Tuning a Diesel Engine with a plug in box

Delivery_Driver

For an older TD car I'd just use a tuning box, for something newer I'd have a reflash of the ecu/remap.

TheSaint_2

Thanks for the replies. I think i will leave it as the cost of the box or rolling road plus the cost of the insurance hike would counteract any saving i would get from fuel.

I just don't do enough miles to justify it anymore.

It has been interesting reading up on all this though - and looking at the arguments for and against on both sides.

Thanks

motorguy

fivetide wrote: »

Well you'd be wrong but there you go.

I spent hours with the mapper, checking engine response, power, fuelling and emissions in all gears and under different loads to ensure it was 100% safe and matched to the engine.

Of course, why not take two minutes to consider none of these things and simply plug a box in and hope for the best with no idea (as is clear from the number of different 'facts' in thsi thread) what it is actually doing.

Please do explain how it makes the car more dangerous for other road users though, I'm keen the hear that one.

5t.

Well you havent yet mentioned upgrading the brakes, suspension, etc to deal with this massive hike in power?

So yes, you'd be endangering yourself with underpowered brakes, and also the general public with a braking set up not designed to cope with the power.

Also, theres no way the standard engine is able to deal with that massive hike without reducing reliability, so expect something to go bang at some point - hopefully when you're NOT performing some overtaking maneuvre.

My wifes WRX-S has the official ProDrive performance pack and even with a lowly 265BHP the brakes fade under duress and with 12K miles on them are now being upgraded to something heavier duty.

But of course, you know all this already and have actually rally spec brakes on yours and upgraded suspension, etc, etc as this is the internet

motorguy

Delivery_Driver wrote: »

For an older TD car I'd just use a tuning box, for something newer I'd have a reflash of the ecu/remap.

+1

Would work for me

Lum

For an old TD surely a washer in the fuel pump is the best way to go

almillar

I'll chip in for fivetide to Paul - how does a more powerful engine mean that more powerful brakes are needed to stop the car from 70mph? It hasn't got any heavier...

Lum

The issue is that you will now be reaching 70mph in situations where you otherwise would not be able to.

This doesn't apply on straight 70mph dual carriageways, but I can think of many roads locally where an imbalance between acceleration and braking could get a bad driver into a lot more trouble than they would manage previously.

(FWIW, I just have a few bolt on upgrades, exhaust, filter and soon a boost controller. I also have the brake calliper/pads/disk/master cylinder from an R33 Skyline, 20mm wider tyres and Eagle F1 GSD3s all round, so I think I'm pretty well balanced even when I do finally do the ECU)

fivetide

pgilc1 wrote: »

Well you havent yet mentioned upgrading the brakes, suspension, etc to deal with this massive hike in power?

So yes, you'd be endangering yourself with underpowered brakes, and also the general public with a braking set up not designed to cope with the power.

Also, theres no way the standard engine is able to deal with that massive hike without reducing reliability, so expect something to go bang at some point - hopefully when you're NOT performing some overtaking maneuvre.

My wifes WRX-S has the official ProDrive performance pack and even with a lowly 265BHP the brakes fade under duress and with 12K miles on them are now being upgraded to something heavier duty.

But of course, you know all this already and have actually rally spec brakes on yours and upgraded suspension, etc, etc as this is the internet

I don't have the car anymore so no I won't claim all those things. However, two things:

1. No i didn't mention them but you assumed I didn't have them and criticised on that basis. You should never assume things, especially not if you are going to try and take some sort of moral high ground.

2. If you read further on in the thread, my reply ti lum I think it was, I explained an awful lot of this for you already. No the suspension didn't need an upgrade. I put winter tyres on it though when the weather got cold and as said, I did up the brakes, have the calipers refurbed etc so they were operating at their best.

almillar is spot on with what he says re the car being heavier. And while I accept the poitn lum is making abotu getting into trouble quicker it again assumes the driver doesn't know what they are doing. Luckily for me, I do and I would not push the car on an unfamiliar road. As much as you can get into trouble quickly, you can also avoid it. Again, see earlier post for point about overtaking.

Finally, on these cars the differences between the WRX and STI versions are not huge bar the power output so the chassis is rated to carry much more power even as standard. In terms of percentage to the STI power the increase is much smaller, again with better fuel efficiency to boot (I actually had a switchable map put in with a low and high boost setting).

So in summary:

Don't assume things about people you do not know

Read the thread properly before trying to be smart as a result of aforementioned assumptions.

cheers,

5t.

Edit for lum. In the scooby we are talking fractions of a second difference, no more. round a track it would all add up but on a UK road surface the ability to be at the bend earlier is much less of a concern. Using the full power when the surface isn't good would be more tricky.

motorguy

almillar wrote: »

I'll chip in for fivetide to Paul - how does a more powerful engine mean that more powerful brakes are needed to stop the car from 70mph? It hasn't got any heavier...

Extra power when used = extra braking required to slow it down. Extra braking = extra heat in brakes + extra wear. Extra heat = less ability on standard brakes.

motorguy

fivetide wrote: »

Don't assume things about people you do not know

Read the thread properly before trying to be smart as a result of aforementioned assumptions.

cheers,

5t.

Firstly, you are missing my point. You came on here about how really great a remap was and how it was so tuned to your car as to prevent any risk. This is nonsense. That level of power increase simple puts extra stress on already stressed parts - turbos, intercoolers, cooling systems, cranks, etc, etc - No matter how long the remapper strings the process out and tells you its 'optimised' for your car.

Therefore to be trying as you were to take some moral high ground that a £500 in this case is better is simply WRONG.

A simple - but proven - tuning box on a diesel car (as per the O/P's) is an easy and effective way to get an extra 20-30BHP and for a fraction of the cost.

As predicted, all of a sudden, your car had uprated brakes etc - its surprising that you didnt in your original post factor in the £500 or so necessary to upgrade 'standard' brakes to a higher standard? Thats makes your £1000 start to look totally out of perspective to a £90 tuning box.

If brakes and suspension on a WRX are not of any interest then that a standard WRX has much lesser brakes than the 300BHP STi then? Or very different suspension setup?