Just to start with can we stick to combined pressure or it just gets confusing.

 

So is 20-22psi ok on stock setup?

 

Because in a few weeks that's what I'll have. I've done my research and most say that after 28psi you need to seriously start thinking about internals.

 

So I thought a 3-4 psi increase each turbo wasn't over the top. But should give me that little extra kick. And I was just wondering what other people where running.

 

Before anyone asks one of my turbos is shot and while I was changing them I thought I might as well do a few mods and get a little more power.

 

I should be getting 400bhp @ flywheel at this pressure . . . if my maths is right :tongue_smilie:

Any updates on what the outcome of this was?

Yes I'll admit its rare, but I'm happy with just uprating the actuators and I can add one later.

 

Also there not the cheapest and I know people with them and they just end up turning them up and up, getting the bug and wanting more power.

 

May not break the car but it just adds more wear which I want to avoid, hence only a marginal increase that I was looking for.

 

So in conclusion . . . it appears I'm going to be running about 12psi. Which from what other people say there running or have run is not all that extreme - denfinatly won't "let him blow his engine up and then he will know your all correct":

 

"MarkDerby - with a remap u can up the boost to 13/14psi ish",

"bigh - I was running 14 psi with boost jets and upgraded chip, on the dyno it maxed out at 370bhp"

"vodkashots - 14 to 16 on stock is what ive heard countless times."

"Yowser - With a remapped ECU , 14psi is a safe maximum raised boost level with Stock Injectors."

"jaylox - i used to run 16psi boost on stock tubs, remapped ecu"

"z32bolt - you could run a max of 16 psi on stock injectors and a chipped ecu"

 

So thanks for all the info guys, it's kind of put my mind at rest.

 

I'm starting the turbo swap on Tuesday so nice to know I'm not going to spend however long and it all be for nothing. :blush:

 

All those estimations are too low if everything is in good working order and the engine isn't a ticking time bomb.

 

VG30DETT: Criminally-underrated & never trusted.....

All those estimations are too low if everything is in good working order and the engine isn't a ticking time bomb.

 

VG30DETT: Criminally-underrated & never trusted.....

 

when im not obsenly poor me and you are going to have to to talk about squeezing the magic 400 hp outta my car. lol

All those estimations are too low if everything is in good working order and the engine isn't a ticking time bomb.

 

VG30DETT: Criminally-underrated & never trusted.....

 

Those are safe levels that provide a very noticeable power gain for your typical owner without access to a Air/Fuel ratio gauge and a keen ear for detonation on a 20yr old car, using an off-the shelf recomended ECU upgrade. Owners should always ensure the car is in healthy order before undertaking any increases in boost pressure.

Edited January 3, 201312 yr by Yowser

when im not obsenly poor me and you are going to have to to talk about squeezing the magic 400 hp outta my car. lol

 

Look forward to it :thumbup1:

Those are safe levels that provide a very noticeable power gain for your typical owner without access to a Air/Fuel ratio gauge and a keen ear for detonation on a 20yr old car, using an off-the shelf recomended ECU upgrade. Owners should always ensure the car is in healthy order before undertaking any increases in boost pressure.

 

Yes, but things have moved on a bit now, so those levels are not really relevant. Every 20yr old turbocharged car should have an AFR gauge, it's the best indication to a typical owner that something is going wrong before it goes really wrong. If you're driving a 300bhp turbocharged car as complex & difficult to work on as the Zed, in this day & age you're a fool not to take the appropriate measures to ensure things don't go awry too easily. This means an AFR gauge and knowing what det sounds like, even on a standard car.

 

Comparing the engines of two similar cars: Everyone speaks of the 2JZ as the Holy Grail of 6 cyl engines, whereas the VG is dismissed with an appalling reputation for reliability. The reason these preconceptions have come about is that with the Supra, there were no options for advanced ECU tuning other than piggybacks. Therefore, everyone had to go standalone (apart from some very clever, very secretive bods in Japan). With this comes big costs and typically necessitates a full setup & bespoke map by someone that knows what they're doing. However, from day one Joe Bloggs could reprogram his Z32 ECU, hence there are some truly dire 'tunes' out there, accompanied by countless melted pistons no doubt. Pistons don't melt because of 17psi from stock turbos. These aren't Rovers.

 

I have removed chips from Z32 ECUs with no rev limit. Or how about a blanket increase of 10° across the entire JDM timing map, which is already too advanced in places for the UK (pre-99 RON days). I have a well-known '555' map which is about 2 mins of adjustment away from the freely-available '555Z' map, and in one essential part, actually worse and verging on dangerous. One day I will post images of all the maps I have acquired over the years :blink:

 

I dont know where to start here....

 

Do not run more than 12psi on the Stock ECU, the mapping is not there for extended boost and you can all sorts of fueling issues. With a remapped ECU , 14psi is a safe maximum raised boost level with Stock Injectors. Beyond this and the Injectors are at 100% duty for extended periods and the the mixture leans out, resulting in increased detonation issues.

 

With larger injectors (and a remap to suit) and aftermarket Intercoolers you can run them up to 17/18psi before they make too much heat to be efficient. However they wont last long and neither will a 20year old stock engine.

 

Beyond 14psi on stock turbos, most will opt to then go for an aftermarket turbo setup, and since the engine is coming out at this point it makes sense to fit Forged pistons, new bearings and freshen up the rest of the engine. This is where it starts to get expensive.

 

With regards to the mapping above 12psi on the stock ECU, a well-known chip that works with mig tips & 15psi is exactly the same as the stock OEM chip. The fueling map ends at a load value of 88, timing at 96. I've posted about this on another thread.

 

Beyond 14psi, injectors are not at 100% duty. Nowhere near in fact. I posted a log of fueling at 21psi on Auto turbos, filters & backboxes. It is a specific parameter in the ECU programming that causes a lean condition at 1.2-1.3bar and 3200-4800 RPM. You don't need larger injectors for 17/18psi, either. Or 21 psi....

 

The stock turbos are good for a lot more power than given credit for, if you know what you're doing. Here is an extreme example, ignoring the USA bhp inflation: http://specialtyz.com/blog/?p=441. To suggest that beyond 14psi you need to look into bigger turbos and may as well drop a few grand on a forged build is simply not the way it needs to be, when there are in fact plenty of options available.

 

A 3L twin turbo V6 with forged rods from the factory pushing out 280+bhp with restrictive exhaust, manifolds, intake, miniscule turbos and SMICs and a less-than-ideal ECU map is not going to struggle at 500bhp with the appropriate parts and tuning methods. No different to the 2JZ. It's kind of odd that so many owners believe that VG30DETTs are fragile, when in fact they are Nissan's crowning glory from the 80s & 90s.

 

The UK Zed tuning scene is such a long way behind everywhere else, still at the mercy of 10yr old generic maps that weren't much cop a decade ago. Thank God for JD, otherwise it would be even worse off :ph34r:

 

A good friend of mine is looking to buy a Zed having come from a 540bhp Nissan S14. This sums things up pretty well:

 

P.s

Tell me about your zed experience , are all the horror stories true?

 

the owners club is weird tho they all seem to say it will blow up over 350bhp an will only last 3 months if that!!! yet the US and OZ guys seem to say the stock block can handle 700 ok

 

Similar response to him and this thread: For the last 13 months, 17-21 psi, 380-394bhp, 380-410lbft & 13.1@110mph with stock injectors, stock turbos, stock SMICs on my daily driver, dragged regularly.

Edited January 3, 201312 yr by Noz

I'm glad somebody in the UK is pushing the Z tuning. Its good to see. Its Interesting to read about your experiences with the stock fuel system, the leaning out that is often seen at higher boost levels has long been perceived to be a injector duty issue and its great to see that somebody has possibly identified it as a mapping issue and overcome it.

 

I'm completely with you in regards to Z engine strength, they have a poor reputation that is undeserved, and there is on only one UK ECU mapper I've ever recommend in the past (JD).

 

To be clear though, there are issues with leaning out at higher boost levels with the ECU remaps that are readily available to the Z community. A lot of us push it higher than these limits, we have AFR gauges and are prepared for the outcomes, but that doesn't mean we'd recommend the same to everyone else.

 

Have to bear in mind though that if people read on a forum that they can run 21psi...they'll go straight out and wind the thing up to 25psi and then when it all goes wrong they talk shit about how unreliable Z's are and blame those that told them it was ok. There are precautions to take, and the off-the-shelf ECU remaps readily available are not setup to cater for such extreme levels.

Edited January 3, 201312 yr by Yowser

I'm glad somebody in the UK is pushing the Z tuning. Its good to see. Its Interesting to read about your experiences with the stock fuel system, the leaning out that is often seen at higher boost levels has long been perceived to be a injector duty issue and its great to see that somebody has possibly identified it as a mapping issue and overcome it.

 

I'm completely with you in regards to Z engine strength, they have a poor reputation that is undeserved, and there is on only one UK ECU mapper I've ever recommend in the past (JD).

 

To be clear though, there are issues with leaning out at higher boost levels with the ECU remaps that are readily available to the Z community. A lot of us push it higher than these limits, we have AFR gauges and are prepared for the outcomes, but that doesn't mean we'd recommend the same to everyone else.

 

Have to bear in mind though that if people read on a forum that they can run 21psi...they'll go straight out and wind the thing up to 25psi and then when it all goes wrong they talk shit about how unreliable Z's are and blame those that told them it was ok. There are precautions to take, and the off-the-shelf ECU remaps readily available are not setup to cater for such extreme levels.

 

Leaning out is definitely not an injector duty issue. A 370cc injector flows enough fuel to support circa. 70-75bhp at the limit. Some chips do have suitable programming in this respect, others don't. It's a parameter that any self-respecting mapper or chip tuner should be aware of.

 

I don't think that Zs could get a worse reputation than they already do to be fair, one that is perpetuated by misunderstanding. The fact is, with appropriate tuning you can run 21 psi on stock turbos without leaning out, it's not even a grey area, it's just fact based on injector size, mass flow rate and of course, empirical evidence. It's no different to working within constraints with any other vehicle. I'm not the first to do this by any means, just the first to post about it at length on this forum, I guess. The knowledge has been out there for a long time, which is why threads like these are quite a surprise.

 

I 100% agree that there will be issues with leaning out with some well-known chips (it's best to differentiate between generic "chips" and "remapped ECU"). I would be wary of allowing someone to run 21 psi on my own proven maps, you have to cater for the worst-case scenario which includes user error (95RON fuel, incorrectly-set base timing, upping the boost "just a bit more" etc). But, the Zed is no different to the R32, 200sx, Evo, Cosworth etc. Full remaps & standalone options ARE readily available to the Z community, and have been for years. There really is no logical reason why it's not commonplace already.

 

I guess there could be a more realistic balance portrayed between caution and experimentation, which only comes with a better understanding of why an engine may have gone west in the first place. For years I extolled the virtues of the much-maligned CA18DET. Go on the SXOC and ask what a stock CA is good for and chances are someone will say "Noz ran silly power, over 400bhp with a massive Chinese turbo". The long-held belief before this was that the rods gave up at 350bhp, due to a bent rod happening at this power level and someone stating this as fact. Trouble is, the car was running a 5th injector, it was a fluke it lasted as long as it did. I am very proud of what I did with my old S13 and amazing CA :biggrin:

 

The only thing extreme about running 21 psi is the amount of boost you're pushing through those puny turbos. To be fair, they don't hold 21 psi for very long, at the red line it's down to about a bar with minimal breathing modifications. I've definitely not pushed anything other than the turbos themselves, my main Zed is a daily that needs to be reliable 100% of the time. I would be more than happy to run twin S200s or Holset HX30s on a stock bottom end though. A set of ACL shells and the coolant passages fettled would be all it requires. Delete all the acronyms, remove all the restrictions. Massive intercooler(s), minimal intake pipework (2.5"), exhaust, manifolds, throttle bodies etc. A decent VG will probably run 330-340bhp in an unrestricted state at stock boost levels. All it would take would be two nicely-sized turbos to hit a relatively reliable 85bhp per cylinder with low intake temps. Cast pistons won't be troubled at that. Comparable to a 340bhp 2L, 500+bhp all day long....

I have to say chaps that this is a thoroughly interesting read. Great thread. Been following it all along with interest and hopefully learning something along the way. Although my memory is shocking!!

Its a refreshing change to start discussing this sort of topic and from what ime reading Noel could start putting our cars back on the (excuse the pun) map with respect of reliable power gains :thumbup1:. Very intresting posts too from Dave (Yowser):thumbup1:

If a Zed is running an EBC can you still make use of the stock knock sensor to either alert you to knock or reduce boost like the standard system or do you have to map it taking into account conditions that may occur and make it more likely, like hot weather?

Leaving the stock boost solenoids connected will give you a reduction in boost if det occurs as well as retarting the ignition so good to keep them in place.

 

Jeff TT

If a Zed is running an EBC can you still make use of the stock knock sensor to either alert you to knock or reduce boost like the standard system or do you have to map it taking into account conditions that may occur and make it more likely, like hot weather?

 

It's best to forget about the standard knock sensor, it's fairly useless. With an EBC, the stock safety boost solenoids are redundant although the ECU will still access the knock maps.

 

With a hot-wire MAF system, there isn't any need to compensate for intake air temps (IAT), unlike MAP based Speed-Density systems (eg aftermarket EMS & Cossies) or flap-type AFMs (eg MR2 rev1 & 2). If temp increases, then air density decreases for a constant volume (density = m/V = PM/RT) and the MAF output voltage is lower accordingly. At high altitudes where pressure is lower, density will be decreased for a constant volume of air and vice versa. Ideally, you want to map a MAF-based vehicle in the coldest conditions it will experience at sea-level, as this will provide the greatest mass of air per unit volume which results in the highest load on the engine and highest MAF output voltage. In practice, you take into account the current conditions and extrapolate as best as possible.

 

For information, here is a stock EDM timing map. The highlighted cells are the ones monitored for knock as standard:

 

 

When the knock sensor sends a signal to the ECU, separate knock maps are accessed (more fuel, less timing) as well as safety boost. Chances are there isn't much point in extending the knock-monitored regions due to false positives from engine noise. When mapping, I suspend all OEM knock monitoring and use an aftermarket unit and my ears. My old CA used to show knock readings in the hundreds using the stock sensor.

Yes an intresting read from NOZ......also intresting which I did not know untill reading this thread is that NOZ is TURBONOZ the supplier of the chip I purchased on the net mid 2012 and is working great.

Yes an intresting read from NOZ......also intresting which I did not know untill reading this thread is that NOZ is TURBONOZ the supplier of the chip I purchased on the net mid 2012 and is working great.

 

Hello!!

 

I must have sold close to a thousand chips for various makes & models. Lots of Turbonoz Nissan chips all over the world. Very cool :biggrin:

Thanks for the info. At what point do we need to uprate the headgaskets? Can the standard Nissan headgaskets take whatever stock tubs can throw at them?

Edited January 5, 201312 yr by Eggs

Problems youl have with increasing boost over 14psi is injector duty maxing out and the fact that with the small standard turbo's, as boost is increased so is heat, heat + lean mix = destination = ****ed piston land rings.

 

The standard turbo's will produce more than 14psi but you need to keep charge temps down and keep fuelling adequate, plus dont forget those 15-20 year old turbo's reliability will decrease as you ask more from them

Detonation*

Please read the thread and some of my previous posts for some interesting facts for you. Injector duty is fine up to & over 21psi on Auto turbos. Dead ringlands are due to poor mapping.

 

Eggs, stock HGs are fine for big power.

Please read the thread and some of my previous posts for some interesting facts for you. Injector duty is fine up to & over 21psi on Auto turbos. Dead ringlands are due to poor mapping.

 

Eggs, stock HGs are fine for big power.

 

Dude stock tubs dont run 21psi,i dont care what your claiming in aint happening,heat soak and impeller size permits this,its not possible.Im running gt525 turbos which run the largest impeller you can fit in stock housing and 18psi they flatline.Ive seen it on the dyno during mapping you can crank the gain etc to what you like they wont produce past that limit.Im open to new stuff but this is frankly hilarious.Flame me if you like but ive fitted many hybrid turbos and know what they can produce.If you wanna shit and call it chocolate carry on,And nobody runs stock headgaskets for big power,ask kyle puckett for a 500hp engine and see what gaskets it comes with.

Edited January 5, 201312 yr by jimmer

Please read the thread and some of my previous posts for some interesting facts for you. Injector duty is fine up to & over 21psi on Auto turbos. Dead ringlands are due to poor mapping.

 

Eggs, stock HGs are fine for big power.

 

Well 15psi on a boot to the floor run ****ed my ring lands and my dat slogger shows injector duty at 100% before I'm ready to change gear!! Hence why i aint refitted a boost controller after the last one died :)

 

- - - Updated - - -

 

Data logger*

Dude stock tubs dont run 21psi,i dont care what your claiming in aint happening,heat soak and impeller size permits this,its not possible.Im running gt525 turbos which run the largest impeller you can fit in stock housing and 18psi they flatline.Ive seen it on the dyno during mapping you can crank the gain etc to what you like they wont produce past that limit.Im open to new stuff but this is frankly hilarious.Flame me if you like but ive fitted many hybrid turbos and know what they can produce.If you wanna shit and call it chocolate carry on,And nobody runs stock headgaskets for big power,ask kyle puckett for a 500hp engine and see what gaskets it comes with.

 

Pop down to the dyno at any time, and see for yourself :) Bring your car along to Santa Pod, and see for yourself :)

 

Before I respond to your post, let me suggest something regarding the highlighted sections. We're both traders on here, if you're going to question one of my posts, can you keep it respectful please? Let's just keep things technical and in perspective. That kind of rant is for the schoolyard and really doesn't prove or disprove anything, the only one "flaming" is you, I'm afraid.

 

Have a look around the internet for examples of people running 21psi on stock turbos. This is quite funny, because I'm not the only one. Not by a long shot :laugh::laugh:

 

Here's a quick one from my thread here: http://www.300zx.co.uk/forums/showthread.php?165369-Running-1-4-bar-%2821psi%29-on-stock-injectors&highlight=

 

We had a customer once who was running 21psi in a daily driver, bog standard engine, we checked all we could get to and nothing looked or appeared to be upgraded, the car went like a super missile and had no sign of detonation and seemed to lap up the boost No problem, I drove that particular car several times and could not work out how it was running how it did.

 

Later the owner had a small problem and posted up on here how it was running and was blasted for been incorrect and no one believed him, but we had seen it and it was real, a garage owner in Cyprus also came on here years ago and said how they had 500bhp out of a totally standard engine and no one trusted what he said, later on a trip to Cyprus I saw how it was done and its very possible.

 

Jeff TT

 

At no point have I said that stock turbos run 21 psi to the limit. That is never going to happen, they are tiny. They hit 1.4 bar with ease in the mid range, tailing off to a bar maximum on my car, how else do you think I made 410lbft with just filters and back boxes, or do you think I'm fudging results? How did I hit 110mph in 13.17s with just filters & back boxes on 225/55 tyres with a 2.3s 60ft without running a lot of boost on the stock turbos with Tesco Momentum 99 RON? I've asked you this before on another thread where you basically accuse me of "talking shit", and you didn't answer then. Maybe you can answer it now? Also.... Feel free to come and inspect my car whenever you wish. You can drive it yourself. It will be at Pod most weekends after January 21st, you can take it up the strip. Anyone is welcome to test drive my car if they don't believe all the actual evidence I post. It is a daily-driven development vehicle, specifically for this very purpose.

 

I hope you will take me up on one of my offers. I have no reason to lie. Everything I have done with my car, can be done by anyone. Well, apart from the mapping of course :whistling:

 

If your turbos are only hitting a maximum of 18psi, then I'm afraid that is your issue, and not indicative of the turbos in general. Why crank the gain? It's a pulsewidth-controlled solenoid, you increase the duty cycle to set the peak boost level, the gain controls the the rate at which it hits said peak via feedback. Seriously, if your turbos can only physically produce 18psi, then something is clearly not right. Are you telling me that if you disconnect the actuator lines, they are pegged at 18psi?

 

Here, have some evidence that the issue lies with YOUR turbos or set up:

http://specialtyz.com/blog/?p=1269

 

 

I'm surprised someone that has "fitted many hybrid turbos and know what they can produce" would actually believe that any turbo is simply going to "flatline" at 18psi with no boost regulation. Very surprised. How come this hasn't been investigated and rectified? 18psi = 1.22 bar. People run that all day long on T25-type turbos. I ran 17-18psi on a stock T25 for a year, 22psi on a stock T28 for many months before it gave up. I have never understood why people claim that because something of theirs couldn't do something, then that is the way it has got to be. Of course, this works both ways, too! Just because my car runs a 13.1@110mph with filters, backboxes & boost, doesn't mean the next person's is going to...

 

I don't know why all this is so hard to believe:

Stock 1809cc CA18DET: 383bhp & 326lbft at the hubs (circa 420bhp, 233bhp per litre)

Stock 3SGTE: Last season, 1.5 bar on a GReddy T78, 12.39s@113mph (approx 370bhp, 185bhp per litre)

Built SR20DET in my Pulsar: 1.9 bar on a T28, 12.08s@115mph (approx 350bhp, 175bhp per litre)

Stock 3L VG30DETT: 394bhp @ 410lbft, 13.1s@110mph (131 bhp per litre). Nothing special so far, the only thing I'm pushing are the turbos.

 

Slick Pete has seen the Zed in action, pulling consistent 13.1s quarter miles. It is what it is and it does what it does. Nothing more, nothing less :)

 

I have run & tuned so many different vehicles, from Cossies to Fiat Coupes to Rover Turbos. And of course most 90s Nissans. I also know what is possible and what is not. Up the boost on a Rover Turbo, it WILL die. That is FACT, I proved it for myself. Useless cars. People in the UK are too quick to dismiss the figures that our American & Antipodean cousins run that they forget that even if powers are inflated, they still have shown what can be done. Years ago.... This is not the first time I have been called out by an expert in his own particular field, and it won't be the last. Trust me, if I couldn't run 21psi on stock Auto turbos, I sure as Hell wouldn't post on an open forum that I can, not considering all the proof I present to everybody :laugh:

 

Oh, by the way.... SpecialtyZ: 900rwhp with stock head gaskets. Some guy called Russell with 1050-odd rwhp on stock head gaskets. Just extreme examples found on the net. Just because someone supplies something, doesn't mean it's the only way of doing it. There are other factors involved with regards to business.

 

Final point to add: The moment a component fails, I will report about it. I am finding the limits of stock components, just like I have always done. For years.

 

Cheers,

 

Noel :gunsmilie:

Edited January 5, 201312 yr by Noz
Link to GT525 Blog

Well 15psi on a boot to the floor run ****ed my ring lands and my dat slogger shows injector duty at 100% before I'm ready to change gear!! Hence why i aint refitted a boost controller after the last one died :)

 

- - - Updated - - -

 

Data logger*

 

No.

 

It was component failure or improper mapping that destroyed your ring lands. Sorry to say, probably could have been avoided. Your data logger? SAFC2? Consult?

 

Here is some proof, which I have already posted, showing 21psi "on a boot to the floor run":

 

 

Let me break it down:

 

Red line = RPM

Green line = MAF voltage

Blue line = Injection duty cycle

Pink line = AFR

 

As is plain to see, duty cycle at 94% at an RPM of 5937 with an AFR of 11.89:1. I picked the highest duty cycle from the log to highlight. The MAF voltage of 4.574v is indicative of the power I was running. Z32 MAFs have a voltage output range of 0-5v. I will leave it up to you to work out how much power I was running. The reason duty cycle remains relatively constant is due to the fact boost tails off as revs rise.

 

Last time I left it at that, but this time I'll go a bit further into it. The 94% is actually higher than the true duty cycle. This is because I have reduced the injection multiplier by 6.25% in order to be able to have a lean cruise condition (16:1) without O2 feedback. By doing this, fueling across the board is reduced, yet it will still be reporting the original duty cycle. In order to maintain the original AFR throughout the rest of the map, fueling was subsequently increased everywhere apart from low load areas. This results in a reported duty cycle HIGHER than the true physical duty cycle experienced by the injectors.

 

In short, duty cycle was probably 90%.

 

Hope that helps :)

 

P.S. When you get tired of no power and driving in fear of broken ringlands, you know where to find me :lol: :lol:

Edited January 5, 201312 yr by Noz

This is turning out to be quite possibly the most interesting factual thread I've read for quite a few years on this forum

I think somebody knows their stuff :D