AncientGeek

Thanks for advice (and kind offer) I was surprised to find the pistons are readily available here (and cheaper than importing). The question is becoming more of resleeve vs rebore but I will take the engine out and measure up before buying anything. Problem with used 3.9's here is that that are usually equally poked if not worse. I replaced my rockers and rocker shafts about 20k km ago and the heads look good. Peering through the valley the cam looks OK and I will replace lifters.

My 3.9 V8 D1 is at 240k km and I have the heads off atm. The bores look sick with a nice fingernail flicking ridge. Had them measured a and they are 3 times over the allowable limits. Look at my location and you will not be surprised that options are limited locally. So I'm looking for UK supplier for 3.9 9.35:1 20 thou oversize pistons & rings at reasonable cost and who are happy to courier to me. Shipping will cost a whole lot more but that's a death and taxes thing. I was thinking of realsteel. Any other suggestions? A possiblly available local option is the allparts pistons assemblies. Am I right to be cautious about them? Other than the megasquirt and tubular headers the motor is stock. Family holiday car.

This is the one I use with MS1 and MSDroid http://www.ebay.com/itm/RS232-Bluetooth-Serial-Adapter-Communication-Master-Slave-2-Modes-MINI-USB-DF-/331729183618 You can't just plug it in. The RS232 is the wrong sex and the pinouts are weird. I had to make a custom cable but it works great. I like Cheesy's method.

It's not installed.

There will be something soldered to JS9.

35 bdc at WOT? Doesn't it ping?

My reason for thinking of a rpm> 700 signal is if the idles dips, the aircon will turn off and raise the rpm. I have had problems going down a steep slope with a/c on and the engine stalls. I could also use that for the wide band as they do not like being on when the engine is not running. However I am loathe to remove my beautiful conformal coating to do more mods.

Aircon is also vital where I live. I got mine working on my '97 D1 no problem (MS1 install). Here are my notes from the install. The aircon wiring depends on the Lucas ECU and stops working when you disconnect and remove the old ECU. There is an easy solution. Remove the yellow-black wire from the AC logic relay, and put it on pin 86 of the AC clutch relay. You won't need the AC logic relay or the fan timer unit any more. In future I might configure one of the extra outputs from MS to an “engine is running” signal. Then wire that through the AC logic relay so that the AC clutch can only be engaged when the engine is running. (I never did this as it works fine. If I ever do change it I might make it an rpm>700 signal)

Not a lot of that is at much more than idle. Very lean. MAT maxes out at about 26 so not much air temp correction. Your lambda authority is clearly set to 0, thats why gego is 100 throughout. Either not tuned, or mechanical problem.

Doubt it. I was getting temps of 60C in the engine bay before I moved the IAT out, and even that did not affect running, only hot starts. How's your fuel filter?

Is this a 300 series 3.9 Disco? As I remember there is a big white connector under the dash that connects just about everything coming from the engine bay. The spider wiring is a pain but after ripping out the spider and its wiring completely it was clear what goes to what. The thin wires going to the spider can just be cut off, the thick wires you must work out which is which (they are helpfully all black). I also remember RAVE was not much help. Also ask yourself if its really necessary. If your wiring is good, leave it there and just add the few extra wires you need. You can re-purpose some of the MAF and stepper motor wires. Then cut off (or splice into) the wires on your current ecu connector. Could save a lot of work.

Thanks for reassurance Quagmire, discovered a blocked fuel filter (only 15k km old) Suddenly the excessive pressure in fuel tank makes sense. Murphy is doing this to me a lot lately, you change something and it breaks. Now OBVIOUSLY the change caused it. But no, its something unrelated that just happened to break at the same time

I recently tried the hires firmware HR10g and I was very pleased with the results right up to the moment when it lost power and died 250km from home. Could not see anything wrong, restarted and all was well. Approx 250km into the return trip exactly the same thing happened. It feels as if the ignition is suddenly retarded by 40 degrees. Restart and its as if nothing was ever wrong. Unfortunately I was not logging on either occasion. The edis unit felt a little hotter than usual but that could have been because I was panicked and it was 40C outside. Took the ecu out and ran it on the stim for 48 hours - no probs. Only thing I changed was the firmware. That could be coincidence though. Its a standard Nige type edis-8 install. I could just go back to normal firmware. And maybe have the same problem. Not an easy thing to test. Any ideas?

Getting a vacuum buildup in my tank on long trips to the point of worrying about collapsing the tank. I had a look and studied rave but cannot figure out how it compensates for vacuum. There's a breather pipe going to a box on the inside of the fender above the filler. This has another 2 pipes, one goes to the charcoal canister, the other going to atmosphere, presumably an emergency vent. These have pressure valves on them and seemed to be designed only to work with positive pressure. The fuel cap is sealed Unless one of these or the charcoal canister act as a one way valve I cannot see how vacuum is relieved. What am I missing?

I also use that technique but I go further. First of all beware of using examples from England if it gets hot where you live. A real air temp in the high 30's is not unusual for me. I moved the mat sensor out the engine compartment. Modified the airdenfactor.inc to reduce correction by approx 50% and recompiled. Subsequently fine tuned by analysing log files looking for ego correction at different temperatures. I admit I am defying the laws of physics by doing this. Also added IAT correction like yours but mine starts at 40 degrees. Stops at 1500 rpm. If you modify airdenfactor.inc you might consider another mod which I came up whith after having a sensor failure. MS is designed to default to a limp value if the sensor fails but it did not work for me as you never read 0 ohms or infinite ohms across even a disconnected sensor. Consequently my engine was being fueled for -40 degrees. So I extend the use of the limp home value. for example the top of my file look like this: DB 100T; 0 - sensor failure, use limp home value. DB 100T; 1 884 474 10 ohms DB 100T; 2 654 346 20 ohms DB 100T; 3 554 290 30 ohms DB 100T; 4 494 256 40 ohms