12 years old VW T32 174 ps with 148000 miles on the clock
I thought it was time to see what the old girl could achieve so booked it in to Pendle Performance for some attention .

Why did I not do this years ago I cannot believe the difference in drive-ability.
while it was not lacking in power and pulled like a train and the last tank of fuel gave me 33.89 mpg of varied running .

I am being gentle in first and second gears ( as drive shafts were suspect on these vans ) but third and forth the difference is amazing from 1200 revs it just goes overtaking is a dream .
and in sixth I am only touching the throttle at 60 mph .

be interesting to see what mpg this next tank of fuel gets or should I wait while the novelty wears off and record the next fill up

very happy

Is Mr Pendle chap still off his head on steroids and banning customers from seeing him work on their van?

😯

10% power gain….i would have thought noticable but not going to transform your overtaking and making progress life. Even with a potentially smoother and wider uasabke rev range, are you sure there’s not a bit of confirmation bias going on?

Not sure on the steroids but was not allowed in the dyno room and was told to have a walk round and come back in a couple of hours .

there is not a lot to see in barlick on a sat afternoon .

not sure I wanted to see as I could hear it revving hard on the dyno as I walked back

Possibly Plumslikesrocks but the Torque gain is very noticeable

Never mind the headline numbers; can we see the graphs?

Every diesel I’ve had remapped has improved fuel consumption afterwards, I think its because of the increased torque & wider spread that means you don’t have to change gear as often.

How much more is your insurance costing though, I bet it’s more than the mpg improvement?

Every diesel I’ve had remapped has improved fuel consumption afterwards, I think its because of the increased torque & wider spread that means you don’t have to change gear as often.

You get better economy as they switch the EGR off. The EGR reduces NOx emissions but gives a fuel economy penalty.

I got my old T5 remapped from 130 to 170 bhp and started using posh diesel, all made a great difference and yes better economy too. Current T6 seems more sluggish in comparison but as it’s still under warranty will wait till after until getting done I guess.

[/quote]redstripe – Member
I got my old T5 remapped from 130 to 170 bhp and started using posh diesel, all made a great difference and yes better economy too. Current T6 seems more sluggish in comparison but as it’s still under warranty will wait till after until getting done I guess

What T6 you got?
Just ordered myself one too.

You get better economy as they switch the EGR off. The EGR reduces NOx emissions but gives a fuel economy penalty.

While this can be done it is in no way standard practice when you get a diesel remapped, the reason you often get better economy is due to a greater spread of torque due to changes of boost, fuelling and adaptions to how the dsg gearbox (if fitted) changes gear throughout the rev range.

Had my 2013 1.6tdi cadddy remapped by falkland performance in Fife, from 101 hp to 148 hp and 246 nm to 315 nm, made a world of difference.

FunkyDunc – Member
How much more is your insurance costing though, I bet it’s more than the mpg improvement?

Insurance stayed the same for me when I had my Golf 4 GTI remapped from 150 to 212bhp.

Mandog – 140 DSG T6 (not the later 150 Adblue one)

If simply tweaking the ECU gets you better driveability and economy why don’t the manufacturers just change their map? What’s the downside of getting a remap aside from maybe higher insurance, is there a reliability hit?

Manufacturers often leave some headroom so they can sell different power outputs whilst using an almost identical engine.

Jeez there’s a lot of bull on this thread!

Funny how lots of STWs are up in arms about VW cheating on their emissions tests but have no issues remapping their own cars, which is extremely likely to result in massive tailpipe emissions excesses……. #doublestandrds

(and btw “only just touching the throttle to do 60mph” simply means the pedal map has been shifted down, as it takes EXACTLY the same amount of power as before to do 60mph……..)

Funny how lots of STWs are up in arms about VW cheating on their emissions tests but have no issues remapping their own cars, which is extremely likely to result in massive tailpipe emissions excesses……. #doublestandrds

That’s what I thought.

(and btw “only just touching the throttle to do 60mph” simply means the pedal map has been shifted down, as it takes EXACTLY the same amount of power as before to do 60mph……..)

I realise you know a lot more about this than me but surely, if the engine produces the required power at lower revolutions, then you don’t to press the throttle as far?

A well thought out map is not just designed to increase peak power output, as most people don’t drive around on the red line.. it should increase the responsiveness and torque too in the lower and middle of the rev range, which results in a much more lively feel, with peak power being a secondary consideration.

tailpipe emissions excesses……. #doublestandrds

It’ll either pass the MOT emissions or it won’t.

Wasn’t the VW thing to con people into thinking the car was greener than it really was?

It’ll either pass the MOT emissions or it won’t

I don’t think there’s an emission standard for diesels, it’s just “no visible smoke” AFAIK. Given the invisible nasties they pump out smoke’s the least of our worries.

Manufacturers have to map engines generically and take account of a massive spread of how they think the customers will drive the car and what fuel they use etc. They have no control over these things so have to assume some customers will put crappy fuel in, and they also have to make trade off’s around emissions vs. fuel economy, vs. performance vs. reliability. Aftermarket mapping companies just make different compromises than the OEM so better economy and performance at the expense of emissions and reliability for example.

and btw “only just touching the throttle to do 60mph” simply means the pedal map has been shifted down, as it takes EXACTLY the same amount of power as before to do 60mph……..)
I realise you know a lot more about this than me but surely, if the engine produces the required power at lower revolutions, then you don’t to press the throttle as far?

Not necessarily. You can change the boost map to achieve higher boost at lower RPM. This will give the impression of more power at lower RPM (and indeed produce more power at lower RPM) but at the expense of turbo reliability, emissions, fuel economy etc. again – all about where you decide to make the trade-off’s and compromises. The OEM’s have to take a more conservative position.

When manufacturers are deciding on their maps they take cars all over the world – to high altitudes in the mountains, sub zero temperatures in the arctic, deserts, all manner of environments and conditions, use crappy fuel, and just basically abuse the hell out of the engine, simulate all these conditions in test rigs to accurately measure fuel economy and emissions. They have to settle on a map that manages all of those conditions. I’m not so sure aftermarket mapping companies are quite so diligent in their testing of their maps, but then again many of us will never take our cars to such extremes of environment so not so much of an issue for plodding up and down the A38. You can’t get something for nothing – if you gain in some areas, you lose in others – that is just a simple fact.

Indeed.

A good example.. Back in my boy racer days, I had a fiesta with a 1700 puma engine in it.

Those engines had a torque limiter which would limit torque in 1st gear, possibly to allow them to use cheaper drive shafts and so you didn’t give the clutch such a hard time, whatever the specific reason for this, the end game was better reliability and longevity of some components.

A simple bypass switch on the dashboard to disable it at will, I think it basically just a simple short circuit somewhere on the ECU, and boom! It pulled like a train on steroids from a standing start.

Required decent tyres and a light touch on the throttle though otherwise it would just wheelspin like hell and you’d red line it before you knew it.

I love it how people spout on about how “manufacturers” map their cars. Well here’s the crack, i’ve spent the last 30 years doing exactly that! There’s a good chance that quite a lot of people on this thread actually drive a car with ‘my’ map in it! So, please, don’t tell me the old “manufacturers leave loads of headroom” or “they map for the worst fuels” rubbish. Back in 1993, yes, maybe, in the last 10 years er,nope.

Lets discuss the 60mph thing. the original van will do 60mph in top gear, so the remapped one can’t downspeed its engine any further. (unless you are also putting the drive ratio up too, which you ain’t with a map)

The engine speed at 60mph before the map, is EXACTLY the same as the engine speed at 60mph after the map. And the power requirement is also exactly the same (unless you’ve somehow reduced the vans CdA as well). So if it’s now doing 60mph with “less throttle pedal” then as i said, the pedal map has just been changed…

And lets talk about making torque at low rpm. Being a diesel, the engine is attempting to run lean (excess air ) at all times. The OEMs have thing like smoke limits and NOx limits, in fact, both of those have their own limiting maps, and these maps are the first to get chopped by the aftermarket tuners.

Without a turbo change, you can’t get more air in at any given speed, so the only way to make more torque is to add more fuel.

About 5 years ago i was asked (as i run a company that consults on this sort of thing) to run a mapped car over the official drive cycle by a well known tuner (who shall remain nameless). 23 sec into the 22min drive cycle i pulled the plug and stopped the the test, because the mapped car was already 10x over the Particulate Limit…..

So, there are NO FREE LUNCHES in engine tuning these days, and as no aftermarket tuner i’ve ever met or heard of runs there cars over the official cycles, then i’m willing to bet my reputation that just about any mapped diesel car will be something like 10 to 100x more polluting than a std one.

I’m just interested – is it considered accurate?

I mean, from the graphs is seems your 12 yr old engine was producing a little more than rated when new, before the remap???

All dyno’s have slight variations in their method of calculating power due to changes in atmospheric pressure, air temperature, under bonnet temperature, engine temperature, tyre pressures, method of securing/strapping car down for power run and there’s also the human variation to take into account. It’s practically impossible to compare one dyno run to another unless you have a suitably skilled operator tweaking the map as he runs through – not all dyno operators are skilled, some are just button pushers akin to painting by numbers, Comparing separate dyno runs is ok for a rough comparison but not 100% accurate.

It’s not uncommon for engines to produce more power when they are loosened up over a few years so to speak, saying that you have to factor in what sort of treatment and servicing schedule the vehicle has had, a poorly treated low milage engine ragged from cold and constant stop/starts will have excessive bore wear and will perform poorly in a cylinder leak down test where as the same vehicle treated with a degree of mechanical sympathy but a high mileage (such as my 3yr old caddy – 110,000miles) will perform admiringly well.

Maxtorque

Very interesting thank you. I’ve a Vw t4 and they are always making a big fuss about potential remapping power gains. It drives quite nicely despite a flat spot around 2000rpm. I was considering a remap for power plus investigating the flat spot, but will leave power where it is (102bhp) and see how it goes. Unless you specifically recommend somebody in Exeter.

2000rpm = 60mph, my preferred cruising speed, which is irritating

Well the good news regarding an old T4 is that it’s probably so dirty as std that remapping isn’t going to dirty it up that much…… 😆

It’s also worth noting there are also some rather esoteric low rpm limits that could be in place to protect things like DMFs / DPFs etc! Voiding those without realising it could land you with a very large bills (especially on a 150kmile engine……..)

@maxtorque does the extra particulate thing mean an MOT fail?

Unfortunately no

Mot doesn’t test for particulates

That seems a bit odd, isn’t road tax calculated on co2 emmisions? Or is that different from particulates? Apologies if these are numpty questions.

I had this big bastard mapped by Pendle (bloke needs psychological help but we’ve done that and he knows his tuning onions):

Ended up 340nm and pulled like a TRAIN. Fully loaded it went past a 180bhp T5 on that hill out of Lyme Regis, both flat to the floor in 3rd. It really was incredible for a 3tonne bus. But hell it kicked out some crap when you pushed the throttle. Literally like those rolling coal videos on the net.

Yes, you can get a lot more power but you will absolutely smash the emissions you were getting before.
I’m a changed man, haven’t even bypassed the EGR on my Hilux now, must be the only one left in the UK with one in place.

johnners – Member

If simply tweaking the ECU gets you better driveability and economy why don’t the manufacturers just change their map?

Some tuning is for really specific reasons. And yes some of it is test defeats- my bike had timing retards built in to give it better results in the driveby noise tests some territories have. Others less obvious- my cad has something (don’t know the actual method) inflicted on it to soften the power delivery at low revs and make it easier to drive off the line without spinning up- it was really wooly at low revs, getting rid of that just made it feel much nicer. (it has an obnoxious amount of torque, no clever diff and no traction control so I can see why they did it, but it wasn’t nice)

The MOT test for diesels (and for petrols too tbh) is really pointless and out of date. A modern common rail diesel does not put in any fuel when just reving in neutral, well , only enough to accelerate the engine to the rpm you are asking for, so they run very very lean (think 150:1 or leaner!) so tailpipe emissions are pretty much un-measurable unless something is really broken. (The test was designed to check mechanically injected dervs)

MOT limits are way way way higher than the certification limits. For Gasoline all it does is check the engine is idling somewhere around Lambda 1 and without excessive hydrocarbons (ie no excessive misfire or missing catalyst) For diesel it only really checks for completely buggered injectors or a catastrophic sensor/ecu issue, ie bad enough to chuck out visible smoke.

The only person I know who has his cars remapped also tends to blow up engines. I’m happy with the performance of my Seat Alhambra as it is and hopefully it runs for many more miles.

The only person I know who has his cars remapped also tends to blow up engines.

Well. That’s conclusive.

..and yes CO2 (for tax) which warms up the planet is diifferent than local pollutants (particles Nox etc) which gives folk cancer and heart disease .

‘chipping’ a car is much like overclocking a PC.

You change a lot of the settings to whatever you choose.

As above the manufacturer sets the ECU to whatever is best for the average consumer to avoid warranty claims.

It’s not rocket science.