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I'll nevAr go single!
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Discussion Starter · #1 ·
I have a R-154 that has the gearing thing inside for the 4.10 diff, though I'm using the stock 4.30.

I know that at about 40mph I saw a radar thing say I was going 33mph.

Is their some kinda calculation I can do to see how fast im really going, or what the difference is at different speeds?
 

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It's really easy. Divide 4.3 by 4.1 - That comes to approximately 1.05, which means that your speedometer is 5 percent off. The rest of the difference is the fact that Toyota "underclocks" their speedometers, to be low by a few MPH. Your odometer should be dead-on, plus 5 percent.
 

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I'll nevAr go single!
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Discussion Starter · #3 ·
Hmmm, so if I was going 40mph as the spedo says, then I'm really going 38?
Cause the radar thing im sure said 33.
 

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BMM
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I dont really understand how Thermactor ended up with 5%....

but i wouldnt totally rely on those radars.
 

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BMM
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90beater said:
Radar displays are way off. I drove by two in one day. One was 1mph over, the other was 8mph under.
yeah, exactly. whenever i drive by one i see how high i can get them :sadance:
 

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I'll nevAr go single!
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Discussion Starter · #8 ·
Hmm, well, ok.
I dunno though, cause when I drive on the freeway doing 65, it dosnt seem like im going that fast.... Guess I'll just get a friend to pace me and see what comes of it.
 

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Boostedmkiii said:
I dont really understand how Thermactor ended up with 5%....

but i wouldnt totally rely on those radars.
Actually it's 4.65%, but 5% is close enough. He's still basically right.
 

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I'll nevAr go single!
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Discussion Starter · #10 ·
Ok, I havnt had the chance to have a friend pace me yet (Lacking in that area lol)

But, another thing I just realised today.

Before, I hit 120Mph at about 4KRpm in 5th gear, have done this a couple times and its always the same.

But, I believe this morning I hit my Speed Cut (Aparently, 1JZ ECU has a Speedcut at 110Mph)

I was going over 120Mph for sure, as I was at 5KRpm.....
This is annoying.....
 

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I was driving 40mph and the radar said I was going 35 mph... so now I always drive 5 mph over the speed limit. haha... but one thing I noticed now is that I feel like I'm going a little bit too fast.
 

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Not so fast!
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Boostedmkiii said:
yeah, exactly. whenever i drive by one i see how high i can get them :sadance:
Hope you double-check to make sure it aint photo radar ;)

I know my speedo is off for the fact my laptops gps navigation has speed display. 65 on the speedometer is about 62 on GPS.
 
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