as modern diesels tend to be common rail, and have efi?, by uploading a different map to the diesel ecu, would this have any effect?

I understand the air brought into the engine is compressed, and then the diesel is fired in, but what if the air remains the same and more diesel is fired in? or does it not work like that?

 

there will just be more unburned diesel in the exhaust

you up the fuelling and the boost to create more power

most powerful diesel's are unit injection (VW, audi's etc) nowadays though, as it produces more power then common rail, but is noisier

ie: focus tdci is common rail - 115bhp (1.8)
golf 1.9 tdi's can be had up to 150bhp (1.9)

the golf is unit injection but is noiser than common rail systems

i'm a diesel engine test engineer BTW

 

so these people who go around flashing the ecu, unless they adjust the boost, nothings going to happen?

 

Adding more fuel to a diseasel combustion cycle WILL increase the torque that cycle generates. The limiting factor is smoke emissions as teh more we add, the cloudier the emissions become, and the boost is largely used to dilute the fuel and lower the emissions output. On a modern TD theres not usually any need to increase the boost to more than 18psi from the 15 they normally run. (most cases)

When we map a diesel, the boost is controlled from within the ecu, as it is in almost all cars, petrol and diseasel from 1991. get with teh times people... bleed valves / fiddling with wastegates etc died over 15years ago...

 

but the ecu controls the boost

chucking more fuel in will give you more torque, but more smoke and emissions etc, more boost + more fuel = more power

 

Stu @ M Developments

says the guy with a boost controller

 

Only cos i have an antique pre 91 designed ecu...

 

i seen a electronic actuator the other day,, and i cant remember what it was on

 

cheers guys

 

I thought what half of these ECU Mapping people claim that you get a better mpg aswel or is that just a claim?

Claimed:
(Golf GTTDI 150BHP goes up to 180bhp + 10% better fuel economy)

 

No. We actually give you a money back guarantee that you will enjoy improved fuel economy.

 

So in Fairness - Better BHP and MPG who can argue - Does this compromise the lifespane on the Engine/Turbo?

 

Like i told an American i once knew, Diesels will be the cars to own.

would be have any of it? no.. typical..

 

Is there any sort of differences for Diesel fuel then or is that just a silly question. Cos i'll sure i see some Diesel ultimate in BP a few weeks ago?

As for taking over - maybe - but that will depend on the speed restrictions in the future.

 

As POland has turned into kind of diesl tuning paradise last couple of years (diesl's popularity, cheap disel fuel over here) we have quite a lot of them on streetracing scene. 1.9 TDI from VAG wih 300bhp are not unheard of.

 

Would love to see a 300bhp 1.9tdi's Spec and what the costs are

 

I'm not very much into both streetracing and diesles but from memory:


large FMIC (and I mean huuuge), bigger turbo, some upgrades to fuel system, most probably rebuild and reinforced bottomend, machined head, custom manifolds, 3'' free flow exhaust


Of course it smokes like coal powered locomotive!

 

Lol - Would that pass the UK Emissions test?

 

I think it would fail even before entering MOT station.


Dunno how the test is arranged - probably it can have other map for such occasion.

It;s completly different here. Officially my Stg1 Escos is completly illegal here, but it has never acctually been to MOT station. (Well it has been - for headlights set-up ). I bet gap between law and actuall world in UK is much smaller.

 

But 200bhp out of a 1.9 tdi isn't impossible over here with pretty much standard car, i know of a lad with a 130bhp 1.9, ecu has been remapped, air filter, full stainless exhaust and i *think* a large FMIC which is just over 200bhp.

 

Which would be still just avarage result for normally aspirated petrol engine

 

the ford 115ps TDCI engine will do 150ps just like the golf

Unit injectors are no more powerful the CR.

The limits are the engines themselves!

For example the head of the Lynx (the 115ps TDCI engine) is one of the main limitions once you push the cylinder pressures right up. It bascially can not deal with the thermal loads. If you make the very same head out of CGI it can!!

The 2.0,2.2, 2.4 Puma engines (ford 2litre 15v 4 cyl diesel) can take much more power if you redesign the head with a supporting post right above the combustion chamber to stop it flexing and hence cracking.

Alex

 

Are you sure about that "15V"? Tha must be peculiar head design

 

LOL you mean its not got 15 valves?

lol

Alex

 

So it has 3 on one pot?

 

I have a seat Ibiza Cupra TDi with nothing other than a remap, and its making 190bhp, and 330lb/ft of torque (the important figure with diesels)

This cost me Ł500, and I could quite easily go up to 230bhp without a huge amount of cash.

As for emissions, diesels dont get checked for emissions on an MOT in the same way a petrol car does.

The good thing as well is, I pay Ł110 for a years tax.

Bad bit is, 15months and 50k miles later, I'm on my 4th set of 205/40/17s at Ł200 a go, second clutch (warranty), second set of headlights (warranty) and a few other warranty repairs.

I assume Volkswagen Audi wont have all the same issues but clutch and tyres will definitely be there

 

Actually from VAG group Volkswagen hes worst opinion and worst long milige test's results.

From what I've heard best value for money are Skodas.

 

As someone else said, it's the torque that matters, iirc a 200bhp vw tdi is about 400nm of torque from about 1500revs.

 

It's torque....but ON WHEELS that matters. To omit talking about gear ratios we talk about engine power. power = torque x revs!


Petrol engine with 200bhp will have more torque on wheels in it's powerband then 190bhp dieel engine in it's powerband. Also diesl engine's powerband is smaller. Only advantage of diesels is fuel economy.


Now it was N/A vs turbo diesel. COmpare it to tubo-petrol engine... and diesels are worthless in terms of performance. Only upside is that they are cheap to run.

 

sorry i cant agree with that

diesel engines do produce more torque, within their power bands than a NA engine, its just the engines speeds are limited.

as for the only advantage of diesel being economy you only have to look at the new twincharger golf set up.

40mpg, 170bhp and only a 1.4

in the real world my mate struggles to get 40mpg with his tuned skoda diesel and that has 170bhp

 

oh yes they are

EUI's are far superior to any CR system.

now EUI common rail systems, are the future......and i can see one just 15 feet from where i am sitting

 

And engine speed is what makes power. Once more 200Nm@2000rpm is MUCH less then 200Nm@4000rpm.

Good cyclist will make 300Nm@20rpm

It's very new and we only know official tests. Officially Escos burns something like 9 liters per 100km's in real world up to twice as much.

You know any real data for that new VAG engine? I don't.


Also remember that EURO 5 emissions norm for petrol engines is far more stricter then anything that diesels have to cope with!

 

diesel emissions are very strict too though

we could extract so much more power from our truck engines here, if we didnt have to think about euro 4 or 5

 

I am averaging 50mpg in my 190bhp diesel.

I agree with most of what said above though. I can keep up with a Civic type R to around 100 then he'll pull away quite easily. He doesnt have more torque and only a smidgeon more power but he has much better gearing. The ibiza is helped by the 6 speed box but not enough to be a straight line contender.

The TDi Cupra is 160bhp standard and the petrol Cupra is 180bhp standard. It has been proved time and again that over a 1/4 mile there is virtually nothing in it, mainly it comes down to the launch.

But on the road, a diesel will have it from 20-80mph rolling start, and a petrol will have it in almost any other condition.

As previously stated though, I can have the power, torque and still get 50mpg. And I like the fact that I can comfortably overtake almost anything without stirring through the gears

People compare petrol and diesel cars all the time, and there is no real comparison. Diesel cars do what they do well, petrol cars do what they do well. There is a place for both, and neither should replace the other.

 

diesels have a smog test - put too much smoke out at MOT time and its a trip to failure city for you

 

Sure but still they are much easier then petrol requirements. Petrol engines made it to 100bhp per liter in N/A engine 15 years ago or so and never moved forward since. Why?

 

cos all the big money, and research goes into diesels

thats what pays my wages anyways

 

trying not to disagree with everything on this thread........but i dont agree with that as well

i have never seen a diesel run a good quarter mile

my mates struggled to get his skoda Vrs under 16.5 after the re-map. trying over and over again (similar spec to your ibiza)

another 210bhp VRs could only manage 15.7

i bet the cupra petrol could piss that

....or it could be that my mate is a shit driver.....which is prob the case

 

Diesels are very fast on quater miles here. There is english language forum on forum.streetracing.pl if you want to try to ask about the mods and times. I'm sure they run into 13s. But those are crazy things with V10 TDI swapped into smaller cars or Lupo with 1.9 TDI...

 

My Ibiza ran a 15.5 when it was standard. Unfortunately I haven't had a chance to run it since then. And its not really a 1/4mile car so I cldnt care what it runs.

I would generally agree that diesels are crap on the 1/4 (too many gearchanges for one), but if you take a look at Seatcupra.net, there are many videos showing petrol vs diesel and in general they match up reasonably well. two standard cars will be about equal, and two re-mapped cars will be about equal, assuming no other mods.