hey i have a TurboII Transmission on my GXL. i just recently got the Speedo working and im wondering if its reading incorrect since there 2 different kinds.

it feels incorrect? but im not sure... i dont know my sense of speed.
if its off by a little then no worries.

someone told me to go to this site to plug in the gear ratios and stuff but that didnt help too much. i dont think i plugged in the numbers right...

tell me if this is right when you guys are driving.
...in 5th Gear, 4000RPM's, and it reads 80MPH.

 

I have an 88 'vert (n/a motor) and a tII tranny & rear end, and my speedo is accurate (verified by cop radar sign and buddy pacing me calling out speeds on cell phone)


Hope this helps (also have stock 88 n/a gauge cluster)

 

well what year is ur TurboII tranny? maybe they have the same gear size on the sending gear of the speedo.

im not sure.

 

4000@80 seems right to me.

 

I've got a S5 N/A with a S4 TII tranny and a 3.90 auto rear end and somewhow its accurate.

 

I have a NA rear end and TII tranny. Speedo if fine.

Confirmed by Cop as well. 70+ in a 40 oops!

 

what do you mean by rear end? like the differential? or wat

 

Yes, the diff. And my n/a motor is s4, trans and rear is s5 turbo.

 

I have a T2 diff, tranny and engine in my Vert, but my 80mph reads 3500rpm? not 4000. Maybe mines off? My old vert tranny and diff read 3000 at 80mph?

 

What year TII tranny? If you have an S4 and stock tire sizes and a 4.1 rear end then that 4000 rpm @ 80 mph is way off. If you have an S5 and stock tire sizes and a 4.1 rear end then 4000 rpm @ 80 mph is even farther off.

By my program, 4000 rpm would correspond to 94 mph and 99 mph respectively for a S4 fifth gear and an S5 fifth gear. This is of course assuming stock 205/60-15 tires and a 4.1 rear end. If those numbers are different, then we need to know them to tell whether your speedo is off or not.