Stevieturbo

So are you measuring power/torque on a dyno to come to these timing figures, or guessing ? And detonation is easy....listen. Your Plex offers you headphone sockets for this purpose, as well as the electronic/visual aspect. If this isnt ok, then plain and simple old manual det cans are extremely effective. Run it on the dyno and listen.

Sounds like you need to be using better tyres or diffs. I've worked on 600hp+ 4wd cars for hills etc, and ok yes the wet can sometimes pose challenges...but rarely the dry. And other than at launch, which would have it's own specific requirements anyway outside of traction control, very rarely are there full 4 wheel losses of traction. Anyone crazy enough to fully exploit that sort of power on a 4wd car on proper tyres....the last thing most would want is TCS intervention. Although the ROC of a driveshaft under these circumstances would be different than a more rapid ROC for loss of traction via 1 or 2 wheels. But again all of that is still down to fine tuning the system, which would be the case regardless. Taking the ROC back a step further.....ROC of rpm is another means of determining what is normal acceleration vs a loss of traction. But again there are variables and it could get quite complicated. But when you look at logs of any run where there is grip, vs traction loss....it's always apparent in the rpm trace. Making use of it would be difficult though, but probably not impossible. Even a 4 wheel system would still have some functionality for TCS, except the circumstances where all 4 wheels slipped at the same rate, which lets be honest would be rare. So that conventional setup culd probably still be utilised to a degree in the absence of any other means. Even with a GPS based "undriven" speed reference, you'd still need to spend a lot of time tuning the system for each track/surface/driving style. GPS can and does work for a speed reference, although for hillclimbs, especially if there is tree coverage etc this can affect the signal quality, although any GPS I've used tend to read lower under these circumstances, so TCS simply wouldnt activate so it shouldnt really impact too much on driving. I'm sure a good external aerial would help matters here though and the modern 50Hz stuff is probably a lot better than the 10Hz ones I've used. No matter what route...it will all be a lot of trial and error. But the easiest is power management from the outset for the track and conditions, with perhaps a power setting or two the driver can adjust if need be. Getting a TC system wrong though, can be utterly rubbish for a driver though and can affect the controlability of a car, especially if it is one the driver might throw or slide about. But log the 4 wheelspeeds first and see how they actually are.

Under what circumstances is this wheelspin ? Straight line, corners, launch, other ? The simplest means of preventing wheelspin...is power management to prevent it in the first place. Is one wheel a problem, one axle ? all wheels ? A decent GPS unit shouldn't have any lag that would cause major problems and if for whatever reason traction is so terrible, it'd still be better than nothing at all. but as others mentioned, some companies offer TC based on rate of change of a prop/driveshaft which can be viable if the software allows it. Not sure it'd be suitable for all applications, and as with any TCS, would require development time

There are any number of trigger wheels available in terms of size, diameter, tooth setup, it shouldnt be too difficult to fab something up for a solid reliable trigger. On my old RV8 and now LS, I just machined the rear side of the crank pulley a little then welded a 36-1 wheel onto them and added a VR sensor ( done before the LS 24x was accommodated on most systems, although the 24x wheel they use is shite and I wouldnt use it now anwyay ) Trigger setups can be done very cheaply if you want. My wheel and sensor would easily be less than £100 total.

Because as he said, the factory ecu was designed to work with that trigger, so it is capable of doing a better job than aftermarket units. Maybe Nissan ignore the multitooth aspect once running or something, and pay more attention to the phase side of the trigger etc which with less teeth would be less prone to inaccuracy problems.

What's a duel table ? For dwell, it's entirely up to you, nominally they will say 2.5ms is enough time to give the quote spark energy they claim. Some will charge them for longer than this though. Whether you need more charge time is entirely up to you and your setup. It's been a while since I tested, but from memory I think they saturate around 5-6ms. Depending on engine rpm though, you may or may not have that sort of charge time available anyway.

Some of the logs you posted, record the ecu live, engine not turning and MAP changing at varying levels, both vac and pressure. key on, engine off should be around 100kpa ( and this appears correct ), ie atmospheric. So are you saying you were not messing with the map sensor when these varying readings were happening ? If so...why where they happening ? it looks like they are being tested. Mityvac should easily be able to get to the 60psi or so their gauge goes to, although a test to 20psi gauge pressure should be fine.

The Nissan trigger system is a bit of a mystery. For them to go to the trouble of creating a trigger with so many teeth...optical for supposedly better resolution or something...and then to stick it on a camshaft on the end of a belt !!! The designers must have been eating Vodka laced sushi that day Really it should be one of the first things to throw into the bin and move to a crank trigger when tuning any of them.

What sort of resolution does the Pico sensor offer ? A lot of pressure sensors I see claim 1ms, ie 1000Hz...so realistically...will the Pico be any better than that ? The Autoscope one sells for around 105 Euro or so although they're bloody awkward to buy from taking Western Union. If it wasnt for that, I'd have bought a kit already. http://autoscope.eu/products/ They list it too as a -14.7 to 500psi sensor, so probably not ideal for petrol engines. I bought a cheap compression tester and added this sensor to it, and it seems ok at cranking and idle. Doubt it'd work that well at high rpm though. https://uk.rs-online.com/web/p/pressure-sensors/1115919/?relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D626572266C753D656E266D6D3D6D61746368616C6C26706D3D5E2828282872737C5253295B205D3F293F285C647B337D5B5C2D5C735D3F5C647B332C347D5B705061415D3F29297C283235285C647B387D7C5C647B317D5C2D5C647B377D2929292426706F3D3126736E3D592673723D2673743D52535F53544F434B5F4E554D4245522677633D4E4F4E45267573743D3131312D35393139267374613D3131313539313926&searchHistory={"enabled"%3Atrue} Really...it would be nice if the aftermarket ecu makers, could start to integrate some of these diagnostic modes into their ecu's, seeing as they already receive a lot of good information. Relative compression tests would be a doddle, crank/cam ( and other sensor ) scope traces etc

Whether 34psi or 54psi base pressure...little odds. Although typically base pressure would be around 45psi with no vac connected. I personally would not go lower than that, but each to their own. If crank trigger has not been touched, then no there should not be a need to confirm timing etc....but as you are having very strange readings/problems, a simple quick test makes sense. I presume your first log is with you playing with the Mityvac ? If so, why in the middle are there two incidents where throttle appears to have opened ? Did you do that, as they seem very brief ? and in your last log there, why is the map sensor stuck in the 140kpa range ? Unless you have some wiring issues....or plumbing to the map sensor issues...replace the map sensor.

Just use a 3 port to do the same thing, but create a very small vent hole on the top chamber ( ie that blows the gate closed ). Circa 0.6mm or so, MIG tip is handy. You lose a little top end pressure, but it makes control much easier overall. In most cases there is no need for separate control over 2 solenoids. Keep it simple.

So you're saying key on, engine off, the map sensor correctly reads atmospheric pressure, as it always did ? And when you test with a Mity vac, it behaves as you'd expect both into vacuum and then positive pressure reading via PCLink ? Not sure how anyone could actually install cams so badly, nevermind have the engine run with an actual 6psi positive gauge pressure in the intake at idle. Can you compare a trigger scope of crank/cam trigger before/after to see if there are huge differences there ? Can you confirm ignition timing is as expected ? IDC seems very low, even for idle, what are mixtures like ? Compression test ? And why on initial cranking on log 1 does MAP reading hit the floor ? That is not normal, and could be more likely a wiring or faulty sensor or something. Because the engine should never be able to achieve that, nevermind that it then shoots to over 100kpa as rpm rises a little, again not possible.

On the topic of running compression tests...and sensors etc. Any thoughts on this gear? It's a lot cheaper than Pico, the gear/software is Ukranian based. Their pressure transducer is a fraction of the price of Pico's, although no idea what resolution either offer. The software shown here looks pretty cool ( I've never used a Pico though so maybe it can do similar ? ) I've used a cheapish Honeywell sensor for a few tests logging on my own car, it claims less than 2ms response, so around 500Hz i guess and logging at 1000Hz it seems pretty decent. Could only find a 500psi absolute sensor though, which wasnt ideal.

Why would you want to, what do you think, or are you trying to achieve ?

Such an actual engine protection feature does not exist, but you can create a low rpm limit based around load/lambda and base any cuts around this which will work ok.

You will never see 300psi, nor will 2x1000cc nozzles be as efficient as smaller nozzles. Well other than when the pump is pumping against the closed valve and if the pump has been adjusted to see a higher pressure. In fact, with nozzles that large I'd be surprised if you ever see much over 100psi. The pumps simply do not flow what the suppliers claim, and any pressure claims are against a dead head. I've tested the AEM big pump under load and in the real world at pressures required....realistically they're only around a 1200-1300cc pump, and that was with a quoted 1600cc worth of nozzle...and tested not fighting against boost pressure which would reduce flow further. Even with only a 600cc nozzle...my factory set 200psi pump, could never create 200psi. With 1600cc worth of nozzle, in the car, in real world use max pressure I see is around 140psi....so if using say 40psi boost, that's now only 100psi of effective pressure to inject, so even less flow. But stick a pressure sensor on the line and log it for yourself and use this to control any fuel/spark adjustments, rather than what you're currently doing which offers no failsafe. It's a cheap and easy way to monitor what the system is doing, and could be an eye opener. It's a pity nobody seems to have done much testing on the various systems and pumps out there to prove or disprove the suppliers claims.

Typically they are a 2 wire switch, and yes there would need to be a pullup from 5v to the signal wire if the ecu cannot provide this internally. IF the switch has been done correctly than that should give rising voltages from lower positions to higher positions. Pretty sure it will be polarity sensitive too. Or if building your own switch, you could probably do this with a 5v/signal 2 wire setup, cant see much need for a ground wire. Post a picture of the switch.

A base map is there to start the engine to allow it to be tuned. Which it seems did apply here ? Trying to copy other peoples maps in the hope they might do something for you, is dangerous. Have the engine tuned properly by a competent person otherwise you risk damage.

Devilsown will probably want you to use their controller, and kit in general obviously...and there's nothing wrong with that. Really, discuss it with your tuner, to see what he can make work for you and your needs. If you can add a flow or pressure sensor on the line and apply any fuel/timing corrections based on that, then that can be the basis of a solid failsafe with regards tuning should the system fail. Although done right, they are very reliable these days. But with control on-board the ecu and via a SSR for the pump or similar, it just gives the tuner a bit more flexibility with how "progressive" the delivery can be. If just PWM'ing the pump, as most aftermarket controllers do anyway, then it doesnt really need anything fancy, simple works. So it's largely down to your tuner to decide how much water/meth they want to use, when they want to inject and how aggressive they might want any tuning to be

Depends who's putting it all together and tuning it. Using the ecu could save some money as it removes the need for an external controller, but there really are a few ways you could do it, each with various pros and cons. Standalone setups are perhaps easier for a novice, but either way it will need tuned anyway so someone competent needs involved to get it all working properly.

There is no possible way you are making 0.9bar positive pressure just sitting still and revving the engine unless the tuning/build is diabolically bad, or you're running massive anti-lag or something. Both will be harmful. Normal running engines DO NOT make boost with no load on the engine.

If you're letting off the throttle during a shift....it isnt a WOT shift ?

Well hopefully you can now move forward. Depending on damage, there is no doubt it could be repaired for substantially less than 6k....although I guess that depends on what currency lol.

I'd load the scope to view.....but surely the software would allow one to do this offline ?

Some 2 wire sensors on ABS are a strange hall effect that need powered Are you sure your 2 wire is a regular inductive sensor ? Have you grounded the wire to signal ground ? Not battery or chassis ground. Can you scope it to see if there is any reaction at all from the sensor ?