View Full Version : Speedometer

06-11-2011, 05:20 AM
I'm 3SGE Beams Redtop swapped and I've having difficulty figuring this out. I bought the car swapped from San Diego. I believe my speedometer is off because I GPS'ed the speed on the freeway and it read 89 when it said 85 mph on my speedo in 3rd gear. From what I've heard is that 3rd gear is supposed to be evenly matched with your speedometer. As some of you may know this is an japanese engine so the speedometer used to read out in KPH. I shop down in san diego called Pan Auto put a speed converter (I don't know how they did it)

I was just told on 6gc that ever since I installed the helical lsd transmission that it affects the final drive gear ratio. These are the gears for the S54 Transmission:

3.285 * 4.176 = 2027.5 - 37 mph
1.960 * 4.176 = 1209.7 - 62 mph
1.322 * 4.176 = 815.9 - 91 mph
1.028 * 4.176 = 634.5 - 118 mph
0.820 * 4.176 = 506.1 - 147 mph

here is my video for proof:
http://i483.photobucket.com/albums/rr197/BonzaiCelica/1999%20Celica%20GT/th_VIDEO0002.jpg (http://s483.photobucket.com/albums/rr197/BonzaiCelica/1999%20Celica%20GT/?action=view&current=VIDEO0002.mp4)

06-12-2011, 04:26 AM
what size tires do you have?

06-20-2011, 10:05 AM
I figured it out. Turns out that since S54 FWD 94-99 Celica Transmission and C160 and C60 Celica GT and GT-S models share the same differentials; I actually have a 4.529 final drive ratio. The guy I bought the Helical Transmission told me the gearing was left unchanged. I think when he had the shop install the Helical LSD they either put in a different Ring and Pinion Gear or it already had one installed in it. Yes I already did all my calculations with this website. I have 205/45R16 tires. http://www.boosttown.com/gearbox_differential/speed_calculator.php