Negative side to Tuning Box?

[shewy]

I am due to pick up my 1.9cdti vectra 150 in a week or so and have been trawling through this site looking at possible mods to do to the engine.

I have noticed that there seems to be a lot of different tuning boxes about by various companies, all of which seem to have their fair share of fans so to speak.

What I want to know is what are the down sides to fitting one of these tuning boxes? Sorry to sound like a pessimist but I find it hard to beleive that I can purchase a box for between £65 and £250, simply plug it in and will get an extra 30bhp with no downside!! Surely if this was the case the manufacturers would fit them as standard.

does it reduce engine lifespan maybe??

Please prove me I'm wrong as I like the idea of an extra 30bhp for just £65 but it just rings alarm bells in my head. The old resistor idea for petrol engines comes to mind for instance!!


Thanks in advance to anyone who can give me any info on how they work etc

[r.bailey63]

Fitted mine nearly a week ago now, so far no negatives to speak of, more power and more mpg, what more do you want

[Caterman]

It does throw the trip computer out by 4 or 5 mpg so the true mpg records will have to be taken from filling up.
The tolerances of the engine is kept within safe limits when a box is fitted.
Irmscher even do a box now that is warranted by Vx. It is the same box that is widely available from many sources but in a different wrapper. If it's good enough for them it's good enough for me.

[garner]

No negitives from me as yet either I have the £65 caterman special fitted to mine. I think that manufacturers don't fit them as standard partly due to the co2 emissions. Some please correct me if i'm wrong though.

garner

[andy d]

I have mine fitted for a week now and no problems whatsoever but as stated, the mpg on the trip computer looks a bit optimistic, I seen to be getting the same mpg but I am having a bit more fun than usual and have been heavy on the throttle.

Once I settle down to normal taking it easy speeds I'm sure the mpg will improve loads.. 1.9 CDTI and getting 530 miles per tank with 195bhp on tap...can't be bad!

[Caterman]

1.9 CDTI and getting 530 miles per tank with 195bhp on tap...can't be bad!

That's what i get so it's all good

[garner]

Mine is also similar did 510 miles and computer said 90miles left in tank.

[AJA]

Fitting any performance part to an engine will effect it long term. It's always a balance between performance and reliability. It's exactly the same as a remap, tuning box, induction kit etc.

[Gsi3.2]

What I want to know is what are the down sides to fitting one of these tuning boxes? Sorry to sound like a pessimist but I find it hard to beleive that I can purchase a box for between £65 and £250, simply plug it in and will get an extra 30bhp with no downside!! Surely if this was the case the manufacturers would fit them as standard.

does it reduce engine lifespan maybe??

Please prove me I'm wrong as I like the idea of an extra 30bhp for just £65 but it just rings alarm bells in my head. The old resistor idea for petrol engines comes to mind for instance!!


Thanks in advance to anyone who can give me any info on how they work etc

right.. they work by fooling the high pressure fuel pump into beleiving that there isn't enough fuel pressure in the common rail, making it run it at a higher pressure, so when the injectors open they dump in much more fuel than normal and more fuel = more power..

Why don't manufacturers tune the engines as standard?.. no 2 engines produce the same power, so they tune them all to a standard, garanteeable power figure, so they work to the lowest HP if you get my drift.. some engines no doubt make more, but if they detune some then it's a easy 'standard figure' to acheive.

this 'tuning down' means that even the lowest performer has plenty of scope within the manufacturers tolerances to have that horsepower figure improved... no engine manufacturer runs their engines at 100% of capacity straight out of the box..think of nearer 70% on turbo engines and you'll be close....normally 80% on normally aspirated ones....

thats why in this case the tuning box ( a basic variable resistor in the case of some of them) can fool the engine into making more power quite cheaply..

yes, it can effect the longterm reliability of your engine if you abuse the car, but improve the servicing schedule and it will negate any of the effects caused by the box...

use the box sensibly and it should have just as long life as without one..but keep it turned right up and cane the car everywhere at your peril.

[wardy]

Surely if this was the case the manufacturers would fit them as standard.

Renault now offer a box on new cars. My previous car was a megane, and I nearly traded it in for a Diesel estate (before I saw the light!) and was offered the option of a Renault tunning box.