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Possible speedo error?

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Old Dec 10, 2007 | 05:39 PM
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87 300D
Possible speedo error?

I picked up my 300D today and drove it down the 407 tollway and I realize traffic moves at a good clip but I was doing 120k and almost everything passed me. My Q is what speed are you folks getting at RPMs?
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Old Dec 10, 2007 | 06:28 PM
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You shouldn't have been trying to do 120 in the first place.


The RPMs should be around 3000rpm at 65mph.
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Old Dec 10, 2007 | 06:48 PM
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87 300D
Thats funny. The 120 is Kilometers per hour, thats how road speed is measured in Canada. The 65 comparo though is about right.
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Old Dec 10, 2007 | 06:52 PM
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87 300D
Come to think of it 120 KPH is more like 72 -75 mph. The car is an 87 turbo
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Old Dec 10, 2007 | 09:36 PM
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Originally Posted by Jim7
I picked up my 300D today and drove it down the 407 tollway and I realize traffic moves at a good clip but I was doing 120k and almost everything passed me. My Q is what speed are you folks getting at RPMs?
Are you referring to the 407 ETR? Everyone does 160 kph despite self-righteous OPPs like Cam Wooley hidding under every bridge. 120 kph is nothing for your diesel. I guess when I am doing that in my 5 speed the engine is revving well under 3,000 rpm.
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Old Dec 10, 2007 | 10:53 PM
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Just simply cross-check the speedometer with a GPS unit to determine the accuracy.

Also, 70 mph should be around 2650 rpm in an '87 300D. About 2800 rpm is 75 mph or 120 kph. This is assuming a flat surface. There is no lockup clutch on this model, so there is always a bit of slip in the torque converter.
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Old Dec 10, 2007 | 11:11 PM
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87 300D
Now thats helpful.
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Old Dec 11, 2007 | 11:11 AM
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Originally Posted by Jim7
Thats funny. The 120 is Kilometers per hour, thats how road speed is measured in Canada. The 65 comparo though is about right.
You didn't say in your first post where you are or have it in your profile.
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Old Dec 11, 2007 | 07:44 PM
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Originally Posted by 240D 3.0T
You didn't say in your first post where you are or have it in your profile.
He is a Canuck alright living around Toronto as he travels on the electronic toll road Hwy 407.

There are lots of diesel cars and trucks in the Greater Toronto Area (GTA) most of them VW Jetta TDis with stick shift. Like the USA there are less Golfs for some reason. Next are the older MB diesel work horses and lastly the work trucks up northern Ontario. The farmers love Ford Powerstrokes, Duramaxes and Cummins, roughly in that order. With the frigid conditions there it is amazing diesels are still so popular. I guess it has something to do with the availability of red diesel.
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Old Jan 14, 2008 | 06:02 PM
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87 300D
Long story short. I was on the QEW driving next to a Civic and it has large dash readout that I could see easily and I matched speed and his display was 92 kph and I was a tad over 100. So I'd guess my wheel/tire combo is a bit off.
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