You are right.3771489 wrote:
Btw 0,854 is from 520/4 or 520A/4
Speedometer correction factors
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- Newbee
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Speedo correction factor
Hope you don't mind me replying to this old post, but as you appear to be the resident expert on these matters...
I have 2 problems with my speedo:
Chronic: speedo wavers from rest up to speed then settles.
Acute: the mileometer and trip meter stopped turning today.
My mechanic has advised replacing the speedo as he is unable to fix the gears and a friend told me that replacing the cable would stop the juddering needle problem.
Going with this advice to replace both, I just want to make sure I get the right parts !
I have a 1982 UK 323i automatic. I have standard 5.5x13 wheels shod with 205/60 R13 86H tyres all round. Taking into account the non-standard tyres, is there a more appropriate speedo to get than the one I currently have ? ( W = 1.220 EG )
Kind regards, H
I have 2 problems with my speedo:
Chronic: speedo wavers from rest up to speed then settles.
Acute: the mileometer and trip meter stopped turning today.
My mechanic has advised replacing the speedo as he is unable to fix the gears and a friend told me that replacing the cable would stop the juddering needle problem.
Going with this advice to replace both, I just want to make sure I get the right parts !
I have a 1982 UK 323i automatic. I have standard 5.5x13 wheels shod with 205/60 R13 86H tyres all round. Taking into account the non-standard tyres, is there a more appropriate speedo to get than the one I currently have ? ( W = 1.220 EG )
Kind regards, H
Mine is a 323i, build 3/1981. Has a 5 speed sport and limited slip diff.
W 0,762
According to my GPS, 1 KM off.
Tyres 195-55-15
W 0,762
According to my GPS, 1 KM off.
Tyres 195-55-15
Last edited by Arnold D on Tue Mar 23, 2010 10:16 am, edited 1 time in total.
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- Peter V.
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Mine is a 323i with an Eco-fivespeed gearbox and a standard 3.45 diff
W = 0762
According to the tomtom it is right-on. The original tyresetting so 185/70 13.
W = 0762
According to the tomtom it is right-on. The original tyresetting so 185/70 13.
Gr Peter V.
.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.
BMW E21, 1981 320/6 Ascot Grau.
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BMW F31, 2017 320dA EDE Luxuryline Mineral Grau.
.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.
BMW E21, 1981 320/6 Ascot Grau.
BMW E85, 2004 Z4 2.5i Sterling Grau.
BMW F31, 2017 320dA EDE Luxuryline Mineral Grau.
- mcjjordan
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Re: Speedometer correction factors
1.393
1980 316 4 speed uk mph
it screams on motorway!!! really too high revving
1980 316 4 speed uk mph
it screams on motorway!!! really too high revving
- Jeroen
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Re: Speedometer correction factors
Fits the list posted previously I guess:
1,465 0-120 315,316,318,318A 4,10 or 4,11
1,393 0-120 320(A)/4,316(A)1.8,318i(A),320(A)1.8i 3,91
1,300 0-140 320i(2.0iA(US)),320(A)/6 3,64
1,220 0-140 323i 3,45
1,360 0-140 320i(1.8i)US 3,91
1,266 0-140 320iA(1.8i(US)) 3,64
1,465 0-120 315,316,318,318A 4,10 or 4,11
1,393 0-120 320(A)/4,316(A)1.8,318i(A),320(A)1.8i 3,91
1,300 0-140 320i(2.0iA(US)),320(A)/6 3,64
1,220 0-140 323i 3,45
1,360 0-140 320i(1.8i)US 3,91
1,266 0-140 320iA(1.8i(US)) 3,64
Regards/groeten, Jeroen
- mcjjordan
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Re: Speedometer correction factors
mcjjordan wrote:1.393
1980 316 4 speed uk mph
it screams on motorway!!! really too high revving
70mph its revving at 4000rpm!
- mcjjordan
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Re: Speedometer correction factors
found a lovely calculator for working out variants
http://johnmaherracing.com/calculators/ ... alculator/
http://johnmaherracing.com/calculators/ ... alculator/
- mcjjordan
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Re: Speedometer correction factors
So i have 2 speedos
1393 & 1300
So what diff ratios are these for?
1393 & 1300
So what diff ratios are these for?
- petroscf
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Re: Speedometer correction factors
My car original speedo is the one without anything written on it. (Pre facelift 316 1.6 with 4 speed manual and 4.10 open diff)
With the engine (and diff and gearbox) swap the new set up is: W=0762eg speedo, with 3.64 diff and sport 5 speed gearbox (5th gear is 1:1)
So I guess that my current speedo is probably from a 323i, thus, made ideally to match a 3.45 diff?
How should these correction factors be interpreted exactly? I haven't understood
With the engine (and diff and gearbox) swap the new set up is: W=0762eg speedo, with 3.64 diff and sport 5 speed gearbox (5th gear is 1:1)
So I guess that my current speedo is probably from a 323i, thus, made ideally to match a 3.45 diff?
How should these correction factors be interpreted exactly? I haven't understood
/oo=00=oo\
E21 Forever
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Re: Speedometer correction factors
Simple example: You have a speedo with w=0762, this means on 1000m Your diff turns 762 times (if it's the right 3.45). That's what Your speedo expects.
If You have a 762 speedo and a 3.64 diff, Your Diff turns faster, than the speedo expects, so Your speed is shown up higher, than is is.
0808 to 762 in this case..means 5.7% faster than real speed.
If You have a 762 speedo and a 3.64 diff, Your Diff turns faster, than the speedo expects, so Your speed is shown up higher, than is is.
0808 to 762 in this case..means 5.7% faster than real speed.
- petroscf
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Re: Speedometer correction factors
Indeed!!
And based on a couple of comparisons I've done with gps, it seems you're right!
However, isn't all this also depending on wheels diameter?
And based on a couple of comparisons I've done with gps, it seems you're right!
However, isn't all this also depending on wheels diameter?
/oo=00=oo\
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