DC2R RPM - Speed Question..

[DC:53:XX]

just wondering what kph reading u guys get from ur dc2r's in 5th gear at 100kph

maby its cumming from a 6 speed to a 5 speed but i think the revs are a bit high? and i can head a running diff/lsd/final drive sound on lower rpms.. have had friends tell me so aswell, and it isnt my gear box..
my cars clocked only 106thou kms and iv never heared a single gear box crunch while changing gears what so ever..

i think at 100kpm in 5th gear im at roughly 3,750 rpm.. seems a little high for me..

[DC2RKID]

just wondering what kph reading u guys get from ur dc2r's in 5th gear at 100kph

maby its cumming from a 6 speed to a 5 speed but i think the revs are a bit high? and i can head a running diff/lsd/final drive sound on lower rpms.. have had friends tell me so aswell, and it isnt my gear box..
my cars clocked only 106thou kms and iv never heared a single gear box crunch while changing gears what so ever..

i think at 100kpm in 5th gear im at roughly 3,750 rpm.. seems a little high for me..

mines round the same revs man....lol need an extra gear ey! and my gearbox make the same noise...im just gunna change oil and put some nulon G70 in the reason u can prob hear box is cause of no carpet underlay! i dunno

[xQuizit]

3,750 wow, mine sits at 3500 or just a little over going at 100kph

[m0nty]

A ten year old mechanical tachometer cannot be taken as gospel. Proper measurement can only reaaly be done with EMS. It's the same scenario as the DC5 fuel cut. Slot of people claim higher than 7900rpm but the needle isn't acurate enough to go off for proper comparison.

[DC:53:XX]

i know excatly what ur saying monty,
should of mentioned before i got my readings from using an my Rsm and VAFC2..

[tinkerbell]

stock tyre size?

this can effect it too, but not be heaps...

have a play with this:

http://www.miata.net/garage/tirecalc.html

[jj17]

stock tyre size?

this can effect it too, but not be heaps...

have a play with this:

http://www.miata.net/garage/tirecalc.html

interesting.. so this is what was happening. any idea if you can re calibrate the speedo to make it accurate after changing tyre sizes?

[tinkerbell]

interesting.. so this is what was happening. any idea if you can re calibrate the speedo to make it accurate after changing tyre sizes?

no, dont think so...

just calibrate your mind... you just need to do the calc and remember it...

[tinkerbell]

for example, i went from 195/55-15 to 205/50-16

this is 2.7% increase by the calculator

so at 60 = 60/0.027+60 = 61.62km/h

at 100 = 100/0.027+100= 102.7km/h

BUT there might be differences between manufactures too...

PLUS the diameter of a new tyre is more than a fairly bald one, by like ~12mm (6mm + 6mm)

so in my example, the bald tyre will be back close to the OEM new tyre size...

[tinkerbell]

i think at 100kpm in 5th gear im at roughly 3,750 rpm.. seems a little high for me..

use this to calculate proper RPM vs SPEED

http://quick99si.home.comcast.net/misc/gearcalc.xls

you need to know the ITR ratios:

1st: 3.230
2nd:2.105
3rd:1.458
4th:1.034
5th:0.787
R: 3.000
FD: 4.785

[tinkerbell]

or use this one!

http://members.iinet.net.au/%7Echenglee/GearRatio.xls

i forgot about it! it is in KMH not MPH

it has all the ITR ratios prefilled,

shows with 205/50-15 tyres you are doing 100kmh at 3409rpm

[DC2RKID]

well really the wheel dia is the only thing that would make ur speedo reading any diff to any other dc2r ey...unless ur playing with ratios

[on boost]

mate his is very normal for a dc2R. Im on my second dc2r and it is exactly the same, most of the time im in 5th while doing 60kph. They have very high strug engines and gear boxes, because they were designed for track use and not so much just crusising on the high way.

[DC2RKID]

mate his is very normal for a dc2R. Im on my second dc2r and it is exactly the same, most of the time im in 5th while doing 60kph. They have very high strug engines and gear boxes, because they were designed for track use and not so much just crusising on the high way.

yeah could u imagine if the ratios were like any other normal car!! and gettin the thing to redline in 5th gear!! youd hit 300+ haha eventually!

[ek9rx]

yeah could u imagine if the ratios were like any other normal car!! and gettin the thing to redline in 5th gear!! youd hit 300+ haha eventually!

lol 5th gear redline