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Discussion Starter · #1 ·
Could somebody please explain the finer points of getting a decent block 120 log to discover a rough esimate of bhp and torque?

Do you drive the car hard? Change gears? Any coasting down involved?
 

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Block 120 is the torque log, so what you want to do is a full throttle run, from lowish revs (somewhere before your turbo comes in) up to as close as the red line as possible, keeping your foot planted all the way. Your best bet would be in 4th gear, so you would get a nice long run through the rev range while accelerating, your rev'ing slower so getting more data logged per second, but your end speed might get you in trouble. You can use 3rd gear, but 2nd is probably too short. You dont need a coast down, but I often dip the clutch for a while so I can identify where the point in the logfile where I 'stopped'. You'll also want as level a bit of road as possible, also as straight as possible cos you'll have the foot planted.

Hope that helps !
 

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Ahhh! So you dont actually need to coast all the way back down then? Its quite unbelievable how long it takes to coast back down from say 60mph!

Will have to have a look again tomorrow.......... im sure that my car has neither block 115 or 120 tho.. odd!
 

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Chris - the coastdown is only for when the car doesnt calculate the torque in the ECU. It calculates the acceleration via the change in speed vs time (logged with VAG-COM), and then with the powers of Excel you tell it the weight of the car, it then uses the length of time it takes to coast back down to calculate the rolling resistance. The coastdown would technically be more correct (if done on a level surface, without wind, and the correct weight of the car taken into account). I never got around to trying the coastdown, so cant really vouch for it.

As you said, I dont think the older ECU's have the the torque block though.
 

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Discussion Starter · #7 ·
Using 4th Gear from around 20mph I gave it everything whilst logging block 120. I then put this information into the spreadsheet that creates a torque and bhp curve.

How accurate are these readings? I got around 210bhp and 250ft/lbs torque. I can live with the torque but 210bhp?

I have a 2003 1.8T 180 DBW with Revo 4 bar software using timing 6 and high boost 9 on the SPS3. I have a full turboback milltek exhaust and dynatwist CAI so I would have thought that 240bhp was more realistic but not sure on the torque.
 

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Maybe there wasn't enough load (possibly the road was slightly downhill?) if that is the case you wouldn't get the correct figures. Have you done a graph and is it possible to log boost at the samee time as torque?
 

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Discussion Starter · #11 ·
Eddy, it was a pretty flat motorway. The car seems to pull very rapildly so im guessing that these figures are slightly out.

I would be interested in your thoughts on my car at Cheshire if you would like a drive?

I did do a graph, I'll get it off my laptop and post it.
 

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I done this very test as part of my University disserstation and done over 70 runs of the block 120 log.

My car always made good torque readings (256lbs/ft) on Highboost but always only made around 207bhp.

When you say the car "pulled" rapidly, that was the torque not HP; just cause the car pulls doesnt mean it has high BHP.

A guy told me last year that "Torque gets you there and Horsepower keeps you there".

Plus, as I remember Bill (Badger) telling me before i started all my tests; Always try and do them on the same road at the the same time of day and if possible in the same weather conditions. This proved very difficult for me as it broke into the summer half way through my experiments. Therefore heat played a big part in hindering my power outputs.

I made up a little programme within Excel using some SQL that automatically takes the log file created by VAG-COM and calculates all the power figures and plots them into a dyno for you.

If anyone wants it give me a shout. Makes things a hole lot easier and quicker.
 
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