IHADAV8.com - Turbo Buick Tech, and Nonsense
Tech Area => General Buick Tech => Topic started by: Shimy87 on September 21 2018, 12:59:51 PM
-
I got my new rears installed and they are 28 inches tall. stock tranny and rear end, is there a way to calculate how far off my speedo is now. Reading 60 on the speedometer seems like Im going closer to 70.
Thanks!
-
https://tiresize.com/calculator/ (https://tiresize.com/calculator/)
compare the old/new tires
https://tiresize.com/speedometer-calibration/
-
perfect...than ks...chart says old tires 60 mph/ new one 67.5
-
It's about 8% off. Go to a 27 tooth speedometer gear and it will read right.
That is a black gear if that helps. Takes about three minutes to change and one more minute to clean up the fluid that leaks out of the tranny which you pull the original out
-
Set your GPS to show your speed. Click the left scanmaster button 6 times and make it read 100.
Whatever your GPS says is your actual real world error. :)
-
my car wont go 100 :icon_eyes: :cheers:
-
Although the correct speedometer gear for 28" tires is the 27 tooth black gear, I'm going to post this link as it has all the gears listed at the end. Remember we want the ones for the 200-r4
https://www.hotrod.com/articles/calibrate-gm-mechanical-speedometers/amp/ (https://www.hotrod.com/articles/calibrate-gm-mechanical-speedometers/amp/)
-
Those are some nice charts
-
Funny this topic has come up. I been trying to figure out a speed sensor on the Vega
Our computer needs a 2000 ppm signal and a lot of aftermarket VSS or between 4000 and 16000.
I found a GPS that is programable and I spoke to the manufacturer and they will set it up for me so it has the correct signal for my computer. The nice thing is a won’t have to worry about tire size or gear ratio and I can use the low gear timing and fueling adjustments in my old chip and my poor mans edash will have a work speedo again
Sent from my iPhone using Tapatalk Pro
-
http://store.centrodyne.com/store/Z063-Speed-Signal-Divider-P72.aspx (http://store.centrodyne.com/store/Z063-Speed-Signal-Divider-P72.aspx)
http://ielectron.ca/index.php?route=product/category&path=25 (http://ielectron.ca/index.php?route=product/category&path=25)
-
Thanks Dave that is a handy little unit. Cost effective too still need a speed sensor they are pretty inexpensive also.
My thought with the GPS is it’s once and done it will automatically compensate for any changes I make to the car down the road
Sent from my iPhone using Tapatalk Pro
-
Will gps update fast enough to work?
-
We will soon find out
Sent from my iPhone using Tapatalk Pro
-
What do you think 10hz update rate.
https://c-a-i.net/skydrive
Sent from my iPhone using Tapatalk Pro
-
I would like to think ten times a second will keep up with acceleration. I guess proof will be in the pudd'n.
that is probably as fast, or faster, than a vss samples
-
I wonder what it does when the GPS looses lock or during acquisition.
-
Well I just thought I would report back on the sky drive GPS.
It works as advertised easy to wire up to my computer. It’s a little slow at low speed. Drops off under about 10 mph but once it’s going it works well.
Should be more than enough to operate lock up and eliminate codes if you have a flakey VSS.
I gonna post a a thread for Eric with a log to see if he thinks it’s good enough use for fuelling and timing in 1st and second gear with one of his chips.
Sent from my iPhone using Tapatalk Pro
-
sounds good. Just don't race anyone in a tunnel :D
-
Should work good enough. For right at a decade since I got into speedboats, the hot ticket is to have a GPS speedo.
Granted that's to verify actual top speed and boats don't spend a lot of time in tunnels, but I can't imagine you could blow an engine at 8% throttle if the GPS doesn't report to the chip for a few sexonds.
-
Worse thing that could happen is maybe a code I think if it lost its signal.
Sent from my iPhone using Tapatalk Pro