Could some one confirm whether the speedo on my WRX is a bit inaccurate.
3000 revs in 5th = 76mph
1500 revs in 5th = 44mph
Seems to be reading a bit fast.

Cheers

 

seems about right, mine is about 3500 - 4000 at 80mph (private road of course )

 

how can that be right?
ratio is a constant relationship betyween revs and speed.

some is seriously amiss.

assuming one of your readings is correct,

you should be doing either 38mph at 1500 rpm
or 88mph at 3000 rpm, depending on which one (if either is correct).

My wrx was 20.8 mph per 1000 rpm

 

how can that be right?
ratio is a constant relationship betyween revs and speed.

some is seriously amiss.

assuming one of your readings is correct,

you should be doing either 38mph at 1500 rpm
or 88mph at 3000 rpm, depending on which one (if either is correct).

My wrx was 20.8 mph per 1000 rpm

 

Got to be careful here, guys...

Do all imports have exactly the same gear ratios and final-drive?

Didn't think so...

Lewegie, I think you're going to have to be more specific about model and age of your scoob. So someone can compare like with like.

Regards,
Squizz.

 

Your right Squizz, mines a 94 WRX and i reckon that the higher indicated speeds are reasonably accurate but lower down say near 30mph it seems to be fast.
I'm going back out this afternoon and shall try the 20.8mph per 1000 revs.