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MadDogMoggy 20th April 2011 23:36

Honda ECU choice (Type R)
Hi All,

I came away from a 'tuning' session yesterday feeling very dispondant: having hired a trailer for the day, borrowed my dad's mate's 4x4 to tow it, and then taken the 5Exi-R to a local rolling road to get it mapped for SVA and made very little process I'm looking at alternatives. Any advice would be appreciated.

Having ummed and ahhed during the build I decided on a Z-cars engine loom modification and Hydra EMS, as I'd seen them at kitcar shows and they seemed to do a good job on their minis. However staring the car for the first time was very difficult and the engine was running extremely rich - making the exhaust and plugs black in the short time we ran it. I obviosly needed to get it remapped.

I took it to a local tuner, who played with it for about 4 hours, although it was my laptop the mapping software was runing on, connected using my lead, and I was the one changing the values on the map. It became obvious that I would need to take it to someone used to the Hydra system on the K20A2 engine, ie Z cars.

Unfortunately they are over 350 miles away - ie day travelling there, day travelling back, and a day getting them to remap the system, plus two nights over night accomodation, trailer hire, diesel etc. I could end up paying as much again as I did for the system in the first place!

So what have you other guys with type Rs done? Hondata (which is about 170 miles away and would also need a remap to meet SVA regs) or another options (Marlin's 'tweaked' ecu) or something else?

Any suggestions would be welcome, as dad and I were close to putting a rag in the fuel tank and lighting it yesterday!

Thanks again in advance of any help (even if it's the best rag to use)

chrislandy 21st April 2011 10:04

Any competent tuner with the correct software should be able to put it into a decent state of tune (unless the z cars thing is over complicated). I made the mistake in thinking my engine would need to be fully mapped for the SVA but they only check the emissions at idle and fast idle iirc. In the end I "tuned" mine on the drive to idle within the lambda required using a wideband o2 sensor and rev nicely then took it to a local friendly mot station, slipped them 10 to use their emissions tester, plugged the laptop in and got the HC's and Lambda within the test critera - you have to be quick though as you don't want it to get so hot the compensation tables kick in. I also took the lappy to the SVA test and was able to tweek it a little to make it pass on the day

MadDogMoggy 22nd April 2011 16:56

The problem that we had was that the guy wasn't familiar with that particular software or engine.

He basically sort of did what you suggested - put a sensor in the exhaust and got me to change values at different rev settings.

The base map had values of 8.something down to 6.something for each 'cell' of the map.

By the end of the session we reduced these to 3s, 2s and 1s, but it was still running rich.

We also inly did this in the 0mmHg column, which the engine seemed to be running in for most of the time, butthen suddenly started toswitch to the 50mmHg column. He didn't seem to know what this meant or why it was!

From scanning through the formums it seems most people have gone with Hondata wich has come with maps that they can use from the off.

Going to do more research and then seriously consider what needs to be done.

Thanks for you reply

chrislandy 23rd April 2011 13:16

You could try signing up to Seloc (lotus forum) there are loads of people on there with TypeR experience and possibly someone who could email you a map.
The mmHg will be your manifold pressure, this will vary depending on the load and RPM of the engine, it is likely the engine is operating somewhere between the 0 and 50 and thus switches between the load cells. On idle, mine tends to hunt around 4 cells (2 rpm and 2 pressure) because its running nearly bang on between the 4. It might be worth trying to find a different RR if you can travel to Cheltenham theres a place called Mech Motorsport who are pretty good, there is also one in Somerset somewhere I've heard good things about (although I can't remember their name at the moment!)

alackofspeed 26th April 2011 00:18

The problem with mapping the K20 is most tuners aren't familiar with the analogue adjustability of the cams, with closed loop control.

The honda requires many more maps than a static cam engine. For example the fuel tables consider load index, revs, cam angle, and high / low cam, in addition to the usual coolant temp, intake air temp, tps......

They are reputably difficult to map without experience, and from what I've read, many of the standalone ECU options can't exploit all the features of the engine.

By the way, you don't need to remap to get a stock K20A2 through an emissions test if running Hondata -the stock map is a very close approximation to a UK OEM Honda ECU calibration, and runs a stock engine absolutely fine. A few of us have put our cars through the test using the basemaps.

MadDogMoggy 26th April 2011 16:55

You're right - he didn't have a clue about the engine or mapping software!

It's good to know thatthe Hondata will get through SVA/IVA on a standard map. I take it that it comes with one? Talking to the main agent and trying to get him to say whether it would or not was like trying to get blood out of a stone!

How easy is the hondata to wire up? I take it the standard engine loom plugs into the ecu, and then the other necessary wires plug into the other side of the ecu. I'm using a race Technology Dash2, so at the moment most of the Marlin loom wires are connected to it instead of the Rover instruments.

Is it possible to buy a connector that fits into the other side of the ECU, or have you just pushed on individual wires?


craig 10th May 2011 19:13


Originally Posted by MadDogMoggy (Post 21374)
Is it possible to buy a connector that fits into the other side of the ECU, or have you just pushed on individual wires?



Yes this is what I did! I think it cost about 12 and I bought 2 of them but I have looked for the other one and I can't find it! I seem to remember it took me a while to source though.

This was about it for my wiring as the rest was a standard cheap/home modified loom just connected to the ecu and it works

As far as sva goes John is right about hondata base map as mine pissed sva on emissions even with a race cat on.....guy even said it might have scraped through without in theory although it's needed for test.


MadDogMoggy 11th May 2011 17:24

The decision has now been made to go down the Hondata route, following coversations on the forum, chats at Stoneleigh and a visit to another Type R builder who only lived 23 miles away!

Part of the problem has been our build time (nearly 6 years now for various reasons) and in that time people have found that the Hondata system works out of the box, and I have found that the Z-Cars system, although popular for mini conversions, doesn't!

It would appear that the E connector on the Honda ECU only needs about 6 connectors, and I've pulled apart a connector from another Honda loom which the individual pins will fit on, so I'll just push them on individually.

Fortunately I kept the original ECU, but I now need to get hold of an engine/charge loom and then the Hondata system.

Thanks everyone for your help so far

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