Recently did a basic chip analysis for someone which highlights the issues of running unknown chips in UK Zeds.

 

The comparative map is 41P13 JDM Auto upon which the modified map is based on.

 

Fuelling & Timing Differences:

 

 

Fuelling is pulled in a very basic manner. One thing that the tune does have going for it is the fact the final load column is actually increased to compensate for the additonal air flow (load) caused by increasing the boost levels. Unlike the JWT chips.

 

Timing is advanced in an equally simplistic way. Typically +4° advanced at high load & +5 or +6° advanced in the transitional region (coming onto boost where knock is most likely to happen).

 

 

Fuelling & Timing Values:

 

 

The timing map is the one of interest here as the fuelling values are arbitrary in the above image. 28° on full boost at 4400RPM. That's race fuel territory if you want your pistons to survive. Thankfully the VG30DETT is incredibly strong and resists knock well (check out a Rover T16 engine for the opposite end of the scale), but the cumulative damage will take its toll eventually. Sooner rather than later if used in anger on a regular basis.

 

 

Timing Knock/Safety Map & RPM Limits:

 

 

The safety map is identical to the normal timing map, so when knock is detected in the knock-enabled regions, the timing remains unaltered whereas with OEM tunes, the timing is retarded to protect the engine. Fuelling safety map is unaltered from OEM, thankfully. Not a problem if the map was suitable for UK fuels in the first place, as it wouldn't detonate if tuned correctly.

 

RPM Limit of 10,000. Nothing more really needs to be said about this.

 

This is very similar to the Central20 ECU map I've analysed in the past. They would have been programmed a long time ago when technology was relatively limited for aftermarket tuning. Also, very important to note is that the timing on the JDM 41P13 map is already borderline for use with UK fuels.

And this is the biggest reason the likes of me who knows jack all, and so many others are commkng to you for guiddence and advice.and with your help yourll have a generation of reliable tunned zeds.

Not got a clue what I'm looking at. When I looked at your laptop all I could see was numbers and pritty colours lol.

 

Hopefully this will be the end of dodgy mapped zeds. Mine is amazing now and every other one should be there is no excuse

And it will soon pay for itself in mpg.

 

Keep up the awesome work mate :pint:

good of you to share that Noel

Mines going for some TLC with Lee Dent than ill be over to yours NOZ for sure

Very interesting. I was always interested in what the older more generic setups were like. I have quite an early 'known' chip in my car and next year when the weather becomes better and after I've fitted a new loom, would love to get it mapped correctly.

Noz,

 

there has been mention of piggy back and stand alone ECU's and you've given your professional opinion on them. I was on Z1 last night just looking at engine rebuild bits and came across this one.

 

http://www.z1motorsports.com/product_info.php?products_id=6749{605}2906

 

what would be your views on this?

 

im aiming for between 450 and 500 horses.

 

would my cash be better spent on something else and getting you to do a chip for the car rather than rewriting this one?

 

CheerZ

 

Neil

The central 20 mapping is clearly not up to date but more essentially was designed for use in Japan where 100+ ron fuel is normal, also the mapping on that and similar Japanese spec eproms was designed around particular use in Japan and their road / traffic conditions and of a certain technology and customer expectations, the use of the word "generic" is a poor general term as the mapping was once done for a specific set of requirements. ( albeit outdated now)

 

Other more UK based eprom mapping has been developed from other set ups like the US JWT and has been updated slightly over the years to better suit UK requirements this has become such a widely used and proven eprom now the term copy is more fitting in my view, of course any custom mapping to a particular vehicle is always considered the most effective was to go especially given today`s owners higher expectations.

 

Jeff TT

Darkside - unless you've stripped the car of most oem electrical subsystems or want to drive things like a digi dash, I'd stick to the OEM ECU, it's very good

Noz,

 

there has been mention of piggy back and stand alone ECU's and you've given your professional opinion on them. I was on Z1 last night just looking at engine rebuild bits and came across this one.

 

http://www.z1motorsports.com/product_info.php?products_id=6749{605}2906

 

what would be your views on this?

 

im aiming for between 450 and 500 horses.

 

would my cash be better spent on something else and getting you to do a chip for the car rather than rewriting this one?

 

CheerZ

 

Neil

 

That would be quite a hefty bill once it lands on these shores! Top of the range Link G4 is around £1200 tops. But, as already mentioned, for 450-500 horses and non-motorsport applications, the OEM system more than adequate. It is fully mappable within certain constraints, with launch control even being possible on some models (similar to the Mitsubishi Evo ECUs).

The central 20 mapping is clearly not up to date but more essentially was designed for use in Japan where 100+ ron fuel is normal, also the mapping on that and similar Japanese spec eproms was designed around particular use in Japan and their road / traffic conditions and of a certain technology and customer expectations, the use of the word "generic" is a poor general term as the mapping was once done for a specific set of requirements. ( albeit outdated now)

 

Other more UK based eprom mapping has been developed from other set ups like the US JWT and has been updated slightly over the years to better suit UK requirements this has become such a widely used and proven eprom now the term copy is more fitting in my view, of course any custom mapping to a particular vehicle is always considered the most effective was to go especially given today`s owners higher expectations.

 

Jeff TT

 

The problem is, that they were never properly mapped in the first place, the bins were edited in a rudimentary fashion using hex editors once the files had been disassembled, hence the blanket addition/subtraction of fuelling & timing. It wasn't a case of road / traffic conditions, it was simply that the technology wasn't there. Regardless of traffic, there are optimum settings for a fuel & timing map for each specific car as you point out, but there are also close to optimum settings suitabvle for a generic chip. This can only be found by using current technology with real-time systems and a great deal of dyno time.

 

Back in the day (circa. 2003) when I was at the mercy of having to use chips for my S13 that melted spark plugs, I decided to do it myself. When I started out I had to modify hex values directly, burn a chip, fit the chip, go for a run up the road, monitor fuelling & knock, stop, make necessary alterations, rinse & repeat. It wasn't possible to do it in real-time and a map would typically take a few days and even then, the results were poor compared to when I first fitted NIStune in 2008 and after just one day, hit 382bhp after the boys at MGT kindly let me have a play at an SXOC RR day (they couldn't believe the results for a 1809cc engine). I wouldn't have even got close doing it the old-fashioned way. Just too difficult.

 

The JWT map isn't actually mapped for any extra boost over the stock maps, the fuelling & timing values are simply continued from the final column. It is based on the OEM 47P10 Manual Transmission (no AIV) file.

 

Next post will be a full comparison of the JWT map and the OEM 47P10_MT file.

Nos, I wonder if you could give your expert opinion on this post I came across on TT.net a while back. The post refers to

an article in a 1990 edition of Turbo Magazine on work HKS did tuning a 300ZX.

 

http://www.twinturbo.net/net/viewmsg.aspx?forum=main&msg_id=23596

 

The key bit being "When HKS tested the stock car's fuel system they found that a correct air/fuel ratio can be measured

all the way to 16 psi without modification."

 

I've always wondered how this was possible.

 

-Andrew

JWT Chip vs OEM 47P10 (USDM). The JWT chip is based on the 47P10 USDM map, not the EDM (European Domestic Market) specifically tuned by Nissan for European (inc UK) fuels.... See Pics 3. & 4. below. The following loooooong post is how I typically do a very basic map analysis.

 

Fuelling & Timing Differences:

 

 

As can be seen, the percentage of the fuelling & timing maps that differ from one another isn't great. The top map is the fuelling, and for some reason the majority of the work has gone into the high RPM light load areas, typically where an engine rarely operates either day-to-day or on track Load points 8-56). Fuel has been added top end (top-right corner).

 

The bottom map is the timing, which is where you feel the difference during 99% of normal engine operation. In the case of the JWT chip, it remains unaltered for the most part from the stock US map, so off boost the car feels exactly the same as standard. The problem is, because the load points (scale along the top, can be thought of as 'boost') is the same as stock, in load columns 72, 80, 88 & 96, there is less timing, so at stock boost you will actually produce LESS power. Only when the boost is increased past the maximum load value of 96 does the reduced timing keep everything together. This would never be mapped like this in realtime as you are able to see what the maximum load value is, and the only benefits power-wise you are getting here is from the increased boost. OEM Load (boost) cut is increased, but the OEM is set at a value of 128 (higher than 88 & 96 mapped values for fuel & timing) so moot anyway. A decent boosting car hits 120

 

 

Scaling & RPM Limit:

 

 

The above graph shows that the maximum load scale for both JWT and stock chip is exactly the same for the fuelling maps (value = 88). It is the same for the timing maps as well (value = 96). The RPM limit is increased from 7000 stock to 7200 RPM. The good thing about the JWT map is that the RPM scale is extended from 6400 to 6800 RPM, although still short of the 7200 RPM limit. This is one parameter that was porrly programmed in the OEM map (mapped to 6400 RPM with a 7000 RPM limit). Most likely to increase resolution and therefore drivability where the engine spends more time.

 

 

USDM Vs JDM:

 

 

As is plainly evident, there isn't a great deal of difference between the USDM & JDM OEM maps. Fuelling is exactly the same, timing is reduced slightly in a few places at maximum torque as this is where knock can be a problem. Note that these areas are above the knock-enabled feedback section.

 

 

USDM Vs EDM / UK:

 

 

Here we see the main issue: The difference between maps based on USDM / JDM spec cars and UK Zeds. Same goes for all grey imports, Nissan reduced timing and added fuelling at high load & transitional regions for the EDM 300ZX, Pulsar, S13, S14 et al to make them safe with 95 RON fuel. The cruise & low boost section are exactly the same, however. This is where a good generic chip will make the most of the 99 RON fuel by working with this section to improve off boost performance & fuel consumption, which is where 99% of cars spend 99% of their time.

 

It can be argued that there are no doubt countless JWT-powered Zeds out there running fine, and I am definitely not disputing this. However, times have moved on with the advent of OEM-based live tuning options and standalone engine management and the job can be done properly. It wasn't long ago I was arguing with people regarding the perceived power abilities of the VG30DETT engine and stock components. I had all this data available then (I have done for about 5 years), but I wanted to let my own car & work do the talking rather than slate the 'opposition' so to speak :D

 

The JWT chip is fine for its purpose (basic way to allow more boost using 98-99 RON fuel) but given that it's 90% just a stock chip, it simply doesn't do the Zed justice and the only extra power & torque is from the additional boost, nothing else. Drivability on the whole is unchanged, you simply lose a section of O2 feedback meaning it runs pointlessly rich above 2500 RPM when cruising. This is because it uses the High Gear fuel map 100% of the time, regardless of gear. I will say one thing, however... It is a lot better than the various 555 / 740 / 850 chips I've come across over the years.

 

Please note I am not putting down anybody for using or selling the chips, and I really don't need to put down others to big myself up. There are also many other options for getting your car mapped, not just myself. I'm simply reporting the facts finally, when hopefully no one thinks I'm biased or trying to brainwash anyone.

 

Look into my eyes, into my eyes, not around the eyes but into my eyes. You're under.

Edited October 25, 201312 yr by Noz
Inserting correct image

Nos, I wonder if you could give your expert opinion on this post I came across on TT.net a while back. The post refers to

an article in a 1990 edition of Turbo Magazine on work HKS did tuning a 300ZX.

 

http://www.twinturbo.net/net/viewmsg.aspx?forum=main&msg_id=23596

 

The key bit being "When HKS tested the stock car's fuel system they found that a correct air/fuel ratio can be measured

all the way to 16 psi without modification."

 

I've always wondered how this was possible.

 

-Andrew

 

The stock maps run very rich. They're not as bad as Toyotas, but typically you see mid 10s AFR at high load. This gives plenty of room to increase the boost past the maximum load level of 88 without it running lean.

 

At Load = 88, the estimated injector pulsewidth on the stock 47P10 fuel map is between 14ms at 3600rpm and 16ms at 6400rpm. This typically corresponds with an AFR of 10.6-10.8:1 (rich). Now, when boost is increased past this maximum level, the pulsewidths remain the same (14-16ms). More air is going in, but the fuel remains the same, hence it results in a more lean condition. This is fine up to a point, typically 12:1 AFR.

 

The problem is that the timing also follows the same protocol, but luckily was programmed up to a maximum load of 96 (often Nissan did this). So, the timing is pegged at 20-22° BTDC, when it should be retarded due to the increase in load & intake temperature. Naturally, correct modifications can help here such as FMICs.

 

The Toyota MR2 Turbo runs so rich (low 10s on boost) as standard, I was able to run 1.4 bar on the stock turbo & ECU after retarding the base timing and it sat at a nice 11.5 AFR.

I know this is an old post but I would like to ask noël if he has ever compared the z32 mines ecu or impul ecu? I have both and wondered if they are any good.

Noël is my French cousin :laugh:

 

I've got the Mine's & Impul maps somewhere. They'll both be your typical Jap spec maps (advanced). Jimmer @ Power Zed has a nice pic of an engine running a Mine's ECU....

 

Same as with any ECU upgrade that hasn't been proven in the UK or wasn't even destined to be used in this country, both AFR & knock should be monitored. You can never be 100% sure what's been programmed onto the chip without analysing the maps, either.

 

I think the ECU in the first post that I analysed for someone was actually fitted by them (nothing to do with me whatsoever). It was run at 22psi and subsequently destroyed the engine. Car is being broken for spares. You've gotta laugh...

Noel, I have seen bits of info on your own choice on plugs, but would you be able to write a definitive post on these? I understand that spark plug technology has advanced enough whereby the recommended NGK plugs that Nissan advise are no longer as suitable as some new iridium plugs, but I would really like to learn more on this for my own plug selection before I take it to you for mapping at some point next year.

 

Z1 SMICs are going in shortly, along with a brand new OEM engine harness, I'd like to get the best possible signals and spark moving forward.

 

Cheers

http://pages.ebay.com/link/?nav=item.view&alt=web&id=290770994364

 

Or

 

http://pages.ebay.com/link/?nav=item.view&alt=web&id=230847958113

 

:)

Edited October 17, 201411 yr by Joely P

Noel, I have seen bits of info on your own choice on plugs, but would you be able to write a definitive post on these? I understand that spark plug technology has advanced enough whereby the recommended NGK plugs that Nissan advise are no longer as suitable as some new iridium plugs, but I would really like to learn more on this for my own plug selection before I take it to you for mapping at some point next year.

 

Z1 SMICs are going in shortly, along with a brand new OEM engine harness, I'd like to get the best possible signals and spark moving forward.

 

Cheers

 

This is a good thread from 2 years ago where there is a solid debate between RobH & myself about spark plugs. He approaches it from the "Manufacturer is always right" point of view, as he's a spark plug dealer. Me, from a tuner's point of view. Both valid approaches.

 

I've not gone through the posts I made back then, so some may be due for updating based on 24 months of subsequent experience :laugh:

Gobbledegook. Pure and simple. You could have posted a picture of a giraffe on a bike reading hamlet dressed as Maggie Thatcher and it would have made more sense.

 

I am glad people like you exist, to make my cars faster safely.

Link might help.....

 

http://www.300zx.co.uk/forums/showthread.php?165254