Performance Diesels

[SJL]

What do people think is the best way of getting the most out of the 320 cdi or any of the cdi's for that matter??

has anyone had any thing done to thiers? , did it make much difference?

 

[Dieselman]

The cheapest way is to have a remap or fit a piggyback tuning box. The best way is to increase the exhaust flow, intercooler capacity, intake flow, then increase fuelling to suit.

Beware the broken gearbox and differential though with any uplift of torque.

 

[SJL]

can you break that down for me a bit ive seen the piggy back from anything around 99p - 399 on ebay etc and im not convinced is a safe option??? might just be my lack of knowledge in this

how do u know what bhp it is to start with as they do 194 / 200 /220 ish i belive?

what power gains are you looking at?

cheers

 

[Dieselman]

Typically 25% torque uplift.

They all do the same thing, that is to raise fuelling by fooling the ECU.

The issue with chip tuning is that it only increases fuelling so raises EGT temps which COULD cause damage if they go too high.
In addition they cause too much torque delivery to the gearbox so shortens it's life.

Lots of people have them fitted but just be aware of the issues.

 

[SJL]

cheers , more power by fooling im not a fan of so thats out , is there any mercedes tuners that do this kind of thing , would they touch a w210
i ve go no issues paying a bit more if its bone properly.

 

[BTB 500]

Also be aware it may affect your insurance (must be declared).

 

[GrahamC230K]

I've heard it said there isn't an MOT requirement for cats on a diesel but I don't know for sure.

 

[Dieselman]

I've heard it said there isn't an MOT requirement for cats on a diesel but I don't know for sure.

True. No requirement.

 

[lynall]

Done all of this on my previous 4 discos from manual pumps to electric pumps to electric unit injectors.

Manual pump was a case of tweaking the inj pump and a larger intercooler plus raised boost prssure, elec pump the same but with a plug in chip (Tunit crap), then got a larger cooler and a proper remap and it was better but not the £900 it cost better! (JJFearn good but not cheap and rubbish workmanship).

Next car got a piggyback chip (by Dastek pretty good altered fueling and the inj timing) then a remap by (TD5Alive pretty good) huge intercooler next which i reckon was worth 5 bhp at most and again not worth the cost, also dropped inlet air temp by approx 20 to 30 degc, but only during normal driving at full bore was the same as with std cooler,exhaust gas temps remained pretty much the same regardless of chip fitted or size of cooler.

Std egt was 650c max and chipped was kissing 900c.

So from my experience i would get a quality piggy back unit, and if you ever sell the car you can e-bay it, with a remap when the car goes so does your money

Also leave the cooler std and the boost pressure, but the egts will still be a lot higher than std.

No matter what unit you buy you will also notice more smoke at night in your rear view mirror which was one of the main things that would put me of doing it again.




Lynall

 

[SJL]

I would deffinatly tell the insurance company , but ive used them many times before and there faily mellow about mods , thankfully!!

so using your expertise where would you go to get your mercs tuned / fettled with

 

[lynall]

Oh yeh and its fueling first on any modern diesel, i have tried the removing cats etc very minor differences.

Boost pressure increases or a larger cooler without any fueling mods will make nothing to very little difference.

Both chip tuning and a full remap will raise the egt that is a fact from the many mods i did all with my trusty egt gauge.



Lynall

 

[SJL]

forgive my stupidity what is egt im thinking exhaust somthing????

 

[BTB 500]

exhaust gas temperature

 

[GrahamC230K]

I'd certainly go for a proper remap rather than a piggy back box that will only fool the car into more fuelling. The trouble is I don't know any recommendable tuners for MB. I suppose you could quiz superchips as to what their remap consists of - ie is boost increased to counter the extra fuelling and what have they got to say re EGTs.

 

[SJL]

so mainly the opinion is got it done properly by a diesel tuner , and find the best medium with power gain --- egt

i belive the bhp is 200 depending on model have no idea how to find out and torque is about 500n/m

and i would roughly expect 240bhp ish and 600n/m torque woulf that be a fair guess???

 

[GrahamC230K]

Doesn't sound unreasonable to me, at a pure estimate.

I'm sure Dieselman could give you a few prudent questions to ask to seperate the real tuners from those who know how to flash an ECU with someone else's code.

I'm by no means technical or mechanical but from what I gather, a diesel must have more fuel to make more power. No other way to do it. However, you don't want to run a diesel engine rich as that would be very bad (unlike petrol), resulting in high EGT, bad for the turbo and your engine internals. The car needs run higher boost and breath more air to use the extra fuel and keep temps down. Something vaguely like that I hope anyway.

 

[login_user]

Brabus d4 tuning box is approved by mercedes they even fit them. a lot of money for something that does the same as a descent tuning box which costs a third of the price

 

[SJL]

any names of tuning boxes / companies so i can do a bit of digging?

 

[Dieselman]

huge intercooler next which i reckon was worth 5 bhp at most and again not worth the cost, also dropped inlet air temp by approx 20 to 30 degc, but only during normal driving at full bore was the same as with std cooler,exhaust gas temps remained pretty much the same regardless of chip fitted or size of cooler.
Std egt was 650c max and chipped was kissing 900c.

Sorry, I don't follow. The EGT stayed the same but went up to an eye watering 900c..that's turbo melting territory, and the intake air went down by 30c, but the same under full chat.

Was that because the intake was drawing more air as a result of more fuel providing more power thus driving th eturbo harder so creating greater boost pressure and air compression.

I like your approach but think you need to concentrate more on flow as opposed to boost. If you can make more air flow into the engine you don't need so much boost, thus temperatures stay lower.

 

[Dieselman]

so mainly the opinion is got it done properly by a diesel tuner , and find the best medium with power gain --- egt

i belive the bhp is 200 depending on model have no idea how to find out and torque is about 500n/m

and i would roughly expect 240bhp ish and 600n/m torque woulf that be a fair guess???

Firstly make sure your car is outputting the standard figures, it's probably not.
Say it's had a drop off of 25%, then the increase from tuning is only bringing it back to standard anyway.