Why are remap prices so secretive?

[Bellow]

Closed loop will keep the optimal AFR ratio as the revs are dropping through the table. Just shutting off one or the other will result in massive engine braking which you may want on a race car, but not on a road car.

Cutting fuel only (leaving butterfly open) shouldn't increase engine braking - notice the lack of on diesels but shutting the throttle certainly does. It wouldn't be worse though than pre FBW days but worth avoiding I'd have thought for that reason and others (oil consumption?).

I wonder then the over-run strategy on Phil's FBW K1600. To this point (in time) it has been standard practice for bikes to have the so called 'slipper' clutch release on over-run - frequently under vacuum operation/activation. A FBW set up could obviate the need for that - providing it doesn't mess up the cat.

 

[ToeKnee]

Link Thunder. It's a wire-in ECU, not plug 'n play unfortunately so a lot of work to integrate.

I've used and done a lot of tuning with megasquirt ecu's but wouldn't want to try and splice one into my R231. Thanks for your replies though.

 

[400ixl]

Haven't seen a megasquirt in a few years now. I was using Emerald M3d's around that sort of time.

 

[Deleted member 6183]

As a teenager I drove the mechanic's Mk1 Escort somewhere on an errand. This car was regarded as a bit of a beast and I soon found out why.
The throttle was like a switch, either flat out or off.

Iron butterfly

 

[C36fan]

Having done ODB, custom ECU mapping (including for a manufacturer and race teams) and written my own pretty much from scratch.

For a road car, can you remap and ECU via an ODB port as well as ripping it open and writing it directly to the chip. Well in many cases yes you can, the days of non changing ECU's are long gone. Its usually only where the manufacturer has looked to apply security measures does this become hard or even impossible.

For live mapping, can you do this via an ODB port. Not as much as with a custom ECU, but you can follow the same principle which is what it is about. You can run a data logger that is looking at all of the parameters live and then make adjustments. Rarely even on custom ECU's would you do that whilst the vehicle is still moving. So time is the real difference. Its quicker to change a parameter on a custom map than change and reload a full map, so the process is slower and usually means less tweaking is done. But for a standard car that isn't really an issue.

Custom map developers who modify the pre-defined maps to suit the individual car actually probably do a better job than those who just load a pre-defined map. Provided they know what they are doing of course.

There are those who just buy maps off the internet and throw them on a car with little to no customisation or actual knowledge of what the map is doing are pretty dangerous. Those who have developed base maps and then push them to cars without individualisation (the Brabus, Kleeman etc) are pretty good and will have put a lot of hours in to making it safe, but it won't take into account anything else you have done or the individual car. You then have the likes of GAD etc who have developed a base map and then tweak it for your car.

Basically avoid the first type of internet mappers. Either of the other two will be fine, you will get a more performance manufacturer level from the big boys, but the smaller companies will probably get you more power unique to your car.

As for why they don't advertise pricing, well its a competitive world, they are always adjusting prices per car based on the work they have done, how difficult or easy it is, how long it will take (can be anywhere from 5 minutes to 4 hours to just load a map) and they are reacting to their competitors pricing.

As for why they don't tell you in detail what they do, its hard to put it into layman's terms and you then get threads full of misinformation. So better to not say anything then have the punter just get it all wrong.

can you read that to me ? lol

 

[st13phil]

I wonder then the over-run strategy on Phil's FBW K1600.

Can't say for certain, but my guess is that it still fuels and not just to keep the cats happy, but also the rider. Bikes - even lardy tourers - are a much lower inertia proposition than a car and hence anything less than a perfect transition from closed to open throttle or vice versa would be felt very clearly by the rider.

 

[Alex]

I've used and done a lot of tuning with megasquirt ecu's but wouldn't want to try and splice one into my R231. Thanks for your replies though.

Agree, that would be too drastic. Would be interesting to see what you decide to do. Keep up in the loop.

 

[Bellow]

Can't say for certain, but my guess is that it still fuels and not just to keep the cats happy, but also the rider. Bikes - even lardy tourers - are a much lower inertia proposition than a car and hence anything less than a perfect transition from closed to open throttle or vice versa would be felt very clearly by the rider.

Looking at the specs for said bike as posted by yourself, slipper clutch is a feature. So, I'd guess, that keeping the butterfly closely aligned with the twistgrip is the chosen strategy.
For a car, another reason to shut the throttle on over-run is the need for vacuum for brakes.

Re cats. Can't find it (again) or I'd link it, but I read an article on management strategies for the recently introduced Porsche flat four. Where previously Porsche would have just richened the mixture to compensate for rising IATs, now they finesse the cam timing and rein in throttle opening as maintaining correct conditions for the cat is paramount (the cycling either side of Lambda = 1 a necessity it seems for three way cats). When cats were first introduced and were merely two way, fuel shut off on over-run was still preferred (I think) but nowadays continual fueling as long as some air is getting through to the cat seems to be the norm. Gets very complicated very quickly!

 

[st13phil]

Looking at the specs for said bike as posted by yourself, slipper clutch is a feature.

It does indeed have a totally mechanical slipper clutch that also acts as a pressure multiplier when on the throttle and providing drive, as well as releasing pressure and allowing the clutch to slip when back-torque is applied on the overrun. Here's an explanation:

An important benefit is that it keeps the clutch lever action very light, but I confess that after more than 25 years riding big Hondas with regular multi-plate clutches, it's taking a while to adjust to the relative lack of feedback to the left-hand as the clutch engages when making slow-speed manoeuvres!

BTW, it may have a BMW badge on it, but the engine / transmission were designed for them by Ricardo Engineering

 

[Bellow]

Cheers Phil. And sorry OP for the threadjack!

It does indeed have a totally mechanical slipper clutch that also acts as a pressure multiplier when on the throttle and providing drive, as well as releasing pressure and allowing the clutch to slip when back-torque is applied on the overrun. Here's an explanation:

An important benefit is that it keeps the clutch lever action very light, but I confess that after more than 25 years riding big Hondas with regular multi-plate clutches, it's taking a while to adjust to the relative lack of feedback to the left-hand as the clutch engages when making slow-speed manoeuvres!

The ramps aren't dissimilar to those found on the driven 'clutch' on sled CVTs, similarly deployed to create an axial force (for backshifting in the sled's case). Some (Aprilia, Rotax, more?) use vacuum for the slipper function (but no increased clamping so no respite from higher hand lever force) which kind of makes a mockery of the belief among those who install bike engines in cars that there isn't vacuum for brakes. (Maybe not consistent enough though).

BTW, it may have a BMW badge on it, but the engine / transmission were designed for them by Ricardo Engineering

As much as I have the highest regard for Ricardo I'm still quite surprised to read that. Have the Germans finally rid themselves of NIH syndrome? Will I have to stop telling to anyone in earshot about when Porsche refused Ford's offer of help when both were locked in battle to beat each other in endurance racing?

 

[Bellow]

Found this >> AutoSpeed - Electronic Throttle Control Advances from 2009.
And within it, this:

''An example where ETC performs exceptionally well is where a driver lifts the accelerator pedal quickly. This action usually generates a large hydrocarbon (HC) spike at the tailpipe. However, electronically tailoring the throttle butterfly close rate maintains a more stable combustion process - giving les total emissions. Note that Delphi claim their second-generation ETC system can reduce tailpipe HC and NOx emissions by an average of 15%.''

ETC = Electronic Throttle Control.
So how abruptly the throttle is cut is a feature. Wonder if the thinking is the same 10 years on.