What Would You Believe

[Adz2332]

Hey all,

I just got a heap of stuff installed into my 33 GTR.

One of which was a Power FC and controller.

When i look at the controller it reads different to what the standered tacho and speedo reads.

Its around 5 to 10 kmph on the speedo and around 500 in the revs.

Which would be more accurate?

Which would you trust??

[PAV34]

FC

[Adz2332]

Are you 100 % sure on that?

Because id like to keep my shifting under say 7500 to 7000 revs.... and going by the power fc im only changing at around 6500.

And if the fc is wrong and the tacho is right i dont want to let it get around 8000 revs!

[PAV34]

Your gauges could be off which is not uncommon in Skylines.

Sensors maybe?

[Adz2332]

If it is the gauges i dont mind. it can stay like it. i look at the power fc most of the time... just making sure thats all.

Will the power fc be as accurate when i put the bigger wheels on? as i know thatll throw out the speedo but will it throw the fc to?

[paulr33]

both are reading from the same source, the gearbox speedo drive

the standard dials will be out (wear and tear) and the FC will be spot on

[Sklyn]

Can I expect this to be the same with my Turbo timer for speed?

up to about 60km/h they are the same but over that and the speed shown on the timer is less than the speed shown on the dash..

I have tried re-calibrating the timer but doesn't seem to help.

[blind_elk]

The tacho / speedo are basically mechanical displays, and are subject tto inaccuracy through wear-and-tear.

The FC / TT are electronic, and not subject to wear-and-tear.

I would trust the electronic display ahead of the mechanical display.

[SLY33]

are you weary of letting it rev to 8000 for reasons of unnecessary engine wear and tear/failure, or because its not power productive to rev it so high?

the stock rev limit is 8000 or so?

I ask as i used to take mine up to 8000 quite frequently, and then a valve guide broke.. related?!

[Sklyn]

Mine is rev limited at 7000 stock.

my two speedo's used to match up almost perfect. Then after power loss (don't know why, but stereo & TT lost all memory) I could not calibrate the TT which is what leads me to believe that it is wrong?? The power loss has happened twice in 12 months, the first time it calibrated fine, the second just won't work. Any help?

as for bigger wheels, get lower profile tyres and they remain the same size. if u do go bigger i think it is just a minor adjustment to correct the speedo. (just what I was told at the tyre shop a few yrs ago)

[Adz2332]

are you weary of letting it rev to 8000 for reasons of unnecessary engine wear and tear/failure, or because its not power productive to rev it so high?

the stock rev limit is 8000 or so?

I ask as i used to take mine up to 8000 quite frequently, and then a valve guide broke.. related?!

i only keep it below that cos of unnecessary engine wear ... but thats just me... i dunno might be safe?

[ULOOOK]

Computer for sure

I have a digital shift light that runs off my dash and it is identical to the power fc, yet the tacho in the dash is 600rpm higher.

[GTScotT]

my dash is out aswell, using a consult (group buy lcd consult thing) shows my rpm lower than the dash, yet the same as my automotive multimeter. there old cars now, as stated above the mechanicals in them wear out.

[swanny180]

Same with mine.

RPM and speed read lower on my AVCR than on my dash.

Because the AVCR is digitally displaying an electronic signal, it can't really be wrong unless a sensor is giving an innacurate reading (in which case both will be affected)