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Discussion Starter · #1 ·
How does VAG COM measure torque. In block 20 of the ECU there is a torque value which changes depending on the load. Is there a load sensor or something?

BTW my chipped 115 PD Bora measures 172 bhp @ 4137 rpm and 272 lb/ft @ 2373 rpm using this method. How accurate is it ?

Jamie
 

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Have you tried doing the dyno plot Jamie? I'm going to do it this w/e if I've the time.

The only other way to check if these figs are accurate would be a good rolling road.
 

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Discussion Starter · #3 ·
Yes I've done the dyno plot using vag com and Excel.

I haven't got std figures for my car only chipped ones.

I have tried a standard 130 pd golf and this showed 256 lb/ft and 154 bhp so it may be slightly optimistic.

I performed the tests in 4th gear. Don't know if it matters but the higher the gear, the longer the run takes and the more samples you get making the graph smoother.
 

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So can you actually plot your Bhp and torque figures? How do you do it exactly? I understand that VAG COM can create a .csv file that excel imports.

Cheers,

Trevor
 

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Discussion Starter · #13 ·
I think it's easier to use the one linked from the vag com site as TDI Lover has said as this uses the torque figure supplied through the diagnostic port and shown on Vag com. The other spreadsheet tries to calculate the figure based on acceleration v mass.

However the older car's don't supply this torque figure so you would have no choice.

TDI Lover - I live in Pencoed. Was up your way today LOL.
 

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Had a quick test with block 20 today and got the following:

In 3rd gear:

154 bhp @ 3906 rpm

251 lb/ft @ 1890 rpm

This proves alot more than the RR i have had done which showed 142, whats anyone think. I know shes quick but that quick?
 

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On the real road you get proper airflow, unlike being strapped down on a rolling road....

Usually you get the more "real world" figures on the real road.

I have heard of PD130's doign 145-148bhp on a RR so you could well have a good one.

Bill
 

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Okay, I've been out doing a few test with 'block 20' and I found it not to be accurate in the slightest.

I had my car on the rollers at 3.5k, and it hit 172bhp with 300lbs/ft, so I have a figure to base my block 20 findings on.

I did an initial 3rd gear run with tuning box connected, and I got back 152bhp with 255lbs/ft, which I was a little disappointed with. So, did a few more runs, and they all got the same figure (roughly)

So, I disconnected my tuning box to see what figures it does as standard - I got the same figures.

I suppose the tuning box is connected post-ECU, but so will any other performance enhancing parts - exhaust, air filter etc.

I dont know how it would re-act with a chip, but I can firmly say that with a tuning box block 20 isnt an accurate measurement.

Tom
 

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Cheers Bill, thats what I wondered after it proved quite good on the RR, but as they only had one fan.....heat soak badly affected the chipped 18ts. I will have a try with your version when time permits.

Tom, as you are not sure about block 20, the torque figs, have you logged the others and done the andy smith version or bills (above)??? shoulndt this give you your 'box figs, think this is how foxy plotted his. I will try this when I get time, doesnt it seem strange that everyone is getting 152-154..
 

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quote:

Originally posted by Ricardo

Cheers Bill, thats what I wondered after it proved quite good on the RR, but as they only had one fan.....heat soak badly affected the chipped 18ts. I will have a try with your version when time permits.

Tom, as you are not sure about block 20, the torque figs, have you logged the others and done the andy smith version or bills (above)??? shoulndt this give you your 'box figs, think this is how foxy plotted his. I will try this when I get time, doesnt it seem strange that everyone is getting 152-154..
I've done the block 20, which is what bill used, except that he has a little bit in the excel sheet to convert Nm to lb/ft, and from lb/ft and revs calculate bhp.

I reckon the 152/154 figure is what the engine thinks it is trying to produce, or what it is aiming for.

Tom
 

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If you have a tuning box, VAG-COM datalogging out of the ECU is'nt going to be right I don't think.

The Bosch ECU is calculating torque output based on standard settings.. The Tuning box is altering these output settings, but the factory ecu does'nt know this. the torque is derived from a whole bunch of tables in the factory Bosch ecu, but with something else in the system, these results are'nt likely to be accurate.

A remap of the same car, should give datalog torque outputs which should be accurate as the factory ecu is 100% controlling the engine...

Thats my theory on it anyway.. [:p]

Bill
 
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