Took the Plunge..

[Beagler]

Have booked car in at Northampton  Motor Sport to have the ecu  Remapped/replaced to stop the pop and bangs and move the power curve further down for road use. Whist they have it fit a lighter flywheel and clutch assy.  and a few other associated jobs.Troy and Martin are very helpful to talk to and am impressed with their knowledge. Their charges are very reasonable also.

[BenF]

Great!  Northampton Motorsport are very good.

I'm guessing there is a bit of a wait for the rolling road - I know this is their busy time.

[Beagler]

Yes booked in for mid July. Licky to get in then

[StevehS3]

I can see why you want to have the pops and bangs on overrun taken away. Can they re-map your existing ECU? Please let us know how it all goes and how the car feels after the upgrades.

[Dave Hardcastle]

They are a great outfit. I had a lot of ECU issues when I first bought my current car. Sometimes they can remap an existing ECU if they have the unlock code for it. I ended up with a new ECU, which has side benefits of being more modern and therefore quicker in operation.

My car was literally transformed when I collected it. I think you'll be very pleased with the work they do, good decision.

[Shortshift]

I know that Troy and co are very good at this but so is Steve Greenald (of 'Two Steves' fame) - with the important difference being that Steve G can remap Caterham-encrypted ECU's.  So no need to buy a new, unlocked ECU.  And, from what I understand, there's little or nothing to gain on any Caterham by moving to a "more modern ECU", except perhaps for 620s where extra channels are needed for fuel pump control.  So, a £600 job with Steve versus something approaching twice that elsewhere...

And if the OP's objective is to "move the power curve down for road use", isn't that more a function of engine mechanical specification and set-up (particularly cam timing and profiles) than by fueling and ignition timing changes via a remapped ECU?  I fully appreciate that remapping will make the most of what the engine is capable of, but surely if the objective is to alter the mid-range torque-curve characteristic, there are more effective ways to achieve this?

James

 

[Beagler]

Having spoke to them I am happy for them to do the work.

[BenF]

James, you are absolutely right.  The fact that Steve Greenald can remap without you having to buy a new ECU does make it attractive.

I had a session booked with Northampton Motorsport for my CSR but ended up cancelling it because the car runs fine, except when cold - and even managed to pass the MoT legitimately.  The cost of the session, plus an extra 600 pounds for the ECU, meant that is was going to be an expensive box ticking exercise.

My understanding is that the generic map they put in Sigmas is not very good so I guess that's where the gain will come from.  I assumed that was more top end but maybe also lower down - could someone who's had their Sigma remapped can confirm this?

[Beagler]

I can see it was a bad Idea posting my intention. No need for me to post anyfurther.

[Shortshift]

Not a bad idea at all.  The point about a forum is to share experiences and ideas and - importantly - to leave a trail for others who may come along later looking for guidance and answers.

An open mind to the suggestions and comments made by others, in good faith, helps to make the forum a rich resource!

James

[StevehS3]

So many have reported good results in terms of drivability and fuel economy from a rolling road session for a variety of engines including Sigma and Duratec.
You would expect CC would use one of the reputable rolling roads for mapping a new car/engine. I find it hard to believe that each individual engine needs its own bespoke map.
I have wondered if it is more to do with the lack of sophisticated idle control such as idle air control valves and the sensitivity of the TPS and throttle stop rather than differences in the engines. 
Any thoughts? 
#9 Please do let us know how it goes. We need more experiences like this.

[BenF]

Beagler, why are you taking such an odd attitude?

Presumably, you spoke to Northampton Motorsport and they said that yes, with the mapping they can move the power curve lower down for road use.  People on here are questioning this - which is fair.  Has there been a misunderstanding about what is possible from a mapping session? 

Or are you upset because people suggested a cheaper option, i.e. using Steve Greenald, which will save you the cost of a new ECU (560 quid + VAT if I remember correctly)?  Don't you think that such a suggestion might actually be helpful?

[John Vine]

#11:  You would expect CC would use one of the reputable rolling roads for mapping a new car/engine.

That's an interesting point.  I've always understood that, before CC introduce a new engine, they commission a "generic" map from one of the experts (I think Steve G is the go-to man for them).  Whether that map will subsequently suit all versions of that engine is unclear. 

Steve remapped my R400D some years ago when it had a plenum, and he transformed the driveability.  When CC fitted my roller-barrels, they also loaded a revised map.  I don't know how that was derived but it's proved remarkably good.  The car goes like a scalded dingbat when stirred, yet will pull 6th gear at 1500 rpm without a hiccup or murmur, and gives (relatively) good economy.

#9:  I for one would be very interested to hear the results for the OP's Sigma, so I would encourage him to keep in touch with us.

JV

[CycleSi]

Actually, Troy can access/unlock MBE ECU's too. He did mine and mapped it perfectly.

That said, I have also used Steve G/Luke S and they are equally excellent.

You're in good hands with either.

[StevehS3]

#13 I was wondering what a generic map actually is. Taking the 310 as an example, is that simply a map for a Sigma Ti-VCT engine (and let the lambda sort the rest out!) or has a 310 Caterham with the correct cams, air intake etc been mapped on a rolling road? My assumption is the latter but then I struggle to understand what is so greatly different between one 310 engine and another. It would be good to have input from CC on technical questions. 

[John Vine]

#15: It would be good to have input from CC on technical questions. 

It would indeed.  I've just emailed Tony Mills to see if he can shed any light on this.

JV

[StevehS3]

That's great John - thank you.
I certainly don't feel like I properly understand why so many cars need to be re-mapped.

[John Vine]

#16:  Well, I've just received an ultra-speedy and helpful reply from Tony.

This is what I asked:

"There's a discussion currently running in the 7 Club concerning the remapping of Sigma and Duratec engines (by experts like Steve Greenald, for example).

When you supply a new car, does it come with a "standard" or "generic" map, designed for that particular model? If so, how is the map created originally? For example, do you commission a mapping expert (such as Steve G) to create it, perhaps when the particular engine or variant is to be first introduced? And if so, would you subsequently upgrade these maps in the light of experience and feedback?

Any light you can shed would be much appreciated!"

And this was Tony's reply:

"In the first instance, when we develop a new engine, it will have a map created by someone such as Steve Greenald.

We will create a different map in the same way if we upgrade the engine e.g. 360 to 420 spec or roller barrels fitted.

Sometimes the engine can appear to be the same but a different map would need to be created if for example the injectors spec or fuel pump changed.

As a result we have a lot of different maps for the same engine type."

I think that's very helpful, and confirms my initial understanding. 

#17: Like you, I don't understand why so many 7s need remapping.  Are the "generics" so bad?  I really doubt it if they're created by experts like Steve G.  In my case, Steve changed the mapping strategy from MAP-based to TPS-based, so I can see why that would be a good move (especially as I later moved to RBs).

JV 

[Jonathan Kay]

Thanks, John.

Jonathan

[Golf Juliet Tango]

When you consider how many owners modify some parts pf the engine, it is hardly surprising that we keep the rolling roads busy. 

The reply JV received shows that Caterham Cars install maps specific to each engine model. That seems fair to me. The idea that each and every one of their 500 car production should have an individual rolling road session isn't feasible or affordable is it?

[Dave Hardcastle]

#6 James, Northampton Motorsport can unlock 'some' ECUs, as I said, It's just not guaranteed they'll be able to unlock everyone's. If they can unlock it, obviously they can then remap it, negating the need to purchase a new one.

NMS told me that a new ECU carries out its duties quicker as the processor/unit operates faster, the increase in processor speeds being well and generally known. My car being a 2008 and the new ECU I had fitted being 2020. It sounded totally logical to me.

[StevehS3]

Thank you very much John and CC for the speedy reply.

I agree that the original CC map should be good. Perhaps in some cases the cars have been re-mapped by the person that did it originally. TPS setting, throttle stop and ensuring the exhaust primaries aren't leaking would be good checks. I have had noticeable improvements by the slightest adjustment (barely visible on the screw) of the throttle stop and sealing the primaries. 

[aerobod - near CYYC]

I think the issue with Caterhams and generic maps is the accuracy of fuel delivery needed close to idle. The injectors are more accurate at full flow, but variations at only a few % of full duty cycle combined with other tolerances such as sensor accuracy probably will give variations up to 10% or more between each engine at low fuel flow. Most OEMs either use secondary idle devices or more sophisticated Lambda control to overcome this. I would say 5% variation is probably the most variation that a stable idle would need, although the Caterham rudimentary Lambda control can likely achieve this for a good proportion of engines, but not for many consistently, hence the need for a custom map to completely alleviate the low load problems.

The variation in fuel flow near the redline is probably more like 2% from a tolerance perspective, so less of an issue, although 2% variation around the ideal Lambda of 0.86 or so at full throttle near peak power is about the maximum variation you want to have to achieve optimal output, 1% would be better to keep the Lambda in the 0.85 to 0.87 range, which again would require a custom map.

[John Vine]

#23   ... hence the need for a custom map to completely alleviate the low load problems.

I imagine that would be why Steve G managed to improve the low-speed driveability so spectacularly on my plenum-equipped R400D.  In fact, when he'd completed the mapping, he invited me to take the car for a spin, saying "no improvement, no charge".  He knew that was a safe bet!

JV

[Shortshift]

Replying to #21

Dave

I am not aware of any recent Carterham ECUs that require 'unlocking' (as with a PIN code, or similar); maybe this relates more to older, legacy ECUs? 

My understanding is that all contemporary Caterham ECUs are encrypted (rather than locked) and that this very much limits who can access them for mapping.  I am not aware that NMS can map encrypted ECUs, whilst Steve G most certainly can (leading to a substantial cost saving from avoiding the need to purchase a new ECU).

I don't dispute that an MBE 9A4 is a faster and better device than the older MBE units, such as the 992 model.  My point, though, stems from my understanding that the increased speed of processing is of negligible benefit when applied to a typical relatively straightforward Sigma or Duratec engine as found in many modern and recent Caterhams.  A better ECU - yes, for sure.  But of any real benefit - apart from the specific issue I mentioned relating to 620 fueling?  I gather not.

James