ECU Remap

Strider590

Hintza wrote: »

Can you guys give me the pro and cons

Well here's one "con".....

Many cheap remaps do things the "easy" way, they simply adjust the ignition advance curve and to stop errors they remove the signal from the knock sensor.

This is BAD, because pre-ingition will trash your engine within 500 miles.

I know someone who worked for Bentley (the factory, not a dealership), a customer bought a car, sent it to some tuning company who remapped it for an extra 200bhp, 2 months later the customer sends it back (on a trailer) bellowing out black smoke and making the sorts of noises that no engine should ever make, expecting it to be fixed under warranty.
Investigations showed that the remap had disconnected the knock sensor and this had basically lunched the pistons.

A good ECU remap is no problem at all, done right it can be better than the original (which was mapped to meet EU regs), but a bad one is just asking for trouble.

JustinR1979

forgotmyname wrote: »

Ive compared the MK3 2L petrol Mondeo against the MK3 2L diesel.

142bhp (190Nm) for the petrol, 130bhp (330Nm) for the diesel. Off the line the petrol has the edge then as the diesel turbo spools up it shoots into the lead but more gearchanges are required to keep it there until the petrol car comes past again.

Mid range overtake the diesel is the choice, But limited revs and the petrol is still going in the same gear.

Swings and Roundabouts.

This is like my old Passat tdi compared to the 1.8t petrol, 130bhp against 150bhp, but 230lb/ft of torque against 130lb/ft.
Normal driving and nipping round 1 car it has the grunt, and does 50+ mpg. You rarely drive flat out, so will go with the torque and mpg

mcpitman

JustinR1979 wrote: »

Obviously depends on circumstances, but flat out the bhp wins through every time

Not true, torque wins races, bhp sells cars.

mcpitman

Had my Vec-C remapped from 120bhp-150bhp, gained 5% on mpg and much more driveable. This did almost 70k miles in this state before it became uneconomical to keep running.

Now in another car, remapped from 160 to 212bhp, the torque increase was phenomenal.

Live mapped with before and after dyno runs. (which in my opinion is the best way to do these changes).

Declared to insurance with rear privacy glass all in for £39 p/a increase.

Main reason fro remap was fuel economy, the power (to me) is an added bonus. At 35k commuting miles per year the remap cost paid for itself within months.

Many modern diesels have dual mass flywheels that need to be treated with some mechanical sympathy. Treat these with care and you will be fine.

DPF has been fine, due to remap giving a cleaner burn and not simply overfuelling the car like most "tuning boxes" do. Car currently does a re-gen every 1k miles (or once a week)

mcpitman

P.s. to the OP...

I believe the wizrdry that is performed delivers a torque curve lower down the rev range, so in short same torque, less revs, less fuel.

NB - there are many if's but's and maybe's to the above statement but this is essentially what I understand.

JustinR1979

mcpitman wrote: »

Not true, torque wins races, bhp sells cars.

Which is not true, even if you are quoting the great Carroll Shelby.


McLaren F1 for example.


Take my previous post of my tdi againt the 1.8t petrol.
I have nearly twice as much torque, and 20bhp less. I would lose the race.


A more accurate saying is "You drive torque, you talk bhp"

forgotmyname

mcpitman wrote: »

P.s. to the OP...

I believe the wizrdry that is performed delivers a torque curve lower down the rev range, so in short same torque, less revs, less fuel.

NB - there are many if's but's and maybe's to the above statement but this is essentially what I understand.

Not quite.

At a given speed the gearing is identical. So 40mph in 4th gear maybe 2000rpm. Say you need 20% throttle usage to maintain that speed on a level road.

Up the torque at that rev range and you can keep the same speed with less throttle usage. Unless you change the gearing the revs will always be the same in a fixed gear.

In my car 4th gear at 40mph uses LESS fuel then 40mph in 5th gear. Because there isnt quite enough torque in 5th so i am actually pushing the throttle down further to maintain speed.

9% throttle in 4th where the torque is plentiful and 18% in 5th where its not quite enough. And yes it also injects more fuel its not just % numbers for pedal position.

Gloomendoom

mcpitman wrote: »

Not true, torque wins races, bhp sells cars.

I'm not convinced by this. In low 1st, my old Land Rover has torque by the bucketful.

I can't see it winning many races though.

BeenThroughItAll

Gloomendoom wrote: »

I'm not convinced by this. In low 1st, my old Land Rover has torque by the bucketful.

I can't see it winning many races though.

Low range or high has nothing to do with it though. With the right gearing (or wrong, depending on your POV) you could have eleventy-million NM of torque and never win a thing

Gloomendoom

BeenThroughItAll wrote: »

Low range or high has nothing to do with it though. With the right gearing (or wrong, depending on your POV) you could have eleventy-million NM of torque and never win a thing

Didn't I just say that?