51x

Is it a completely standard ECU (ie. has a glued in EPROM and no socket)?

:) You didn't steal it John - you suggested 4 maps, so I thought I'd better come up with a way to do it with the bits I've got. Of course, your method will end up better because having the daughter board means you can stick other stuff on it (eg. optoisolator). It's probably not that hard to do but I'm a lazy b*stard ;) There you go, it can forever be known as: "The Lazy B*stard 4-Page EPROM" :cool:

Well, the Mines mod used a 27C1001 (1Mbit) but it needs a daughter board because it's got more pins. So it doesn't really fit in with the plan of grabbing a few cheap bits and slapping them together (which anyone can do, right?). I don't wanna be accused of ripping Mines off either (not a dig at you Chris) - not that it'd really be a problem, because it's an old design and I don't think they'd give a stuff. Besides, it's kinda convenient to be able to whip the top EPROM out, erase it / re-program it and still have one in the ECU in case you need the car. It's a different way of doing it. Maybe not the best, but convenient.

H'oi! They just didn't finish it (s'cuse the pun). And they weren't / won't change(ing) that for it.

Yeah, tell me about it Chris! I've started getting all interested in this stuff again because I'm finally a 300 driver again! I'll probably jinx it just by talking about it, but it's booked for Pete to be doing the mapping and injectors next week. It's gonna kick ass! When are you expecting yours back? Anyway, the mod's a slice of pie to make (not quite a piece of cake, but almost). It's probably too late to be talking about it... I forgot to mention: programming is the same as the 2-page mod, except you've obviously got another switch to flick, and I also forgot to say pin-20 on the bottom EPROM should be bent out so it doesn't connect with the ECU (unless via the switch). And you need to pull the top EPROM out so you can erase the bottom one (obviously really). And, you don't have to stuff a 27C512 in the top socket - if you've only got a 27C256 you can use that instead. Obviously, the 1st switch won't have any function if the 256 is selected. And I /really/ forgot: the second switch most DEFINITELY shouldn't be switched while the car is running! There'll be a point where the switch isn't quite connected to anything, which means the ECU will think neither EPROM is connected. It'll basically miss a whole load of instructions it should be executing and could end up doing something horrible. And I should probably also put some sort of disclaimer... you mess with your ECU, you run the risk of screwing it up. I'm not responsible. There, how's that?

Twins ;) Has Warren got one big turbo?

You'll never guess what I've gone and done. This one's a bit more complicated than the 2-page one, and uses more bits. But it's still less complicated than the Mines way of doing it, (again) it's not based on what they done, and it doesn't need a daughter board. For this, you basically solder a socket on top of a 27C512 and connect all pins together except pin-20, which you leave apart. Bend up pin-1 again. Basically, do the 2-page mod first... this gives you the hi/lo selection in the both EPROMs. The second switch is to select which EPROM will be used (top/bottom). Unfortunately, the EPROM that's not in use at the time needs it's pin-20 pulled high, while the in-use EPROM is connected to the ECU socket. It can be done with a 6-pin (double throw) switch. I'll stick a pic up and the details when I've yanked it out of my car again. Wiring to the second switch basically comes from the 2 pin-20s on the EPROMs (one on the top socket, one on the bottom EPROM), the pin-20 from the ECU socket, and the 5V pin (pin-28). I tried it out earlier and it works just loverly. I'm running standard UK and SE in the bottom EPROM and the same again in the top, but with the rev limit set to 5K and the speed limited to 85mph (137kph). It actually topped out at around 90 on the speedo (it's great having access to a private track), and the rev limit kicked in (rather violently :) ) at pretty much 5K. Alright?

...and another one of the EPROM being programmed in my home-hacked programmer (just don't cut the black wire)...

So I thought I'd stick up a pic to show /just/ how complicated this 2-page EPROM is to make...

Hahaha! :D And there's me trying not to mention Devins stuff in case someone here gets in trouble for posting a link to modified Nissan EPROMs. Cheers tho Duff... if anyone hasn't looked at Devins ECU tuning page, it's well worth a read.

Well, OK... a thumbs up from AndyP! :D Just need: a nice little tool that can make difference files (and undo them back to the real thing)... and a bunch of people ready to do some tuning. John Dixon's made a nice Z32 tuning spreadsheet, and is still adding to it (just now talking about adding import/export of 512kbit (2-page) images). And ROM Editor is OK for a bit of a play.

That's fair. Could you get in the same trouble for having links to someone elses copies of complete EPROMs? Anyway, even if this is a problem, if someone wants to share their re-map data (for example) maybe you could host only the differences between that and a standard EPROM? You'd host a small difference file - a bit like hosting patches for console games... which noone's got in trouble for doing (have they?). This would have to be limited to home-brew stuff tho - no commercially available data (JWT, SE, etc).

:D Oh, OK. I dunno who you're talking about then Chris (give us a hint, eh). You have seen a Mines ECU because you've checked my rides section ;) I can tell you how they do it in the ECU I looked at, but it's nowhere near as simple as the method I suggested here. Do you want your stick back then, cos it smells kinda funny.

Eh?! Hold on now. If AndyP was suggesting I simply ripped off a Mines product and was trying to sell it, then I completely missed that. I have looked at an old Mines ECU (as you well know) but this info certainly wasn't based on it. This is a cheap and simple (pin-compatible!) way to run 2 maps in a 300 ECU. I thought it up on my own - it sure aint rocket science. And I'm not trying to make any money from it. Maybe I've got the cr*p end of your stick?!

Woops, I've only just seen this. It was my maths homework... really it was just a comment on what nobs some people are. So it went like: nob reckons he can do a 12.5 sec 1/4. But also reckons his 0-60 had dropped to 8 secs (did I say 8 originally?) because he's got a 10-ton sound system. Showing all working out, and using diagrams where appropriate, prove scientifically: this bloke is a bull-sh*tting bell-end. He probably never even ran the car. He probably just looked up some 1/4 figures hoping to make his story sound "believable". Never mind. Interesting numbers tho.

Bl**dy h*ell, you bet I'm jealous! (still prefer my UK seat belts tho ;) ). Where's the switch to control them then? And (dare I ask) how much hassle to do a conversion?

Sorry... I'm having one of those moments... you guys are saying you've got electrically folding wing-mirrors?! Is this a Jap thing?

:) No probs. You were one of the people I came away thinking: I should've had a better chat with him. And Warren. Nice to put a few faces to cars tho.

What? You're actually getting closer to making a dedicated ECU tuning section? :eek: Pushed my luck now, haven't I?!

Crikey, James! I make one comment about your wheels looking dirty and you avoid taking a pic of my car from every angle! :D

As of last night, I'm running a switched 27C512 in my ECU. It's currently programmed with standard UK and one of SE's. You simply select by flicking a switch. How it's done (quoted from a recent email)... " The EPROM mod is very, VERY simple. Basically you're pulling pin-1 high or low with a switch to select page-1 or page-0. You'll need a 3-pin toggle switch. It's just for safety that I bent out the address pin (pin-1) because I don't know what effect it would have on the ECU if connected. And besides, you could damage your EPROM programmer if it's not bent out. So... pin-1 of the EPROM you then wire to the common pin on the switch, pin-28 wires to one of the switch select pins, pin-14 to the other switch select. You wanna make the wires long enough that the switch will come out of the ECU, but not so long you won't be able to stuff it all in the eraser. To be absolutely safe, you should really stick resistors in series with the pin-28 / pin-14 wires... just in case the switch gets wet - you DON'T want these pins to connect together because you'll be shorting the ECU's 5V down to ground. To program, select 27C512 (27C256 won't work), import your 27C256 image into one half of the 27C512s memory block - it doesn't matter which, because the switch now defines which half of the EPROM you're programming - then program that half. The verify will fail if you program the full memory because it'll get a mirror image in the second half. If you want to program the 2nd half, flick the switch and do it again. Obviously, if you erase the EPROM, you erase both halves. I wouldn't advise switching maps whilst driving... most definitely if the code versions are different. I dunno what the ECU would make of suddenly having completely different maps, even if the code versions were the same. It might be OK. " And another bit... " Forgot to say... the EPROM mod also needs short wires to stop any potential noise problems, ie. long wires will pick up spikes and, at best, cause the pages to flip about... at worst, damage the ECU. If you wanna dash-mount a switch (I probably will in future) you should really hook up something like an opto-isolator right at the ECU end and run a couple of wires from that. If you don't already know, an opto-isolator is basically an LED and detector in one small package - the input and output signals are electrically isolated from each other so high-voltage spikes and noise'n'crud won't mess with your ECU. " OK?

Very well done all :) Just the sort of answers I was looking for. But still surprisingly surprising. On the face of it, I actually thought it could be possible with a /serious/ burst of power. But it sounds like we (you guys, actually) have proved not even Johnny Fartpants would be able to generate that sort of rear-end rush. I like the image tho: rear window out, huge stream of cack, car straining to stay on the strip. Nitrous? No way. 60 to 330 mph in 4.5 secs?... maybe possible with an SRB strapped to the roof?! Or... and this is probably more plausible... he's running a secret custom flux capacitor that kicks in at 60 mph and delivers him to the finish line just in time. The real giveaway would've been the double line of flames left on the strip, of course. Just wish I'd been there to see it. Sounds like he didn't even think it was that quick either. Maybe it wasn't running too good that day? :D

Our accountant at work seems to have lost the ability to add up. Which is a bit worrying. As it happens, he's got a well-established record of being full-o-sh1te. I thought you lot might find this funny. He was telling me today he took his E36 M3, soft-top, nothing done to it except a heavy sound system, to a RWYB recently... where he ran a 12.5 sec quarter. In the same conversation, he said his 0-60 had dropped to 8 secs(!), because of the weight of the sounds. Now it struck me that, during his 1/4, if he'd only hit 60 after 8 secs, it shouldn't be that hard to work out how far down the strip he'd run. I s'pose you'd have to assume he'd linearly accellerated(?!) up to that point to get the distance - not the best way. Is there better? It sounds like he'd have a heck of a lot of catching up to finish the rest of the 1/4 in just 4.5 secs. A sudden burst of speed? A thousand shot of nitrous? Just for fun (because obviously it's bull): 1. what speed would he have crossed the line at, to actually finish in 12.5 secs? 2. how much increase in power (eg. nitrous shot) would be required to accellerate this bucket of poo from 60 to the final speed? I'm trying to stay off the subject of his (soon to be!) 600 bhp RS4. I assume that figure was plucked out of the sky since he heard my 300 would be (hopefully) 500+ bhp. People who can look you in the eye and spout a constant flow of bullsh1te... how do they do it? How stupid do they think the world is?!

Digital speedo! Wow... my mates got an Astra with one of those! Cutting edge technology, man ;)

Hahaha! :) That's obviously what I've been doing wrong. Can I mention your name next time?