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Old 22nd December 2021, 22:14   #21
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Sorry chaps but this is complete rubbish!

One line is power and the other torque!

A standard 131bhp M47R produces 221lbft of torque at 1900RPM. The graph of this remap shows 250lbft at the same RPM. This is an increase of about 13%, not doubling. If this is for a high-end remap, would it be reasonable to assume that an ordinary remap from the same source would produce a 5% to 7% increase?

Things are not appearing as rosy as perhaps is being suggested?

I suspect the 160 remap is not that dissimilar to the one shown here up to around 2200RPM i.e. the rev range for normal most driving.
Go on, please explain how mapping works. You do realise the rover torque peaks at 221lbft? Numbers are always peak numbers. A remap can shift where the peak torque is. Is peak torque at higher than 1900rpm more in the typical rev range that you drive not more useful? You obviously don’t understand how adjusting the maps work, or how map figures are quotes. 131ps, not BHP btw.
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Old 22nd December 2021, 22:34   #22
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Go on, please explain how mapping works. You do realise the rover torque peaks at 221lbft? Numbers are always peak numbers. A remap can shift where the peak torque is. Is peak torque at higher than 1900rpm more in the typical rev range that you drive not more useful? You obviously don’t understand how adjusting the maps work, or how map figures are quotes. 131ps, not BHP btw.

I do understand how mapping works. I agree that 131 is PS not bhp, my mistake in quoting. But where do you get doubling of torque as stated above?

Also, I do understand that the standard M47 engine's torque is a peak of 221lbft. But it peaks at 1900RPM. If you push the peak torque point up in the rev range, the power increases but the torque does not. With a diesel, you drive below 2200RPM most of the time and this is the rev range where torque is most useful in a diesel engine.

I am challenging that claiming a high peak power output is necessarily a good thing in a diesel engine if this is achieved by pushing the peak torque higher up the rev range. It is the torque curve up to around 2200RPM that is really useful in a diesel engined car which is why I assume people who have had the 160 remap find the driveability to be so much improved. As long as this is achieved, the actual vale of peak power is rather irrelevant.
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Old 23rd December 2021, 07:22   #23
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I do understand how mapping works. I agree that 131 is PS not bhp, my mistake in quoting. But where do you get doubling of torque as stated above?

Also, I do understand that the standard M47 engine's torque is a peak of 221lbft. But it peaks at 1900RPM. If you push the peak torque point up in the rev range, the power increases but the torque does not. With a diesel, you drive below 2200RPM most of the time and this is the rev range where torque is most useful in a diesel engine.

I am challenging that claiming a high peak power output is necessarily a good thing in a diesel engine if this is achieved by pushing the peak torque higher up the rev range. It is the torque curve up to around 2200RPM that is really useful in a diesel engined car which is why I assume people who have had the 160 remap find the driveability to be so much improved. As long as this is achieved, the actual vale of peak power is rather irrelevant.
I didn’t say that it doubles the torque output of the stock map? I think you have misread or I misread what Colvert wrote, I read it that he said the torque curve starts low and doubles as you get up the range. Not that the torque on that graph is double a stock map?

Imagine having a stock 116ps map and only having 192lbft of torque, shooting up to 320lbft would be a very dramatic increase.

If peak power is irrelevant then the map on here should be sold as a moderate drivability improvement map, not a “160” map as it isn’t an achievable peak number.
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Old 23rd December 2021, 09:31   #24
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Very illuminating discussion – though, as usual, people who do seem to understand the topic having contradictory different opinions on it. But I’m particularly interested in the claim that the famed club “160” map does not – and perhaps CAN not – produce 160bhp (or ps or whatever we use nowadays).


I had my CDTI (131ps) remapped with the 160 map at a club meet something like 9 or 10 years ago. I’m going to commit sacrilege here, and say that I was very disappointed in the results – driving home, I couldn’t detect any difference at all in the car’s performance. Brim-to-brim fuel consumption tests before and after revealed no difference there either.


I’ve always been very reluctant to post this, as the members involved in producing the map have been extremely helpful to me in the past, and to countless others here over the years. But I’ve always struggled to understand why so many posted that the map had transformed their cars, when it had no measurable effect on mine… I guess, if in reality it’s a struggle to get even close to 150, mine can’t have increased that much from its 131 starting point.


Regarding maps in general, back in 2001 I had a new chip (that’s how you did it in those days) put in my 1988 325i. It was supplied by a notorious West Midlands “chipper” – and, as with the Rover, had no noticeable effect. By chance, my car back then was maintained by a local BMW specialist, who also ran a small E30 Beemer-based racing team.


I asked him about chips – he said, for normally aspirated cars, they were a con, as there was simply no way to boost their power significantly by altering the map. They’d tried every chip on the marketplace in their racing machines, and none provided significant extra power.


In fact, what they did find was that some of the most heavily-promoted ones were mapped to reduce the engine’s power below, say, 3500rpm, then bring it back up to normal again – making the power curve more peaky gave a great illusion of extra power.


Turbocharged cars, he pointed out, were a different story.
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Old 23rd December 2021, 09:59   #25
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Big Russ remapped my Tourer diesel to 160 must be 5+ years ago. Transformed the car. Never had any problems: car now at 149K miles. Far more responsive than my petrol 2.5 V6 which is also in fine fettle.
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Old 23rd December 2021, 10:38   #26
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Originally Posted by Jamiewelch View Post
I didn't say it wouldn't be. Just their number isn't reachable so it is a myth. Imagine how well 320lb/ft of torque would pull a caravan

Dyno printout of a none "160" map below. Producing good power and lots of torque. Unfortuantely it is a proper dyno run with printout

I'll put it the simplest way. If the map is already injecting the maximum amount of fuel before it starts smoking, how can fitting a synergy box produce more power? It injects more fuel, it can't magically create more boost. So the map isn't injecting the maximum fuel before you get smoke. it is injecting significantly less. You start getting smoke when you start pushing more than 150bhp because there isn't enough boost.

No dyno printout = no proof


I cannot say if the 160 remap has given me 160bhp, I may not have put across what I was trying to say very well so I hope this helps. The remap (i wont call it a 160 remap for sake of argument) that I had done via a forum trader has made my car much better for towing and general driving. I am not heavy on the right foot and so dont thrash the engine but the car is a better performing car and 160bhp or dont, I would suggest having a CDT rempped is a worth while thing to do particularly if like me you want to tow with it.

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Old 23rd December 2021, 10:46   #27
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Here's my take on remaps. I will say however that I do not have the 160 remap - I am of the school that if the standard engine configuration is not enough then buy a car with superior performance. For me, the 131 PS (129bhp) tune does all that I need from a Rover 75.

Quoting power (bhp or PS) is not very informative, as a power increase can easily be achieved by moving the ramp part of the torque curve to higher RPM. What is far more important is that the improvement in torque occurs in the RPM region where the engine spend most of its time. For a diesel, that is up to 2500RPM (or 2200RPM for towing) as this equates to 71MPH (62MPH) in 5th gear for our cars. In my view what really matters is how responsive the car feels to the driver. It is this driveability that is most important, not the peak power number.

My comments in this thread were driven by claims that the 160 map providers were telling lies. This is an unnecessary claim and one that is contrary to the experience of a huge number of members who have had the 160 map. Hopefully it is obvious why I don't think its important whether the '160 map' actually leads to a power output of 160bhp (or PS) or not.

In relation to post #23, personally I would consider it poor show to uplift a car's maximum torque from 192lbft to 320lbft for normal road use. This represents an uplift of 67% whereas around 30% is the maximum that I would entertain for normal road use.

If a driver really feels the need for a power increase from 131PS to say more than 150PS, I would suggest that he/she should be looking for a different drivetrain i.e. a different car.

hogweed - sometimes there is a component that limits the engine's performance irrespective of the map. In you case I would have gone back to remapper so that he could diagnose the cause of your performance limitation.

Here are a couple of old threads that people may wish to peruse.

https://the75andztclub.co.uk/forum/s...d.php?t=144735

https://www.the75andztclub.co.uk/for...=Remap+problem

PS I am not a performance shy person - our XF-S benefits from 600Nm of torque at 2000RPM which I quite enjoy!

Last edited by MSS; 23rd December 2021 at 10:49..
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Old 23rd December 2021, 10:48   #28
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Let's make one thing perfectly clear here, we never developed the maps ( yes there's more than one. ) to produce "160" it was developed to improve drivability of the car which as many, many owners who have had it done have testified countless times to be the case.
It only became known as the 160 map after the results that were published on here found by other owners.

Now as you should well know Jamie, you can put the same car on the same Dyno 20 times on the same day with the same settings and get 20 different results.

The Dyno manufacturers themselves state that and that any map that noticeably improves the drivability of the car can be considered to be a good map.

That is what we've provided, at a reasonable cost.

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Old 23rd December 2021, 11:41   #29
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hogweed - sometimes there is a component that limits the engine's performance irrespective of the map. In you case I would have gone back to remapper so that he could diagnose the cause of your performance limitation.

Yeah... but Phil did actually do a T4 session before applying the map, and found everything fine to proceed.


As Russ says, perhaps I was misled by all the people on the forum describing it as "160" - I wasn't aware that this wasn't "official".


Back in the (pre-ECM) day when I used to get my kicks from tuning motorbikes, it was generally accepted that you wouldn't feel less than a 10% power increase... so if mine started with 131, it would have needed an increase of 13 to be noticeable, ie up to 144, which is getting close to what appears to be a 150 limit... I dunno. Doesn't really matter now.


As regards "drivability", responsiveness etc, these things are very subjective. Again, all I can say is that I didn't feel any difference
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Old 23rd December 2021, 13:26   #30
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Let's make one thing perfectly clear here, we never developed the maps ( yes there's more than one. ) to produce "160" it was developed to improve drivability of the car which as many, many owners who have had it done have testified countless times to be the case.
It only became known as the 160 map after the results that were published on here found by other owners.

Now as you should well know Jamie, you can put the same car on the same Dyno 20 times on the same day with the same settings and get 20 different results.

The Dyno manufacturers themselves state that and that any map that noticeably improves the drivability of the car can be considered to be a good map.

That is what we've provided, at a reasonable cost.

Russ
We know about dynos. But, you don't get a huge variance, you don't get a car reading 120-130bhp when it should be running 160!

Also your signature states 160bhp.

Last edited by Jamiewelch; 23rd December 2021 at 13:28..
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