Can some one clear me up on diesel engines.

[Carlvtr88]

Can some one explain to me why diesel engines respond so Well to mapping., Or chips is it ? Cause i remember reading some where that you Can get stupid power out of a 206 diesel easily or something. My question is why dont people get a diesel and do this, rather than spending lots of a petrol engine. Aside from the fact maybe one does not like diesels. Also, is it all diesel cars you Can do this to, or just certain ones. Thanks.

[Ashleyp]

Diesels have the torque low down in the rev range, pretty boring if you're into fast driving.

The same reason VTR's are boring ;)

[Carlvtr88]

Diesels have the torque low down in the rev range, pretty boring if you're into fast driving.

The same reason VTR's are boring ;)

so your saying the Extra power from the mapping on a diesel is useless in Reality ?

[TomT]

The turbo helps lol.

But diesels drive very different to petrol engines, as ashley said they're quite boring.

You don't get to rev as high, the power's delivered in a different way etc.

[Giraffe]

Other reason they are boring is that the revs on them usually stop around 4.5 - 5k, and really after like 3.5k you'll be lucky if it feels any different power wise. Just feels flat. I also thought remaps and chips were only really decent on common rail diesels as well, might be wrong though. I don't know why that is either.

EDIT: Hannah beat me to it!

[TomT]

The torque at low range and not revving so high etc is all to do with the much higher compression rates I believe

Fuels also delivered different in a tdi which I guess is why they remap better then petrol engines.

[Carlvtr88]

i suppose What I'm asking is would a higher model 206 diesel mapped, be quicker than a standard 206 gti ? poor example but i just wondered to myself. My friend has a Mercedes diesel and to me it feels quick still. I'm thinking if you were to re map it What sort of gain would you get.

[TomT]

My friend has a Mercedes diesel and to me it feels quick still. I'm thinking if you were to re map it What sort of gain would you get.

What Mercedes? A quick google should find you the answer though, places like r-tech that do remaps usually put up a list of cars and the gains expected from a stage 1 map.

But in answer to your 206 question, no I don't think so.

[Ashleyp]

so your saying the Extra power from the mapping on a diesel is useless in Reality ?

Not useless at all.

Can get some really good power gains from them, but the high revving petrol engines will be more 'fun' (personal preference).

don't quote me as i'm not sure, but the fact diesels are turbo probs is why they map well, petrol turbo engines can respond well to a map too. you can take the R26 to 290bhp and over 300ftlbs of torque with an exhast & map alone (the engines 237bhp and around 220lbsft of torque standard iirc)

i suppose What I'm asking is would a higher model 206 diesel mapped, be quicker than a standard 206 gti ? poor example but i just wondered to myself. My friend has a Mercedes diesel and to me it feels quick still. I'm thinking if you were to re map it What sort of gain would you get.

even the c220 mercs are pretty nippy in diesel form for heavy cars.

[makaveli144]

I have a remapped diesel Alfa GT.

Stock is 150 bhp 225lb-ft
Mine is 190bhp 300lb-ft

Is it quicker than standard, yes, is it quicker than the petrol equivalent...yes.

However it still sounds like a tractor on startup and puffs black smoke when nailing it.

[Monkgti]

most reason it works well on a diesel is the turbo the same reason it works well on a turbo petrol engine, because the map increases fuel and more importantly boost aswell which makes a big difference, where on an N/A car theres no boost to increase!!

[Lewis1600]

Someone on here has a 206 hdi which is mapped, he can answer all your questions to the 206 related.

However, I have a Ibiza TDI, which was 130bhp standard, now its mapped Im guessing near the 150bhp mark.. not saying it is. but most probs.

Like said a diesel will only rev to about 4.5k -5k and at that revs it wont have much go in it. Diesels are best from 1.5k - 3-4k. So It does get a bit boring. But the low down torque in each gear with the turbo feels good lol.

And on the motorway in 5th, foot down and it just goes nicely.

But I wouldnt bother mapping a N/A diesel. Its all due to turbo really.

[rey]

Diesel's dont use spark plugs, just compressed air and fuel.

I imagine by increasing each factor through a remap is why the larger gains are had, probably set up as standard to fairly safe levels.

[Jungle]

Because they have a turbo, same as mapping a petrol turbo engine gets better gains than an NA petrol engine.

[Jay_]

no smoke, no poke ;)

[stevo67]

Can some one explain to me why diesel engines respond so Well to mapping., Or chips is it ? Cause i remember reading some where that you Can get stupid power out of a 206 diesel easily or something. My question is why dont people get a diesel and do this, rather than spending lots of a petrol engine. Aside from the fact maybe one does not like diesels. Also, is it all diesel cars you Can do this to, or just certain ones. Thanks.

Not all diesels simply because they don`t all have an ecu mate.:drink:

[Jungle]

Not all diesels simply because they don`t all have an ecu mate.:drink:

WHAT?????

[timmythechef]

I had 64bhp and 77lb/ft extra when I had my A3 remapped.

[ajdsaxo]

I had 64bhp and 77lb/ft extra when I had my A3 remapped.

Basically a 1.1's power extra for circa £200 - not too shabby!

[Aly]

Someone on here has a 206 hdi which is mapped, he can answer all your questions to the 206 related.

However, I have a Ibiza TDI, which was 130bhp standard, now its mapped Im guessing near the 150bhp mark.. not saying it is. but most probs.

Like said a diesel will only rev to about 4.5k -5k and at that revs it wont have much go in it. Diesels are best from 1.5k - 3-4k. So It does get a bit boring. But the low down torque in each gear with the turbo feels good lol.

And on the motorway in 5th, foot down and it just goes nicely.

But I wouldnt bother mapping a N/A diesel. Its all due to turbo really.

haha is this me?
My 206 HDI has a stage 1 map, never had it rolling roaded but it's roughly 120bhp and 185lb/ft torque, it doesn't set the world alight but goes very nicely, the pull in 3rd is very impressive but as many people have said in this thread it runs out of steam at about 3,500rpm.

I floor it from 1700 and change gear at 3,700 and the revs fall back into that band, once you learn how to drive a diesel you can get the best out of it, it never feels slow when overtaking but I think there are better diesels out there.

Have a look on TDOCUK there's a guy on there with a 306 HDI with a GT25 has 220bhp and 380lb/ft torque and it has a turbo flutter when he changes gear, to build one to that spec costs roughly £3,500 and when you consider you can get similar performance or better for the same price from a Saxo I think people would rather stick with a Saxo or a 106.

Thing people don't often realise is HDI's and most diesels have a lot of sensors, more than petrols and many go wrong.

[Carlvtr88]

right ok. Good reading all your informative replies. Thanks for the input. I Cant remember What Merc my friend has. Its not a top range one. Its a lower down spec. But still the bigger car not one of the proper mini Mercs.

[Carl-h]

Are diesels not setup pretty lean from the factory for emissions? So a map changing the fueling and most importantly the boost gives big gains? You get big gains from many turbo cars through a map though. It's because the boost is turned up.

I might be wrong but doesn't diesel have a pretty slow burn rate? Which is why they're not designed to rev high? Like even diesel race cars (le man ones) rev pretty low and that's race diesel? I do know diesel only light ls under compression so putting some on the floor and dropping a match does nothing lol.

[TomT]

I might be wrong but doesn't diesel have a pretty slow burn rate? Which is why they're not designed to rev high? Like even diesel race cars (le man ones) rev pretty low and that's race diesel? I do know diesel only light ls under compression so putting some on the floor and dropping a match does nothing lol.

Yeah that's right

[Jazz]

In terms of tuning, to cut a long story short nearly all modern diesels have a turbocharger. Remap any turbo car and you're looking at good gains.

As mentioned diesels have that slow burn rate and lower rpm. Lots of low down torque and they become less efficient at higher revs.

Many modern diesels are also mapped very conservatively from factory (mapped for economy as opposed to power) so their engines have plenty more to give.

However, an equivalent petrol turbo is still going to be better for performance.

Quick peek on a repetable tuner's website can confirm this:

From AMD technik-

Stage 1 remap

Audi A3 2.0TDI 140- extra 45bhp, 53lb fts,

Audi A3 2.0 Turbo petrol- extra 60bhp, 78lb ft.

Clear differnence in favour of petrol.

Another one.

BMW 335d- extra 47bhp, 88lb ft torque

BMW 335i- extra 45-50bhp, 81-94lb ft.

Give both engines a turbocharger and it balances the odds. A diesel will get that nice big lump of torque because of how the engine works, but thats about it.

They still stink, they still fart black smoke and they still sound like agricultural misfits.

[timmythechef]

Basically a 1.1's power extra for circa £200 - not too shabby!

Was £175, but that was mates rates, didnt charge me labour, other wise its £399

[timmythechef]

In terms of tuning, to cut a long story short nearly all modern diesels have a turbocharger. Remap any turbo car and you're looking at good gains.

As mentioned diesels have that slow burn rate and lower rpm. Lots of low down torque and they become less efficient at higher revs.

Many modern diesels are also mapped very conservatively from factory (mapped for economy as opposed to power) so their engines have plenty more to give.

However, an equivalent petrol turbo is still going to be better for performance.

Quick peek on a repetable tuner's website can confirm this:

From AMD technik-

Stage 1 remap

Audi A3 2.0TDI 140- extra 45bhp, 53lb fts,

Audi A3 2.0 Turbo petrol- extra 60bhp, 78lb ft.

Clear differnence in favour of petrol.

Another one.

BMW 335d- extra 47bhp, 88lb ft torque

BMW 335i- extra 45-50bhp, 81-94lb ft.

Give both engines a turbocharger and it balances the odds. A diesel will get that nice big lump of torque because of how the engine works, but thats about it.

They still stink, they still fart black smoke and they still sound like agricultural misfits.

Thats a conservative figure tbh, and also if their giving number what to expect its just a 'Off the Shelf Map' to speak, I had mine done by carbon tuning which dyno'd the car three times on standard power, and averaged 141bhp instead of the 138bhp Audi quote.

Then took the engine data, and send off to HQ, 2 and half hours later my custom map was ready to be installed, dyno'd again and made 205.7bhp, but the torque was up to 314lb/ft.

1700 miles later, the turbo blew to peices, and I wasnt allowed to give it the beans for 500 miles.

[Jazz]

Those may be conservative figures, and yes they are generic chips (AMD like to call them remaps, they are not).

1700 miles later and your turbo blew to pieces? Well that tells a story in itself, idiotic tuners trying to wring every last ounce of power and pushing your turbo way past its limits.

So your remap gave you another 60bhp, and then it blew to pieces? Those figures for a sensible map seem about right then.

[Carl-h]

Petrol engines can see stacks of torque too. The VAG 1.8 20VT with the k04 turbo can see 300 lb ft quite easily. Which coincidently can be enough to bend the rods lmao! But they make it pretty low down and the more you rev the more you get. Downside being you'll be very very lucky to see 30mpg where in the diesels even mapped you should still see 50+. I wanna drive a proper diesel, as most the time I think itd suit me as that's how I drive not really going over 2.5k in my VTR but then I'd miss claiming it every now and then so I'd only want a diesel if I started doing silly motorway miles. For every other use I'd rather a petrol.

[timmythechef]

In fairness I didnt clear the pipes out enough, went I say to peices, I am extending the truth.

They advice you especially with a remapped derv, to give it the beans now and again, to stop the soot build up, I didnt once really, and on closer examination it was the main cause.

I'll be honest, once a tank, usually when It hits between quarter and red line, take her upto her 155mph limit, and in the last 15k have never had a problem.

[Carl-h]

Take your car to 155 once a tank? I wouldn't wanna be your licence haha. I try to give mine a run every week or so but it's just 30-40 seconds WOT on the way back from the gf's when the engines nice and warm :)

[timmythechef]

Yeah, my old mans factory is next door to an abandond runway used in the second world war.

My license is clean.

[Jazz]

You got any other mods apart from re-map?

Since a standard A3 TDi 140 tops out at 130.

Interesting to get another 25mph from just a map lol.

[timmythechef]

Just a twin take, have got a video on my phone if you ever want to come to South Wales to watch it.

[LScottBell]

Got myself a turbo diesel recent and thought about a remap.

After the remap does your mpg stay the same or decrease? Always good to have extra power but if not booting it then i would like my mpg to be good still

[TomT]

Got myself a turbo diesel recent and thought about a remap.

After the remap does your mpg stay the same or decrease? Always good to have extra power but if not booting it then i would like my mpg to be good still

I haven't had mine remapped myself but supposedly if you stay out of boost you'll see a couple mpg extra.

Obviously though when in boost you're going to be putting more fuel in as well so you'll lose some mpg.

[timmythechef]

Totally depends on what map you have, my custom map is so that my turbo doesnt really come in at all until 2250 rpm, but works enough for very little lag, this means as I dont use it if I change at 2k, my MPG went up, average bout 65mpg now.

If the turbo comes in early, you will always be using it so your MPG will go down.

[LScottBell]

Got a 2.0 mg zr

Place near me does remaps for 200 + vat so might drop in and see what they can offer.

Take it your still getting higher bhp if needed? Extra kick but if taking it easy then your getting better economy?

[timmythechef]

Mainly yeah, I must admit the sound of it spooling up at 2250rpm just makes you want to plant it, but I still average 650 miles plus to a tank.

Have got 940 miles once, thats an average of 80MPG, but it was basically all day of motoway driving to the south of france, set basically to 70mph at 1950rpm, it creamed it fairplay.

[Jazz]

Just a twin take, have got a video on my phone if you ever want to come to South Wales to watch it.

If I'm ever down that way I'll be sure to take you up on that offer.

If nothing else it will make some light afternoon entertainment ;)

[timmythechef]

Most deffo, your more than welcome. Glad we cleared that up :homme:

[stevo67]

WHAT?????

An example my Citroen zx never had an ecu,bet theres a few others too.:fcuk:

[yorkie]

i been driving a round in my mum 206cc 1.6tdi and i really seeing what people been saying to me diesel is addictive! i starting to like it better good job i just got a audi tdi lol

me mates got a fabia vrs tuned 320bhp in the late 400torques nothing much can touch it and its fun fun fun all the way

and a mate of his he bought out one eve has a octavea vts at 510bhp!!! thats wild!!

[Carlvtr88]

so if you bought a relatively cheap diesel car with a turbo map it. You gain like stupid horse's. Seems nice to me. Then again do you use more diesel ?

[BertieG]

its never just as easy as just a remap. a friend of mine had his octavia vrs remapped and within a week it blew one of the exhaust gaskets by the turbo