alistair

Put your car on a rolling road is the only real way to tell.

Try

paulc_percival

What revs is the MY99 Impreza Turbo supposed to rev to before losing power?

I have just got my car back from it's 1000 mile service and after putting in a few tanks of Shell SUL, I thought I would see what the car could do. My car goes up to about 7200 before it experiences the loss of power, it does this in 1st, 2nd and 3rd gear, 4th gear would lose me my licence at those revs!!

For a quick 0-60 time, what is supposed to be the optimum revs for gear changing?

What do other people's MY99 standard Impreza's do?

GaryC

i've got MY99, with Prodrive Performance Pack, which may make things different, but as standard car peak power is c6200rpm there is no real point taking it much beyond that. With mine having so much mid-range torque no real difference taking above 6000 as acceleration is as startling from 4000 up!

Scottie

Funny you should ask - I was going to post something similar myself.

My MY99 is just run in (and getting faster all the time ) and I had read threads saying noticable tail off in power over about 6,200 revs.

I thought this would be more noticable in MY99 cars which have, i think, smaller turbo?

Mine's been run on super plus since new and revs like a demon to 7,000 in 1,2,3 with no noticable power drop off at all.

Maybe its the fuel?

Lee

When r-roaded, my MY99 starts to tail off after 6500. It doesnt drop off though, just a tail off so I guess you could take it to 7K.

MarkL

Hold on there just a second! The original poster said, "My car goes up to about 7200 before it experiences the loss of power". This should be no surprise to anyone, and it should also be no surprise that this happens in all gears because you are hitting the rev-limiter!

When my car was younger I could feel the power start to fade away as you climbed up into the 6k+ range. Now the miles have added up a bit and the engine has loosened up more it revs quite freely to the limiter.

Common thinking on what revs to change at is that it should be around the peak power point, as your power is just going to drop off from then onwards in that gear. In reality the optimimum revs to up-change in each gear is the point at which the torque at the wheels at that speed is exceeded by the torque at the wheels in the gear you want to change to; or the rev-limiter, whichever comes first. In practice if you analyse the torque curves at the wheels in each gear I suspect you will find that you can get the best acceleration by revving right to the limiter in each gear. Obviously hitting the limiter is not much help though, so you need to change a little before that happens.

sunilp

Had my UK MY99 on the PE rollers last weekend. Its peak power of 242BHP (standard spec) is generated at 6380rpm.

Happy redlining!

Paul Wilson

Surely to get max acceleration you want to take the revs beyond max power (sic).
If you look at a power or torque curve, then work out how many revs you drop when you change gear, say 2500. The point to change is the point that gives you the most area under the graph for your 2500 revs.

Tough to put in words but all becomes clear if you look at a graph.