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Hi guys,

I have some simple (maybe dumb) questions regarding the info that we read from out ECU's.

I've gotten hold of the devices that I need and have now hooked up the laptop to the car so I can log the results, monitor the car for changes and also to compare the results after I made mods on the car to judge if they are helping with performance or not.

For now, I've just logged the results with ECU talk and in a couple of days will try out CalumSult (if it will work with Vista).

Anyways back to the questions:
1) can I assume that the peak RPM that is logged is the true RPM until cut-off?
(the reason for this is the guys here have confirmed that we should have a 7200rpm limit but I've been upto 7600 redline and the ecu also confirms that we get upto 7500/7600 rpm before the limiter kicks activates.

2) speed, how accurate is the speed that is being read? (the car still runs factory spec tires and stock ratio gearbox) When doing testing a few years ago on a dyno, we took it to 180km/h on the speed on 4th gear and the speed on the dyno stated 172 km/h..... according to data I've logged about 2 weeks ago, I took it to 180 (clock speed and when I looked at the results from the ECU, it logged 172 km/h) (*disclaimer, these results were during testing and not street racing*)

3) does the ECU record display speeds in odd numbers? *there's not a single odd number logged anywhere in over 1 hours worth of data)

I have a few other questions but will query it after running the other data logging software.

Any feedback appreciated.

Mervyn
 

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Hey MervynG, very interesting information that you gathered :biggthump

....
1) can I assume that the peak RPM that is logged is the true RPM until cut-off?
(the reason for this is the guys here have confirmed that we should have a 7200rpm limit but I've been upto 7600 redline and the ecu also confirms that we get upto 7500/7600 rpm before the limiter kicks activates.
....
I once was driving on a two lane, different directions road and I had to quickly pass a slower car in front of me (before the dotted line ended and became a double solid line).

I had to down shift and step on the gas, after I passed that person and was already in the correct lane, I was still going and I noticed the car was reaching 7500 rpm, right after that I felt something and right-of-way I realized that 7600 rpm was the fuel cut off mark and up shifted...

I'm afraid of doing that again, I can't see it being healthy to the car, when the engine doesn't get any fuel and just stops.....
 

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SE-R GREEK
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2,581 Posts
Hi guys,

I have some simple (maybe dumb) questions regarding the info that we read from out ECU's.

I've gotten hold of the devices that I need and have now hooked up the laptop to the car so I can log the results, monitor the car for changes and also to compare the results after I made mods on the car to judge if they are helping with performance or not.

For now, I've just logged the results with ECU talk and in a couple of days will try out CalumSult (if it will work with Vista).

Anyways back to the questions:
1) YES. It is as accurate as it gets. You are going up to 7600, no matter what you "should" be going up to.

2) Accuracy close to +5% (what you get) is acceptable for manufacturers. It helps you avoid speeding tickets as well. VERY rarely is erring on the opposite side "allowed", i.e. doing 180 while showing 172.


3) This is a GREAT observation!! Never realized it, will have to check the "formula" in the ecu sometime!
 
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