Anyone seen/used these before?

[slystiguy]

I was just curious

http://www.trademe.co.nz/motors/car-parts-accessories/subaru/ecus/auction-473305734.htm

[Stoffa]

I would happily use one but just get it spun up on the dyno to make sure its safe

[Joker]

prova are generally tuned to the car/setup as well iirc

[Wiretap]

According to Prova their ECUs are good for 'normal' fuels, not as agressive as Mines, ZS and the like. They're tuned for cars with 'stage 1' mods, that being an exhaust and intake. You should be right, but as Stoffa says, you're best to put it on the dyno.

JoKer: Prova ecus are an 'over the counter' item, you send them your factory one and they send it back chipped/reflashed

[STiNGR]

personally i wouldn't use these pre tuned ecu's that come out of Japan. As the auction states they are tuned for a high octane fuel which is unavaliable to us here in nz. I had a panspeed ecu in my batman before i went to a power fc, from what i heard the guy that brought my tuned panspeed ecu had it in his car and the vehicle caught fire due to ecu. It was tuned for 100+ octane. so im just saying be very cautious.

[Wiretap]

Cars don't catch fire due to ECUs... That's the most bizarre remark I've ever heard.

I'm also under the impression that '100 octane' is nothing more than a myth from the '90s and that they use 95 and 98 like we do.

[xsvpwr]

dont use it man your car will catch fire. Ahahahaha

edit: dammit wiretap beat me

[STiNGR]

ran lean, overheated. as i said from what i heard.

[B4 2000]

 Wiretap said:

I'm also under the impression that '100 octane' is nothing more than a myth from the '90s and that they use 95 and 98 like we do.

That's not a myth, go watch initial D, you'll see 100 written on the pumps they use lol

[Wiretap]

 STiNGR']

ran lean, overheated. as i said from what i heard.

Car won't overheat due to running lean either, running lean will either cause det or high EGTs if not det. Car could have blown a HG and then overheated due to running lean, but overheating won't cause it to catch fire either. For fire to occur you need a fuel and an ignition source, ignition source is not hard to come by but unless you're leaking fuel or oil you don't have a fuel.

[quote name='Wiretap said:

I'm also under the impression that '100 octane' is nothing more than a myth from the '90s and that they use 95 and 98 like we do.

/quote]

That's not a myth, go watch initial D, you'll see 100 written on the pumps they use lol

Initial D is a fictional show, remember that Octane ratings are not written on pumps in Japan

[B4 2000]

it's fictional show but still awesome and they wouldn't just put 100 for the sake of the number.

but ya i know for a fact they have a 100 RON on pumps (called super something), i got few japanese mates and they confirm this "myth" as well as my mate who went there for a holiday and he's a JDM nutter so didn't let that "myth" just by without asking.

Although, there's a rumor/chance that they only introduced the 100 RON to the public around mid-late 1990s so performance cars made before that are tuned to whatever used to be the highest at the time

[X]

i had those before. used it on my coupe, was pretty good

[WRXONP]

tuning a car for a exhaust / intake is a bit of a myth also if car is running a maf - maf powered cars basically run off a LOAD vs RPM table - so with intake and exhaust mods - at a givin RPM it will be in a higher cell for the LOAD factor - basically as long as your not pegging the MAF - its fine

if cars running a MAP instead of MAF thats completely different as it runs off MAP (manifold absolute pressure) vs RPM - change something on a MAP powered car - and it will straight away effect the AFR

the only real difference in the ecus is the ignition table - more aggressive timing is basically all thats changed -thats what yields more power- and what comes with more aggressive timing maps??? a higher possibility for detonation - so its a bloody great idea to have the coldest intake charge as possible - so top mount is basically going to cause detonation with high boost

i went from a 6s ecu to a mines 6s - the gains were noticable - had no detonation running 98 and a walbro on 20psi (plus a whole lot of other mods)

theres alot of horror stories out there with these retuned ecus - half of the reason is the fact theyre not supplying enough fuel and intake temps are too high

[Wiretap]

http://translate.google.com/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&u=http%3A%2F%2Fja.wikipedia.org%2Fwiki%2F%25E9%25AB%2598%25E3%2582%25AA%25E3%2582%25AF%25E3%2582%25BF%25E3%2583%25B3%25E4%25BE%25A1%25E3%2582%25AC%25E3%2582%25BD%25E3%2583%25AA%25E3%2583%25B3&act=url

since most of us don't speak japanese.

 

More specifically, (JIS) Japanese Industrial Standards have been established for more than 96 standards that the gasoline octane number in, many of which are commercially available high-octane gasoline actually is 98 - has become a thing of the 100. There was a figure of 100 that has been appended to the name of the product wholesaler in the company of some high-octane gasoline, which was to appeal the octane number was 100 ( below reference).

Also, with regards to tuning MAF based cars, it's true you can't tune fuel however a more free exhaust and intake will permit more timing without det.

[WRXONP]

you cant tune fuel? whaaaaaa??

a fuel table is exactly that - a table with RPM accros and load going upwards - think of it like a spread sheet - because at xxxx rpm u can have a different maf signal (different load) - each cell is tunable - change the spark timing - injector duty (puting it very simple here)

but realistically (when talking tuned factory ecus) - if the injectors and maf are the stock items - the fuel table doesnt need touching - change the injectors and or maf and the table does need tweeking

i beleive the tuned ver 3-4 subaru ecus are daughter boards - just like how u tune a SR20 ecu - where as r32 RB ecus and ver 1-2 / bc5a run eprom which are also tunable

[Wiretap]

I phrased it wrong, I apologise. What I mean is that you're not directly affecting the injector DC, as you have a target AFR upon which the ECU does a whole bunch of calculations to determine the duty cycle.

Unlike a MAP based ECU where you're essentially setting the duty cycle itself (via assumed Volumetric Efficiency).

I apologise that I'm not doing the best job of explaining myself tonight, been a bit of a long day. But I do know the difference or my cars wouldn't be running so well right now

With regards to Subaru chipping, they are daughter boards in the earlier (non-flashable) ones because the 27C256 is a pain in the butt to get hold of these days. Later ones you're lucky if you get a sticker to say they've been reflashed.

[WRXONP]

only ver 7 + have a target air fuel ratio as they are the only ones to have a wideband input into the ecu

anything pre ver7 - the fueling needs to be done by tuner per cell -

[Wiretap]

 WRXONP said:

only ver 7 + have a target air fuel ratio as they are the only ones to have a wideband input into the ecu

anything pre ver7 - the fueling needs to be done by tuner per cell -

They still use the same system except the earlier ones don't have the ability to make large scale stored corrections. (MAF-scaling tuning). The wideband is only used for this and ceases to function reliably once manifold pressure rises (relocating it to the downpipe resolves this but they're still not reliable below 11.5 AFR).

In essence, yes the systems differ for Denso and JECS ECUs, however the same basic principle still applies. However, if you change the intake or exhaust it does introduce MAF error, usually small and this is mostly what the reflashed or chipped ECUs correct. (done by adjusting the MAF calibration table)

[WRXONP]

how can the ecu work off a "target AFR" without a wideband input - it cant

[Wiretap]

 WRXONP said:

how can the ecu work off a "target AFR" without a wideband input - it cant

Quite easily. It knows how big the injectors are, It knows the mass of air entering the engine. From this it can calculate roughly how much fuel it needs to inject to meet the target AFR. During open loop mode it uses this guesstimate and runs with it, during closed loop mode it simply relies on the narrowband to obtain a stoich AFR. It's a much simpler system but it worked pretty well for years.

[WRXONP]

guesstimate - not something i would like controlling my car thats for sure

[Wiretap]

 WRXONP said:

guesstimate - not something i would like controlling my car thats for sure

Something that does control your car if you've got the factory ECU in that S14. Hell, something that controls basically all MAF sensored cars. Unless you've done some pretty solid modifications, that guesstimate is likely to be no more than about 3% off..

[WRXONP]

have watched RB and SR ecus get tuned - no guesstimate that i have seen ???

load vs RPM table - ignition map - and other things such as acceleration enrichment - 5th gear enrichment - cold start enrichment - knock maps to name a few

when driving and watching the table - u see it jumping between cells (RPM VS LOAD)

there was no telling it "I WANT xx.x AIR FUEL RATIO" - it was purely changing cells and watching everything via wideband and consult port (logging it too)

this is sooo far off topic LOL

DeRp

[Wiretap]

Off topic you may be, but I think we're actually in agreement here however you're just looking at it the wrong way. Certainly it's still a load vs RPM table. I don't have any early ROMs to look at here but I could show you what the open loop fuelling table looks like on a GD.

You can definitely tune an individual car better than the 'cookie cutter' factory map through this method, but in reality unless you're changing the intended AFR (not target value, this is a theoretical one we're talking about) all you're doing is compensating for MAF sensor error.

Also, there's no way the ECU could work off wideband at high loads for one simple reason: there's a 100ms ish delay between combustion and the measurement by the wideband, you'd be forever oscillating about the target value. Direct Injection is a system that aims to resolve this but it isn't so refined yet.

[WRXONP]

i was told by someone that it is used for open loop fueling? does it just log it ? and not adjust in real time?