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[aaronjb]

I am not a re mapper, but I sat next to a very good one doing my own car. I asked several questions as you do when interested.
He told me that "on road live mapping" was best, also top speed in top gear was not needed to get peak power for the re map... Or words to that effect.

I know when my car was done top speed was not needed, although granted 60-80 was done alot, then had to go through the gears but top speed was not reached.

I arent arguing by the way here just interested in your view   
 

You don't need VMax in top gear no - but you do need to cover all of the peak load cells (at least the ones it's possible to get to) in the map, otherwise it'd be possible (though unlikely) to drive 'off the map' - whether or not you can do that in lower gears depends very much on how tuned the car is..

I can do it in the MR2 in 3rd, but it flies through the map so fast that the software can't log fast enough (12 samples per second, so quite slow - I imagine a Link/MoTeC setup would have better resolution) so I have to use 4th gear.. which means you're going pretty damned fast by the time you've logged 7200rpm

Must admit I was severely disadvantaged doing mind - I was driver and mapper at the same time.. lots of logging, parking, adjusting map, logging, parking, repeat ad infinitum

Better to do it as a team of course - one driving, one listening to a pair of det cans & mapping..

Though I still think a brake dyno is better - if nothing else, you're less likely to lose your license doing it 

(Andy is one of 'the' names in mapping though, so I have no reason to doubt he hit all the required parts of your map & so on.. although whatever ECU it is must log very fast to be doing it in a gear that only hits 80mph!)

[Kevin Wood]

Well, my Westfield has never seen a rolling road. Started off up the road with no map at all and within 30 miles on the road I had it running pretty much perfectly.

Mapping on a rolling road has advantages in that you can hold high speed/load combinations until the engine melts, but mapping on the road gives you the transients that happen in real driving that you can't reproduce easily on the rollers and yes, the engine operating conditions will always be slightly different. That should be compensated by intake air and coolant temperature sensors but, IME, you're often mapping out deficiencies in these too.

IMHO, you can't map a car on the rolling road without at least driving it a few miles to check if it's a dog to drive and iron out the little flat spots and hesitancies. Vice versa, you aren't going to wring every last few horsepower out of it without a rolling road, especially where it comes to tweaking the ignition map where the changes are subtle and difficult to detect with a seat-of-pants dyno.

Having said that, I could have spent a couple of hundred quid getting mine setup and would have been none the wiser as to how it was done. As it is, I spent that money on building a wideband lambda controller and I'm now equipped to tweak it whenever required, and have gained an awful lot of knowledge doing so. Depends whether your desire is for a turn-key working car or to learn and do it yourself.

A wideband lambda sensor is totally essential if you're contemplating this, one you trust to tell you the truth, too, especially with forced induction because it's so easy wreck an engine if it goes lean.

I find you can get the basic map dialled in by watching the lambda sensor and tweaking the map on the fly (helps if someone else is driving, but I didn't have that luxury ). More detailed tuning is best done by processing a data log that includes varied driving. I had a script that processed a datalog into a percentage error for each cell of the map, and then applied it. A couple of iterations of that and you've basically got a car that's indistinguishable from one that's had a half day on the rolling road.

It doesn't really matter if you can't hold it at peak RPM at WOT with this method. As long as you've done it for long enough for the lambda sensor to settle you have the information you need in the log.

I'm not familiar with your engine management. Most of my experience is with the various incarnations of Megasquirt.

Whilst they are all basically the same, one thing you need to be able to do is find your way around the mapping software to make real-time adjustments, so, if you can, find someone who's familiar with your system.

[aaronjb]

(helps if someone else is driving, but I didn't have that luxury ).

That sounds familiar. Don't worry, Kevin, next time you want to tweak the map in the Westfield ... I'll drive!

(Actually the first run out in the MR2 with the turbo fitted saw a friend of mine driving - it's very hard to map when you're pinned against the door flying around a roundabout while he 'keeps up' with an Evo VI  )

[maracus]

(helps if someone else is driving, but I didn't have that luxury ).

That sounds familiar. Don't worry, Kevin, next time you want to tweak the map in the Westfield ... I'll drive!

(Actually the first run out in the MR2 with the turbo fitted saw a friend of mine driving - it's very hard to map when you're pinned against the door flying around a roundabout while he 'keeps up' with an Evo VI  )

Lol sounds a laugh and a half


Ok thanks for ya comments peeps, I have a few people to be trying now so hopefully should get somewhere with it. Also been given a couple of companies to try, A&M conversions and Rs tuning, so hopefully I'll have an interesting update in the next few days...

[aaronjb]

Lol sounds a laugh and a half

It's the only time I've ever felt car sick in my own car  Still there have been many hilarious episodes with Mark and I in the same car - like the time he was trying to convince me to go round the roundabout faster, and I bottled it & went up the A1 sliproad instead of back to his house.. All I heard was "Why did you do that!?" - because I thought we were going to crash into the bridge, that's why! 

[Marks DTM Calib]

The only dyno that will allow an engine to be correctly setup is an engine dyno.

[maracus]

The only dyno that will allow an engine to be correctly setup is an engine dyno.

Fair point, but if I was going to be chasing horses with such degree of precision, I'd be running standalone management and distributorless ignition 

Think a simpler method without calling in the engine removal faries will suffice 

[cem_devecioglu]

I am not a re mapper, but I sat next to a very good one doing my own car. I asked several questions as you do when interested.
He told me that "on road live mapping" was best, also top speed in top gear was not needed to get peak power for the re map... Or words to that effect.

I know when my car was done top speed was not needed, although granted 60-80 was done alot, then had to go through the gears but top speed was not reached.

I arent arguing by the way here just interested in your view   
 

You don't need VMax in top gear no - but you do need to cover all of the peak load cells (at least the ones it's possible to get to) in the map, otherwise it'd be possible (though unlikely) to drive 'off the map' - whether or not you can do that in lower gears depends very much on how tuned the car is..

I can do it in the MR2 in 3rd, but it flies through the map so fast that the software can't log fast enough (12 samples per second, so quite slow - I imagine a Link/MoTeC setup would have better resolution) so I have to use 4th gear.. which means you're going pretty damned fast by the time you've logged 7200rpm

Must admit I was severely disadvantaged doing mind - I was driver and mapper at the same time.. lots of logging, parking, adjusting map, logging, parking, repeat ad infinitum

Better to do it as a team of course - one driving, one listening to a pair of det cans & mapping..

Though I still think a brake dyno is better - if nothing else, you're less likely to lose your license doing it 

(Andy is one of 'the' names in mapping though, so I have no reason to doubt he hit all the required parts of your map & so on.. although whatever ECU it is must log very fast to be doing it in a gear that only hits 80mph!)

I can say you need a faster cpu

generally speaking for here, initial custom mapping done on dyno, then final  corrections on the road :-/

[aaronjb]

I can say you need a faster cpu

Nah - the processor in the ECU is doing far more than 12 calculations per second, and the laptop is capable of much more - but the interface between the two is RS232 at a relatively low speed.. so you can only read so many data points per second (and the ECU insists on pumping out a full frame of data each time of everything it knows about, there's no selective monitoring to have, say, only RPM/load/knock/lambda at a faster rate)..

To be fair it's a pretty inexpensive standalone (Apexi PFC ~£400) compared to the competition (MoTeC, Link XLEM etc) - I think even the newer Megasquirts have eclipsed it in terms of speed, but it's still a default choice for a lot of Japanese cars here, in the US and Japan simply because it's plug-n-play for a huge number of cars (even comes with a default map, usually ripped straight from the stock ECU by Apexi so you can plug in and drive on a stock engine)

[Marks DTM Calib]

The only dyno that will allow an engine to be correctly setup is an engine dyno.

Fair point, but if I was going to be chasing horses with such degree of precision, I'd be running standalone management and distributorless ignition 

Think a simpler method without calling in the engine removal faries will suffice 

Agreed and hence I would say that an on road setup would be close to a rolling road (and to be honest, the results I have seen from rolling roads vary hugely!)

[aaronjb]

The only dyno that will allow an engine to be correctly setup is an engine dyno.

Fair point, but if I was going to be chasing horses with such degree of precision, I'd be running standalone management and distributorless ignition 

Think a simpler method without calling in the engine removal faries will suffice 

Agreed and hence I would say that an on road setup would be close to a rolling road (and to be honest, the results I have seen from rolling roads vary hugely!)

All the skill is in the guy mapping, after all, not where it happens

Though oddly enough an aquaintance of mine has just had a new engine delivered - 7ltr of Ford V8 built and set up on an engine dyno. Mmmm. Torque.

[cem_devecioglu]

p

I can say you need a faster cpu

Nah - the processor in the ECU is doing far more than 12 calculations per second, and the laptop is capable of much more - but the interface between the two is RS232 at a relatively low speed.. so you can only read so myany data points per second (and the ECU insists on pumping out a full frame of data each time of everything it knows about, there's no selective monitoring to have, say, only RPM/load/knock/lambda at a faster rate)..

To be fair it's a pretty inexpensive standalone (Apexi PFC ~£400) compared to the competition (MoTeC, Link XLEM etc) - I think even the newer Megasquirts have eclipsed it in terms of speed, but it's still a default choice for a lot of Japanese cars here, in the US and Japan simply because it's plug-n-play for a huge number of cars (even comes with a default map, usually ripped straight from the stock ECU by Apexi so you can plug in and drive on a stock engine)

under normal conditions rs232 can handle more data flow something wrong there..

[aaronjb]

p

I can say you need a faster cpu

Nah - the processor in the ECU is doing far more than 12 calculations per second, and the laptop is capable of much more - but the interface between the two is RS232 at a relatively low speed.. so you can only read so myany data points per second (and the ECU insists on pumping out a full frame of data each time of everything it knows about, there's no selective monitoring to have, say, only RPM/load/knock/lambda at a faster rate)..

To be fair it's a pretty inexpensive standalone (Apexi PFC ~£400) compared to the competition (MoTeC, Link XLEM etc) - I think even the newer Megasquirts have eclipsed it in terms of speed, but it's still a default choice for a lot of Japanese cars here, in the US and Japan simply because it's plug-n-play for a huge number of cars (even comes with a default map, usually ripped straight from the stock ECU by Apexi so you can plug in and drive on a stock engine)

under normal conditions rs232 can handle more data flow something wrong there..

IIRC each 'frame' is somewhere around 512bytes (4096 bits), and the interface is only 38400bps.. ~12 samples per second

Nothing wrong, just a slow interface.. to be fair I'd much rather the ECU spent it's time calculating fuelling than shepherding an RS232 interface

(Did I also mention that the software used to program the ECU is written in Visual Basic? Well, unless you're an Apexi dealer and can read Japanese, then you can use the 'official' software .. but I'm neither )

1/12 sampling is enough to populate the map with logged A/F ratios and knock levels (and injector times, AITs, MAF reading, etc etc) after a couple of WOT pulls through 3rd or 4th gear, though - and it zips through the map pretty fast in 3rd 

[cem_devecioglu]

p

I can say you need a faster cpu

Nah - the processor in the ECU is doing far more than 12 calculations per second, and the laptop is capable of much more - but the interface between the two is RS232 at a relatively low speed.. so you can only read so myany data points per second (and the ECU insists on pumping out a full frame of data each time of everything it knows about, there's no selective monitoring to have, say, only RPM/load/knock/lambda at a faster rate)..

To be fair it's a pretty inexpensive standalone (Apexi PFC ~£400) compared to the competition (MoTeC, Link XLEM etc) - I think even the newer Megasquirts have eclipsed it in terms of speed, but it's still a default choice for a lot of Japanese cars here, in the US and Japan simply because it's plug-n-play for a huge number of cars (even comes with a default map, usually ripped straight from the stock ECU by Apexi so you can plug in and drive on a stock engine)

under normal conditions rs232 can handle more data flow something wrong there..

IIRC each 'frame' is somewhere around 512bytes (4096 bits), and the interface is only 38400bps.. ~12 samples per second

Nothing wrong, just a slow interface.. to be fair I'd much rather the ECU spent it's time calculating fuelling than shepherding an RS232 interface

(Did I also mention that the software used to program the ECU is written in Visual Basic? Well, unless you're an Apexi dealer and can read Japanese, then you can use the 'official' software .. but I'm neither )

1/12 sampling is enough to populate the map with logged A/F ratios and knock levels (and injector times, AITs, MAF reading, etc etc) after a couple of WOT pulls through 3rd or 4th gear, though - and it zips through the map pretty fast in 3rd 

rs232 was reaching 115kbps when grandma was virgin

agreed.. ECU is also busy reading from sensors but must admit car manifacturers use the slowest cpu/hardware possible and those ecus cost more than an arm and a leg if you try to buy..

so imo microsoft must start custom ecu programming bussiness , so we can send viruses to others cars

[aaronjb]

I forgot to add as well, the interface on the ECU itself isn't actually RS232, it's some proprietary signalling. You're meant to buy an interface from Apexi, but that's only available to dealers - and AFAIK they only exist in Japan..

So what you have to do is buy a little interface box (a "Datalogit") which does the translation from 'something' into RS232.. That's probably where the bottleneck really lies as it's a very basic circuit inside the box - although it does also give you two analogue-to-digital inputs to hook random things up to.

As I say, it's all built to a price point £400 is pretty cheap for a full P&P standalone, and the Datalogit is ~£50 secondhand..

The next project will (if it doesn't end up running a Holley carb ) probably be run on Megasquirt purely because I like the homebrew 'tinkering' aspect, and it won't be my only car (the MR2 was my only car when I put the turbo etc on!)..

Or possibly this: http://www.jegs.com/i/DFI/310/77011W/10002/-1
To go with this: http://www.twminduction.com/v8_kits/427_with_filters.html