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Location:
Brisbane
Registered:
June 2003
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Location:
Perth
Registered:
October 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:41
 
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Haha awesome power curve, Perhaps your 7mge wishes it were a 7mgte, you got some serious turbo lag there 
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I supported Toymods
Location:
Plumpton/sydney
Registered:
November 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:41
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The pics are of your choke not TVIS
P.S that is a cool power curve 
BEN
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Location:
Brisbane
Registered:
June 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:42
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Wilbo, Gumby and my jaws dropped...i was like WTF when it screamed like that 
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I supported Toymods
Location:
Perth
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:44
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There is something majorly wrong with that dude, I said it before and I'll say it again. There is nothing that a 7M does that could make its power jump like that AFTER the curve starts tapering off. It's almost like a vvtL-i with a massive cam change.
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Location:
Perth
Registered:
October 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:45
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April fools was a long time ago, you should be able to rule out the dyno operator playing tricks on you.
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I supported Toymods
Location:
Perth
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:47
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I know, shootout mode should rule out anything weird but:
1) it's making a lot for a 7MGE, even a healthy one
2) it's doing it through an auto
3) there is no explanation for that spike at the end, the power is already tapering off. The TVIS would step in a lot earlier if it was working, and its effect wouldn't be that pronounced.
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I supported Toymods
Location:
Australia
Registered:
November 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:49
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| V8_MA61 wrote on Mon, 06 September 2004 21:37 |
Funny this is, you could actually hear the car rev up nicely, then just SCREAM - obviously thats where that last uber bit of power was...
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Blake, if you look at it, the point where it "jumped" 30-35kW, occured over a 5kph band.
That 5 kph section, would be equivalent to about 300rpm section.
You wouldnt hear the motor change much at 300rpm, unless something let go within the motor that was stuck (like an air passage)
But then the A/F ratio is too smooth to suggest that.
Go get it redone like you should have when he gave you that one
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Location:
Brisbane
Registered:
June 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:49
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but it wasnt tapering off? it stopped creating power for a while then went off...
The car was well warm before the dyno (i was first up, and id driven about 1hr 15 minutes beforehand) so i dont see how choke was relevant?
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I supported Toymods
Location:
Perth
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:51
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Dude, what do you mean it's not tapering off? It plateaus, drops a tad them goes nuts. Tell me what is going to make a 7M do that, and don't say just cos.
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Location:
Brisbane
Registered:
June 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 13:53
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it dropped maybe 1-2kw, and then rose again..i dont see that as tapered off..
I have no idea what caused it, hence my opening of this thread.
If theres something wrong, and im supposed to have more low/mid power, i want it fixed.
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Location:
Brisbane
Registered:
February 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 14:16
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does a 7mge actually have TVIS? my copy of the TSRM:
<www.cygnusx1.net/supra/library/TSRM/>
would suggest that there isn't.
Seeing as your auto got a hit from behind - i'd be considering pointing the finger at it... maybe it's not locking up the t/converter until high rpm/power output?
The low ouput at low-to-mid range rpm could also be easily pointed at the gearbox (slipage).
another possible is that the WoT switch (or switching point) is coming into effect very late in the rpm range - at the point it goes off the scale, you suddenly get richer (e.g. much more petrol)?
wild guess: harmonics in the intake suddenly start workign in your favour?
it might be more useful to map RPM on top of another dyno run
... there any gTech's that could be borrowed in brisbane?
now... if the 18R turbo could make that kind of power i'd be very happy 
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Location:
Brisbane
Registered:
June 2003
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I supported Toymods
Location:
Perth
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 14:23
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Maybe, but if you look at a chart of Ed's or Glen's engines, the variable intake changes over about middle of the rev range, not just before the redline.
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Location:
Brisbane
Registered:
June 2003
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I supported Toymods
Location:
Australia
Registered:
November 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 14:25
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| thechuckster wrote on Mon, 06 September 2004 22:16 |
Seeing as your auto got a hit from behind - i'd be considering pointing the finger at it... maybe it's not locking up the t/converter until high rpm/power output?
another possible is that the WoT switch (or switching point) is coming into effect very late in the rpm range - at the point it goes off the scale, you suddenly get richer (e.g. much more petrol)?
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AFAIK, torque convertors don't lock up under WOT/high power applications, otherwise they get damaged.
And the A/F ratio gets richer at the end coz the throttle is snapped shut, so suddenly there is no air, and it takes the ecu a few millisecs to lean out the mixture
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Location:
Brisbane
Registered:
February 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 14:26
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ahh... you would have "ACIS Air Control Valve"
only works at 60 degrees of throttle opening and must be >4200rpm
easy way to test... disconnect electrical connector on VSV controlling the actuator, then dyno again.
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Location:
Brisbane
Registered:
June 2003
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Location:
Melbourne
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 14:49
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i would say the torque converter unlocked or it droped back a gear.... get a new dyno guy...
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I supported Toymods
Location:
Australia
Registered:
November 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 14:50
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| Allan wrote on Mon, 06 September 2004 22:49 |
i would say the torque converter unlocked or it droped back a gear.... get a new dyno guy...
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unless it was done in drive, which I doubt, there is no way it could have dropped from 2nd to 1st
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Location:
Brisbane
Registered:
June 2003
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Location:
Brisbane
Registered:
June 2003
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I supported Toymods
Location:
Australia
Registered:
November 2003
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 15:26
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| V8_MA61 wrote on Mon, 06 September 2004 23:10 |
so itd seem the figures werent optimistic 
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Yeah, but I bet their dyno's didnt increase 30kW in the last 300rpm
Seriously dude, the dyno operator fucked up somewhere.
There is no other explanation
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Location:
Rocky Mountains, Canada
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 15:29
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[quote title=CrUZsida wrote on Tue, 07 September 2004 00:56]| V8_MA61 wrote on Mon, 06 September 2004 23:10 |
Seriously dude, the dyno operator fucked up somewhere.
There is no other explanation
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Could also be the dyno itself at fault.
The fact that the dyno operator didnt redo the run after that readout suggests to me that he can only be dodgy/lazy.
Any good dyno operator should know that it really isnt possible with your setup.
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Location:
Brisbane
Registered:
June 2003
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Mon, 06 September 2004 22:19
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| V8_MA61 wrote on Tue, 07 September 2004 01:49 |
how do you know it wasnt 1000-1500rpm? this runs out of puff at 6500.
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Look at the speed over which that 30 rwkW "surge" of power occurs over. Power would appear to increase from 86 to 115 over a speed increase of only 4 kilometers per hour. This would equate to at best a few hundred rpm - check for yourself (I'd imagine it was a second gear pull). Also note that the curve does a little loop and then travels 'backwards' to zero. I suspect what your graph demonstrates is some glitch. Your car certainly isn't making 115rwkW - more like 87.
| V8_MA61 wrote on Tue, 07 September 2004 01:49 |
agreed it could be the operator, but how has he fucked up/ what has he done wrong??
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He didn't repeat the run and allowed you to walk away thinking you made 115 rwkW. I would go back and get him to explain the graph to you.
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Location:
South Australia
Registered:
July 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 00:31
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That dyno graph is ghey man! Take it back to the operator and get him to either justify it (the 117kW), or do the run again. Given that the car is an auto and rear wheel drive, 117kW at the wheels is in the range of 175-185kW at the engine. This is not likely for what is essentially a standard 7M-GE.
Do the calculations on how fast that power rises (the 30kW delta over a a few hundred RPM) - and you are talking about something near the range of 600Nm of torque at the crank (only guessing here, cbfed doing a real calculation).
There's definitely something happening either in your transmission or the dyno.
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Location:
Brisbane
Registered:
June 2003
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I supported Toymods
Location:
Perth
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 01:17
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FFS, OVER AND OVER AGAIN YOU TRY THAT!!! You can't relate the figures back to their flywheel power with any great deal of accuracy!!! 
Take it back to the dyno guy and get him to do it properly.
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Location:
Brisbane
Registered:
June 2003
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I supported Toymods
Location:
Perth
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 01:23
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It is helping, there is something seriously wrong with that. If a dyno operator handed me that, and I wanted a re-run, I wouldn't be paying for it.
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Location:
Brisbane
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 01:23
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If it was something wrong with your car, that sudden kick in the power curve would be EXTREMELY obvious. Just like turbo lag, as someone else mentioned. Admittedly I've only been in your car once, but I certainly don't recall it behaving like that at all!
The dyno readout is dodgy, end of story.
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Location:
Brisbane
Registered:
June 2003
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Location:
South Australia
Registered:
July 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 01:59
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| Quote: |
wouldnt it equate to: 115.2 x 1.34 = 154.4kw x 1.34 = 206.8hp = std 7mge power.
thats equating for 1/3 drivetrain loss, which probly isnt out of reach for a heavy assed A340E
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Short answer - no. If you are getting "1/3" drivetrain loss, then your 115.2kW figure would equate to 2/3 of what you would expect to have...thus your figure at the flywheel would be 3/2 of 115.2kW -> 172kW (or thereabouts, using head here)
Having said that, there is no way you can figure out what the actual flywheel kW is from a dyno figure, there are too many factors...in all honesty, if you really were getting 115kW at the wheels, you could be getting anywhere between 155 and 190kW at the flywheel 'depending'.
Lastly, lets say you are gaining 30kW at the wheels in the last little bit of revs like on that graph...that means that at the flywheel (due to your '1/3' losses rule) you are gaining 45kW over that period. Lets roughly say that it occurs over a 500rpm (at the fly) delta.
First convert 45kW to 45000W - then convert 500rpm into 52.36rad/sec
so you get a torque at the crank of (45000/52.3) Nm = 859Nm...AT THE CRANK...
THIS IS CALLED 'BOLLOCKS'. Do you want me to add up the uncertainty in that figure as well, just to prove that there is no way that dyno graph is accurate? Cause I can if you like, but it's going to waste 5 minutes of my life 
Trust me, that graph is wrong...even if your car did suddenly 'open up' -> to get 800ish Nm of torque is an EXTREME change of air flow...I mean, like "adding another 6 cylinders" kind of change in flow.
What is happening here is there is a change in the torque multiplier between the engine and the wheels -> ie gear change.
Or the dyno suddenly broke
Or my maths is wrong Which is kinda likely...feel free to correct me afficionados.
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Location:
South Australia
Registered:
July 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 02:05
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btw - that's the *average* torque over that 500rpm delta...looking at the graph it is not even close to linear so I'd expect a peak torque figure much higher than that. I don't think a standard 7M-GE gets higher than even 300Nm...let alone near 1000Nm.
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I supported Toymods
Location:
Australia
Registered:
November 2003
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 02:10
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| FWDboy wrote on Tue, 07 September 2004 09:59 |
THIS IS CALLED 'BOLLOCKS'
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Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 02:17
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Saw virtually the same thing at the Toyota Nationals Dyno day in Newcastle.
MX73 with 7mgte changed gears when the operator backed off. Graph looked very similiar.
Was kinda funny actually, every guy with a 1j in a cressida breathed a sigh of relief when they found out why his power figure was so much higher.
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Location:
Brisbane
Registered:
June 2003
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 02:19
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ok i give up. i really dont care anymore. And yes i seriously doubt the car'd have 900nm of torque.
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Location:
Brisbane
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 03:52
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You asked for answers and you got them... what are you cracking the sads for?
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I supported Toymods
Location:
Perth
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 04:00
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| Norbie wrote on Tue, 07 September 2004 11:52 |
You asked for answers and you got them... what are you cracking the sads for?
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Gold
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Location:
Lost in the K hole
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 04:11
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| V8_MA61 wrote on Tue, 07 September 2004 11:20 |
my point is i dont want to waste another 1hour driving and $50 to perhaps have the same result/ readout if there is something wrong with the motor that i can fix
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in summary - theres nothing wrong with the motor whatsoever
youre car is making around 90rwkw, has good economy, and if built well, is probably a nice reliable power plant. quit worring about the dyno curve (which is CLEARLY a fuckup).
ed
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Location:
c'town, NSW
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 04:46
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| Allan wrote on Tue, 07 September 2004 00:49 |
i would say the torque converter unlocked or it droped back a gear.... get a new dyno guy...
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listen to allan
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Location:
Perth
Registered:
October 2003
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 04:49
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| V8_MA61 wrote on Tue, 07 September 2004 09:20 |
how do you define accuracy? it isnt going to alter the real power by 30 FWKW!
my point is i dont want to waste another 1hour driving and $50 to perhaps have the same result/ readout if there is something wrong with the motor that i can fix.
isnt this section supposed to be HELP not criticising?
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Dude everyone is helping by saying it is a dyno fuckup, nothing wrong with your car. Also emphasing the only way to be certain of this is to take the car back again.
Im getting sick of all these dyno/vehicle power debates, dynos are teh gey for power output, but excellent for tuning and comparing rear wheel power after mods and between different cars on the same day!!
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Location:
South Australia
Registered:
July 2002
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Re: MA70 dyno and power curve - weiird!
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Tue, 07 September 2004 05:03
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MY MATHS IS SHIT!!!
Just so ya know
I wonder at what point I thought that rate of change in power with respect to rotational velocity had ANYTHING to do with torque.
I solemly declare to wax my nuts with napalm and beg for forgiveness.
The point still stands that the dyno graph is bs though
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Location:
Brisbane
Registered:
May 2002
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Re: MA70 dyno and power curve - weiird!
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Wed, 08 September 2004 13:08
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I was there, can't say that I was paying much attention tho.
If you ask me I have a sneaking suspicion the the auto changed up (because the dyno operator hit the rev limit) pretty sure if you've locked the gearbox in second and you go past the rev limit (autos not having rev cuts to my knowledge), its setup so that it automatically up shifts. This is the only thing that I can think of to account for the (what I referred to on the day, and have to continued to refer to thereafter as a suspect graph, sorry blake, it looks well suspect!) Correct me if I'm wrong on the changing up system.
Cheers
Wilbo
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