Thread: D2 4.6 conversion owners. 4.6 ECU swap & EOI.

Thanks for that Mark,,

so the reprogramed ECU's that you sell have a better output than standard?, across the entire rev range?, using standard 4L inlet parts?

I dont suppose you can add both 4 and 4.6 tunes and make them switchable?

just for future expansion as it were---

Wow! You're not called Pedro the Swift for nothing are you???

The software only contains one very specific set of maps and configuration information at a time, so sadly it is not possible to have them switchable as with the older GEMS system which could contain up to four tunes.

Probably the biggest pain with the upgrade (apart from the price) is that I need to have the ECU here to modify it, which will stop a lot of people going for it. Once I have the ECU I can suck it's brains out, and then modify the tune. The vehicle tune information is then securely backed up here, meaning that in future I can produce exact clones where required, again with any modifications as required (e.g 4.0 to 4.6).

What many of my overseas clients choose to do is to fit another similar used ECU to their vehicle temporarily, and send the original over here. Once the upgraded original comes back to them, I can then clone a standard tune into their spare ECU so that they then have an interchangeable standard one.

Sorry but I didnt' fully answer your question.


The Bosch engine is mapped in such a way that it produces maximum power when it hits the Rev Limiter, which is set at 5500 RPM. At this point the mixture is rather rich, but the ignition timing is fine for good power production.


Therefore the peak power will not improve more than 2-4 BHP with any upgrade, unless the Rev Limiter is moved up to say 6000 RPM. Although I could do this and the power is still increasing when it hits the Rev Limiter, it would be something of a “smoke and mirrors” or Snake Oil improvement. Power increases here are largely academic, since the vehicle will change gear long before this limit is reached.


However the dominant engine characteristic is actually a huge hole in the torque curve, centred around 2500 RPM. This is filled in very well with the upgrade, delivering an extra 10-15 lb/ft of torque and much faster throttle response. Economy improvement is 10-15%, although it is possible to angle the upgrade for ecnomy or power.


As we all know when driving a standard vehicle it actually pulls away from a standing start quite well initially, but loses interest once it gets to 3000 RPM. Personally I find this trait especially annoying, and it doesn’t even sound like a V8 either! All the action happens on the first or last quarter of the throttle pedal movement, and the bit in the middle doesn’t make a lot of difference. It is also a real nuisance to my clients who tow, since it often means the gearbox will kick down two gears when they only wanted a bit of extra effort (on a gradient for example).

Obviously the situation is different when putting a 4.6 engine under a 4.0 tune, which can still be disappointing since the lean mixture and retarded mid-range ignition is still a feature of the underlying programming.

late edit; retyped after your last post

thats better,, and answers most of my edited questions

yep, midrange is the problem.

Originally Posted by Mark Adams

The 4.6 Disco II was only sold in the NAS market, and it was fitted with the high-compression version of the engine. All of these vehicles had SAI (Secondary Air Injection) without exception.

Actually there are some 03 and 04 Discovery (the only years with the 4.6L) over here that don't have SAI.... there are just so few that I've not seen any. There are a few guys on discoweb.org that work on them for a living, and even they have only seen one or two.

2004 Non-sai 4.6 Engine bay pics needed - DiscoWeb Message Boards

Im a bit lost here. I have a mate with an 03 D2a with a 4.6 RR motor with quite a bit of performance work and lumpier (not by a lot) cam than standard. Its running stock 4.0 intake runner, air box and MAF - and ECU. It goes hard without pinging. My stock 4.0 can ping at times even when warm and always running premium....MR did this work

TRS reckon the 4.6 they do will run stock ECU and MAF and no probs...so...is it a one off situation for pinging with the 4.6?

Cheers

It definately runs, but it will ping under certain conditions and load and most importantly fuels.

I'm running std MAF I measured a few and couldn't find a difference

Originally Posted by jafir

Actually there are some 03 and 04 Discovery (the only years with the 4.6L) over here that don't have SAI

Thank you for that Jafir! I'm old enough to know better than to say "without exception" when talking about Land Rovers!

Of course I would love to see one of these vehicles, and even better get an ECU off one to have a look at. Do you know if these also have the larger AFM too?