to tell how close your speedo is.

AE86GTS 12-01-2007 02:14 PM

oh its the r151e out of the turbo truck my buddy parted out dues to super bad rust that where the trans in from i would guess the same on the transfer case but i'll have to ask!

notanymore 12-01-2007 02:30 PM

for highway speeds your tcase ratio is just 1:1. unless you make a habbit of driving around in 4lo

DeathCougar 12-01-2007 02:36 PM

well it would be the R151F (not the E)

ratios are:

First Gear: 4.313:1
Second Gear: 2.330:1
Third Gear: 1.436:1
Fourth Gear: 1.00:1
Fifth Gear: 0.838:1

T case ratio is:

2HI and 4HI: 1:1
4LO: 2.28:1

AE86GTS 12-01-2007 04:09 PM

hmm so can i pick another speedo gear for the trans some where like from a different truck with a different factory gear!?

EWAYota 12-01-2007 09:57 PM

or you could just follow a buddy or family member and pace them..... Mine's been off for years. I just jot down the speeds I'm showing to what they really are and go off by that. Someday I'll have a gps to make it a bit easier.

seafarinman 12-01-2007 10:03 PM

I recently got some 5.29's in my v6 thirds and I am running 37" MTR's and my speedo is still correct. I noticed that when I was running 31's and 4.10's it was correct as well.

AE86GTS 12-02-2007 09:51 AM

ok well i'm looking to fix the problem not beat around it

DeathCougar 12-02-2007 10:02 AM

sounds like its correct to me. Since all turbo trucks whether they are auto or manual use stock 4.10 gearing, the speedo gear shouldn't matter. Get out on the freeway and try using the mile markers to figure it out. Keep it at 60mph between the markers, and as suggested above it should take you 1 minute per mile. Any large variance and you know you have a problem with your speedo or gear.

AE86GTS 12-02-2007 04:29 PM

i'll see what i can do!


All times are GMT -8. The time now is 10:26 PM.


© 2024 MH Sub I, LLC dba Internet Brands