http://kmaisch.customer.netspace.net.au/magna/images/large/muffler_dyno.gif
Red lines = After 2.5" muffler, White lines = Standard Muffler
Solid lines = engine power (kw), Dashed lines = Engine Torque (Nm)

Ok, just wondering why this looks wrong. The power in my owners manual is 124kw at 5000rpm. Mine, however, peaks at 128kw at 3000-4000rpm and drops off to only 100kw or so at 5000rpm. It then quivers up and down through to 6000rpm...

Questions:
1) Why does mine peak so early? Is this a problem?
2) Why does my power drop off considerably after 4000rpm? Is this a problem?
3) Why does my power/torque curve wiggle up and down so much between 5000-6000rpm? Is this a problem (considering my car would never rev this high under normal circumstances).

Has anyone had their V6 TR or TS Dyno'd so that I could compare?

Thanks,
Kim

Muffler restriction. Do you have a straight through unit? I have seen dyno graphs that showed max power being held in the upper RPM ranges with the new muffler fitted.

tek - muffler restriction causing the power to peak early? Or causing the power to drop off suddendly?

The muffler is a straight through 2.5"... other than that I've had the cat converter replaced at one stage with a standard unit, and also the flex pipe replaced.

Fuel delivery problems? I dont know much about magnas but Ive seen this before on other cars. could be fuel?

Look at this page: http://www.fastmagna.com/products/walker/

Are you sure the solid line is your engine power and the dashed is your torque? It looks more like the other way around to me..

Look at this page: http://www.fastmagna.com/products/walker/

Thats the same dyno (my car).

cthulhu: maybe it is the other way around... (dotted line power, solid line torque. Hmm, anyone else know?).

Loafer: it could be fuel, but I'm not really sure where to look. I've had my car checked out before for fuel economy problems, and it all came back "fine" - so I'm not sure. I presume they would have checked fuel pump, fuel pressure regulator, etc. Injectors have been cleaned also. Hmm.

hmmm, i agree with CTHULHU - i think the lines are the other way around - though that torque comes on tap real quick

but yeah - if it were my guess i would say you are not getting the fuel required at the higher RPM

have you upgraded your FPR - after working the airflow - you will need a bit more fuel to mix with it.

Also maybe try and injector cleaner

Manual

Hmmm so at 5000rpm I only really have 100kw (should be 124kw). And just noticed the key has dotted lines next to kw and solid line next to nm, so your right... solid line is torque.

Is torque coming on so quick a good thing?

Actually... now that I think of it, when I had the car serviced last they said that the spark plugs on it were the wrong sort (damn repco service centre)... so that could have caused problems like this at high revs?

Hmmm so at 5000rpm I only really have 100kw (should be 124kw).

Don't forget the dyno shows power at the wheels not engine power.

So 100kW @ the wheels is very good, since the motor produces 124kW at the fly.

do all dyno's show power at the wheels? This one has "Engine Power" on the key. I wasnt there when it was being done.

Kim

yeah - don't be worried with the 100kw at the wheels - i have 133 at the wheels on a 3.5L TH Manual with quite a few breathing mods, so yeah - the 3.5L puts out a little more factory than the 2nd gens.

Oh - and torque is good to have straight away!! that is what gets you moving!!

Torque is the pulling force!! and yeah - the plugs could affect it - not firing right in the higher RPM

Manual

I have xx3kW(undisclosed) on my 3.5l. I'm quite dissapointed at how much power is robbed by the auto-box... although I'm probably not going to have the gearbox "powered-up" for the pure fact driving on the street would be a right bastard..

I have xx3kW(undisclosed) on my 3.5l. I'm quite dissapointed at how much power is robbed by the auto-box... although I'm probably not going to have the gearbox "powered-up" for the pure fact driving on the street would be a right bastard..

The VR-X's with tiptronic and busted O2 sensors were putting out 108kw - so don't feel too bad - teh Autos are shocking when it comes to getting power out!!

Oh and Kim - normally you can select on the dyno whether you want the power at the engine or the wheels - though the engine is an approximation as they don't actually know the power loss through your gearbox.

Depending on Auto/Manual/FWD/RWD/AWD will determine how much power is lost through the drive train.

Manual

Manual - so its still possible that mine is at the engine? (so shocking kw output in that case)... especaially considering that the key says "Engine Power (kw)"

Kim,

The fluctuations could all be related to your bad fuel economy too.

They may have made a correction factor estimate from the wheels to the engine, so that could be wrong, so you may have more at the motor. I would probably expect the torque to rise quite quickly in an auto, as that is what they are expected to do at the wheels. The car won't move until the torque is high enough, so the sudden rise is probably to be expected.

I am not sure what the loss through an auto is supposed to be. I think the loss for a FWD manual is about 25%, so I would expect the auto to be up to 35-40%? What gear did they do the dyno in? Being an auto would mean that you can't do it in top gear (3rd) as when you accelerate, it would kick back. So the torque curve may have been in 1st at which case it should rise really quick due to the gearbox multiplication.

not sure what gear they did it in... I imagine it probably would have been 1st.

I'll have to get another done elsewhere (while I'm there to oversee it).

Kim

don't feel so bad!!, my mighty 2.6l put out a whopping 54.7 kw on the dyno at auto salon(i was expecting 25kw) and factory is rated @ 112kw :?: :?:

54kW... I bet you copped a fair amount of flack for that... I dont even wanna know mine :cry:

2.6 litres are about 95kws at the flywheel (thats for EFI), the carby'd versions are 85kws or something

The EFI 2.6 has 98kW on ULP, and 102kW on PULP...

or so the owner's manual says :roll:

hmm, auto - sorry - i thought it was manual - the manual FWD's lose approx 20% power through the box - where as the auto loses about 27-30%

So yeah - just to let you know ;)

Manual

yeah - don't be worried with the 100kw at the wheels - i have 133 at the wheels on a 3.5L TH Manual with quite a few breathing mods
Manual

f$%k me! no wonder you are in the 14's down the 1/4 mile! And ripping V8's while you are at it :D

[quote:2a9e4347b0="Manual"]yeah - don't be worried with the 100kw at the wheels - i have 133 at the wheels on a 3.5L TH Manual with quite a few breathing mods
Manual

f$%k me! no wonder you are in the 14's down the 1/4 mile! And ripping V8's while you are at it :D[/quote:2a9e4347b0]

Power on tap with Torque to boot - but I want MORE!! haha

Manual

How much does it cost to put your car on a dyno?????? :?: :?: :?:

Depends where. Mine was only $50 for a before/after (so $25 each run).

Does anyone know if it can hurt a car being put on a Dyno? The reving up to 6000rpm worries me...

i regularly rev mine to 6500 RPM - so i am not worried - but you can tell them how far you wish to have your car revved

but thats what rev limiters are for - if it wasn't intended to rev that far - they wouldn't allow it.

Manual

i regularly rev mine to 6500 RPM - so i am not worried - but you can tell them how far you wish to have your car revved

but thats what rev limiters are for - if it wasn't intended to rev that far - they wouldn't allow it.

Manual

exactly and im prity sure magnas rev limiter is very much under what they think is neccesary to cope with the longevity of the vehicle. in reality if you service you car regularly and keep good oil in your car you should be able to bump that rev limiter up a grand or 2 :) how you would do that is another thing probably either a sensor change to trick it / ecu change :)

ah ok, cool.