89 auto revving too high? Part 2
 

Guys,

Done some research and here is how a stock brand new late auto 944 should behave
If from a standing start with your foot all the way down but not as far as the Kick down

0 to 80 KHP first gear up to a max of aprox 5.5 K RPM

Then Up-shift to second dropping the RPM to aprox 3.5 K

80 to 145 KHP second gear to a max of aprox 5.8K RPM

Then Up shift to Third dropping the RPM to aprox 4.2 K RPM

145 to a theoretical 240 KPH at 6.5 K RPM where the fuel supply should get cut by the limiter..

So from an RPM point of view it should look something like this.

2.5 --> 5.5 -->3.5 -->5.8 -->4.2 -->6.5

It sounds like my gearbox is actually acting pretty much correctly, if we factor age and environmental factors I will take it for a spin tomorrow and report what the exact number are when I drive at various speeds.

I will also check the RPM’s at 80 KPH, the assumption is that it should run trough the gears hitting about 5.5 ,dropping to 3.5 in second and if 3rd kicks dropping to 3K or so.


Regards,

Guillaume

Took it out for a spin and here is what i found

60 KPH 3K
100 KPH 3K
140 KPH 4K
180 KPH 5.1K
200 KPH 6K
220 KPH 6.5 K

as you can see it starts to move at 180 5.1K rather than 5K
then 200 is at 6K should be 5.5 K
then 220 is at 6.5 should be 6.1 K

Adding into the mix the fact that the speedo is prob 20 KPH out

Seems like the car is revving at about 1K to hard top speed.

But then for a 13 year old car, i guess that aint too bad.

G.

60/100 kph/ is 36/60 mph and 3k for both. somethings wrong. other turns are pretty close to what you should be seeing.

a silly question but have you checked with another tach as you may have a tach problem.

Kind of assumed that 60 kph at 3K was the auto box in second and that 100 at 3K was the box in third.

how would i check the tach ? any ideas ...
G.

that would be info that you hadn't mentioned.

check turns with a separate tach with cables long enough to close under the hood and still reach inside the car and compare the readings.

i've had my car since may and haven't done what i described because i haven't questioned the turns/speed relationship.

on my older volvo, bosch ignition system, 1 of the 2 wires on the tach went to one side of the coil and don't know where it is in the p-car and the other to ground.

i'm not even sure if any of the above info is valid for the p-car. suggest you check with a competent mechanic as i'm pretty sure there is some way to check accuracy of the tach.

good luckSmileWavy