Tuning a Diesel Engine with a plug in box

TheSaint_2

Has anyone bought one of those plug in boxes to improve MPG / BHP on their diesel? I like the claims of 15 - 20% better economy.

I have seen one company doing it for £89, but all the others seem to be 300 - 400.

this is the cheap one: http://www.dynamicdiesels.co.uk/

Anyone got any personal experience on if this works / damages the engine etc?

Thanks!

alx33277

I had my brother's Golf 2.0 GT TDI (140ps) re-mapped at AmD Essex - the increase in bhp/ps is impressive, 197bhp IIRC, but fuel economy has improved by at least 15% Reputable re-mappers will advise on what's sensible to do before you need to start spending £ on uprated mechanicals...

For what it's worth, I wouldnt do a DIY job with a plugin box.. but that's just me.

HTH

Gloomendoom

I've used one. It did nothing for the economy but it did increase the power... and my insurance premium.

Personally, I'd be wary of any company that doesn't have a landline phone number or a contact address.

2sides2everystory

Yes a 15% improvement in fuel economy is, on the face of it, impressive moneysaving at today's fuel prices, but may I ask what was the increase in annual motor insurance premium after making this modification?

alx33277

2sides2everystory wrote: »

Yes a 15% improvement in fuel economy is, on the face of it, impressive moneysaving at today's fuel prices, but may I ask what was the increase in annual motor insurance premium after making this modification?

About £100 extra IIRC - policy brokered by Adrian Flux

Gloomendoom

alx33277 wrote: »

About £100 extra IIRC - policy brokered by Adrian Flux

Same here... although not with Flux as they quoted me silly money.

TheSaint_2

Not sure on the insurance change, I am at very early stages of looking into this - and might not even bother. I have seen other stuff online about using a rolling road to do this mapping instead, and that you can specify what you want from the change. So I would "hope" that if I went down the rolling road route and just specified improve MPG and not BHP i might not have a bump in insurance....

But that is probably wishful thinking

Gloomendoom

TheSaint wrote: »

Not sure on the insurance change, I am at very early stages of looking into this - and might not even bother. I have seen other stuff online about using a rolling road to do this mapping instead, and that you can specify what you want from the change. So I would "hope" that if I went down the rolling road route and just specified improve MPG and not BHP i might not have a bump in insurance....

But that is probably wishful thinking

It is. The only way a remap or a tuning box will improve the mpg is by improving the efficiency of the engine. A by product of that will be a power increase. If you don't use the power you will get more mpg. Unfortunately, an insurance company probably won't take your word for it that you won't use the extra power.

lfc321

(genuine question this): why is it possible to retune engines to make them both more economical and more powerful, as per Alx33277's example? I can understand manufacturer's sacrificing some power for efficiency, or vice versa. But why do they sell cars that can be improved both ways. Do you lose out somewhere else? Reliability??

Gloomendoom

lfc321 wrote: »

(genuine question this): why is it possible to retune engines to make them both more economical and more powerful, as per Alx33277's example? I can understand manufacturer's sacrificing some power for efficiency, or vice versa. But why do they sell cars that can be improved both ways. Do you lose out somewhere else? Reliability??

Reliability is part of it. Meeting emissions targets is another. Some of it is simply down to marketing. Ford, for example, sell versions of the same car with different power outputs from the same engine. The only difference is a software tweek and the sticker price.

forgotmyname

These plug in boxes usually just fool the ecu into thinking the fuel pressure is too low. So the pump works harder
and the injectors work harder.