Engine Remapping

[Tony Lockhart]

A remap of a normally aspirated engine tends to have much less benefit than on one with forced induction. Getting more horses from an N/A 6 usually requires mechanical changes. Then it's often cheaper to buy something with more power from stock.

Sort of correct.

However, as everyone is more aware now, manufacturers have had to box clever with engine maps over the years. Back when fuel economy and emissions were tested in a lab at the equivalent of a certain speed in a certain gear, the engine map would lean the fuel at that point. There could be more than one point on the engine’s rev band that this would happen. This gave a strange power curve with horrible peaks and troughs. A good remap would smooth these out, with no downsides in real world driving. Also, throttle response from idle could be greatly improved.

Some recent fast Fiestas have even stooped to closing the throttle valve slightly to get through the testing!!! First thing the remappers did when they discovered this was to stop it happening. Hey presto, a much nicer driving experience.

Yes, the manufacturer’s engineers know what they’re doing, but it might not be for the best for drivers.

 

[Tony Lockhart]

That was the only V6 in the line. The C250 was a turbo I4.

You said 250.

 

[Seeker_UK]

You said 250.

Yep. Agreeing with you.

 

[SteveG]

That was the only V6 in the line. The C250 was a turbo I4 2.1l, or was it a 1.8l?

There were two C250 Coupes at the time (it was a 2006), one was a supercharged 2L (I think) and the other was a 2.5L V6, which is what mine was.

Edit: They might both have been badged as C230's - not C250's. This business of the capacity and the badging not matching is very confusing!

 

[Tony Lockhart]

Aaah

 

[Seeker_UK]

There were two C250 Coupes at the time (it was a 2006), one was a supercharged 2L (I think) and the other was a 2.5L V6, which is what mine was.

Edit: They might both have been badged as C230's - not C250's. This business of the capacity and the badging not matching is very confusing!

I've got it - I was thinking C204.

The C203 had two sub 3.0l V6 6s IIRC, the C230, which replaced the 2.3l and then 1.8l 230 Kompressor and then got replaced by the C240. There was a C280 but only a saloon / estate.

I never uinderstood why they binned the twinpulse 230K for the 230 / 240 V6, apart from the smoothness, they were much thirstier.

Edit - IKWYM re badging. The C230 was a 2.5 and the C240 was a 2.6...

 

[-alan-]

I’m getting old lol. The engine sound is great, the popping would embarrass me

Yeah, loud popping on the overrun is a bit chavvy. Having said that my bike does a bit of mild popping but only in full power mode.

Yiz are getting old

My bike is currently running a map with what can perhaps best be described as an 'incipient burble' on the overrun - grumbles and gets ready to pop, but never quite does, just makes enough noise to let you know it's alive and not quite fully tamed yet..

I know it's almost on a par with the Subaru types with the laptops on the bonnet at car meets/track days btw , but the ecu on the Daytona is easily linked to a piece of software on my old laptop which allows you to chop and change maps - and also do fun things like toggle a key to open and close the exup valve in the exhaust, and the breather flap in the inlet manifold. Little amuses the innocent

 

[JTC]

Just had my T5.1 remapped by a Pendle agent from 102 to about 165bhp. Drives much better - smoother pull through the gears - and fuel economy has thus far gone from about 625-650 miles per tank to well over 700. No downsides though they backed off pushing for extra torque on account of it being a converted camper which might therefore ask too much of the gearbox.

 

[-alan-]

^ That is pretty d@mn impressive.

One wonders why the makers released the engine on the original map with such reduced levels of both power and economy ??

 

[martin clark]

Simple things like market segment positioning/benchmarking; drive train longevity /warranty margins, space to grow the segment... as an outsider I'd guess a whole bunch of over-arching Model/ project values etc. 'how much power' is going to be way down the list of priorities.

Doubtless pfm members like Rana and bor could likely spell out in a huge amount of detail.

 

[chiily]

I'm thinking about getting my Tesla M3 "remapped" to squeeze that 0-60 time to 3.7secs

 

[bor]

It's drivetrain durability more than anything else Martin.

The component design is modelled with respect to cooling and combustion, to end up at a performance figure that won't cause metal fatigue over the lifespan of the engine.

This can be cross-referenced to customer driving patterns to build up a risk profile.

Going above what we specify, would not survive an OEM durability test programme.

Naturally, it's up to the owners to decide for themselves if they want to take on the additional risk.

 

[Rana]

It has comfort/sport if yours has 3 it will be a newer model

Do you have the concerns in Sport mode? I have an A6 45 Quattro with DCT and its urban driveability is impaired unless I am in "dynamic" mode. Infinitely better but FC takes a hit.

 

[Rana]

It’s a BMW 520d auto tourer 47k 12 plate, I don’t need more speed but I would like it to be more responsive from the get go, I think it starts in 2nd gear and as you give it more gas it drops down to first and lunges forward, it’s very annoying.

Do you use regular or premium diesel? If it's the former, and this is a long shot, I agree, but you could have somewhat blocked injectors from running low dosed fuel. This impedes fuel flow and requires you to depress the accelerator pedal in search of more adequate fuel flow which in turn could then cause the undesired downshift. Two/three tank-fulls of bp Ultimate or Shell V-Power can help reduce the blockage and, if that is the problem, then remove the need for the engine to swap down a gear. I would not recommend anything else but the bp or Shell premium diesels from what I have seen. Under-researched additives in the form of bottled boosters (from Halfords and independently owned garages) may help initially, but may create other problems.

 

[Seeker_UK]

Do you have the concerns in Sport mode? I have an A6 45 Quattro with DCT and its urban driveability is impaired unless I am in "dynamic" mode. Infinitely better but FC takes a hit.

Dynamic shouldn't affect the fuel consumption; only selecting 'S' on the gears will.

I have my A5 set to 'S' as much as I can as it means there's no stop / start and minimizes the pause from the SMG gearbox moving from standstill.

 

[Rana]

"Dynamic" mode does in my car as the throttle response and gear shift patterns are adjusted to give a sportier feel.

 

[Seeker_UK]

"Dynamic" mode does in my car as the throttle response and gear shift patterns are adjusted to give a sportier feel.

That must have been introduced after my car was made.

 

[Mullardman]

Sort of correct.

However, as everyone is more aware now, manufacturers have had to box clever with engine maps over the years. Back when fuel economy and emissions were tested in a lab at the equivalent of a certain speed in a certain gear, the engine map would lean the fuel at that point. There could be more than one point on the engine’s rev band that this would happen. This gave a strange power curve with horrible peaks and troughs. A good remap would smooth these out, with no downsides in real world driving. Also, throttle response from idle could be greatly improved.

Some recent fast Fiestas have even stooped to closing the throttle valve slightly to get through the testing!!! First thing the remappers did when they discovered this was to stop it happening. Hey presto, a much nicer driving experience.

Yes, the manufacturer’s engineers know what they’re doing, but it might not be for the best for drivers.

Thanks. This and a few earlier posts have answered the questions which were popping up in my little brain. I wonder if my innocent looking Type S could be turned into a fire breathing monster with a remap?

 

[Tony Lockhart]

I wonder if my innocent looking Type S could be turned into a fire breathing monster with a remap?

Maybe. If you add nitrous oxide. And some fire.

 

[Mullardman]

I think I'd rather just breathe the N2O and pretend I'm really fast.....