barf
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Posts posted by barf
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try using the tooth logger in TunerStudio -- it's pretty much a poor man's scope, albeit located after the ADC/VR conditioning circuit
edit; i think using the 4-pronger is going to leave something to be desired in terms of resolution in the signal, which could lead to timing errors. the 24 tooth (Ne) signal was added to the newer dizzy's which as someone pointed out, might be a good solution offering you direct ignition also.
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my e30/m20b20 has a similar curve, AFAIK it's an acoustic/pneumatic type of issue with intake manifold. i thought Toyota solved this with TVIS though? seeing the torque fall with it raises an eyebrow though, i assume that would be timing - what's your spark map/advance table look like?
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is it MS1(eek) MS2 or MS3?
are you triggering on leading or falling edge?
i doubt dwell is the issue, simple things first; how free from noise are the VR signal(s) at the megasquirt-end of the loom?
for the VR signal, i'd use twisted-pair at the least or preferably a fully shielded cable.
you might need a 'scope, setting my VR zero-crossing (R56) and hysteresis (R52) on my jimstim helped but on the vehicle it could be different. i made a crappy youtube video a while ago, which might help -
also, be sure you understand this document
http://www.megamanual.com/ms2/vradjust.htm
EDIT: could you drop your msq and a datalog here also?
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I agree, these are pretty good cars for the price I reckon and I will leave stock as I already have a toy
Apparently most if not all NZ new ones had LSD like this one as standard fitment.
never tried drag racing, would you be keen to give me e30 a go at ruapuna on the 13th? (assuming it's the pbdrc event?)
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hello and welcome!
sorry not too familiar with your engine's ignition system but i've used Bosch BIP373 IGBTs ($8 TO-220 package) to replace BMW and Toyota ignition modules. these require a logic signal with dwell to discharge the coil and so would suit fuel injected cars that provide dwell control from ECU - many ignition modules do dwell control themselves so they're not quite a drop-in replacement unfortunately.
any idea if the module connects to the computer or the dizzy?
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ouch, i've seen solid prop shaft bushings for sale on a dutch website
the E30/M20B20/5-speed i have got treated with a $500-max budget which yielded some modest improvements
installed a megasquirt 2, wasted spark coil-pack from a V6 commodore, throttle position sensor (these M20/M30's have WOT switches) and borrowed a wideband O2 sensor to get VE tables tuned, just did the spark map on a spreadsheet and calculated values for 95 RON. i also get the impression the standard manifolds are hard to better, altho i've seen (GT-R?) slide-throttle ITB's on one M20...
the two hours at the dyno shop (which included 40mins for setup and teardown) didn't actually gain me much power!
(i've since improved the off-idle torque and the flat-spot at ~3700)
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I've never encountered an even minute amount of discrimination from Police in regards to old cars. Ever. I find the thought decidedly more preposterous for well maintained old cars.
where do you live? i want to see this utopia one day
also, another important fact:
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TLDR k-trips, get a clue.
i took legitimate concerns from the community to the IPCA, then select committee and objected to the new 'boy racer' laws.
the cops called back and a 16 and 17 yr old both got locked up.
good work NZ Police.
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So normally they wait several hours/days/weeks before pulling you over and popping over to your place and giving you a ticket.. lucky devil....
i have been threatened with violence by some P fiend in a road rage incident and the cops refused to fucking do anything and let the guy go. fuck you if you think sarcasm is funny. you think i joke about discrimination?
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i must say, the police response was good (2 minutes), which is in stark contrast to my experiences of discrimination for driving old, well-maintained cars...
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two idiots are about to be apprehended for thinking that seeing a mint TA63 and S12 was an invitation to take my stuff.
they made a lame getaway in a red/maroon Diesel Nissan Terrano 1996
plate no. BEC355
6ft tall light build caucasian male
wearing a light-grey beanie with stripes which had ear flaps with tails.
the cop knew exactly who they were when i described them. thief fail.
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I thought the faster opening times were a product of peak and hold control method.
from what i can gather, low-Z injectors are typically higher-performance and have higher flow rates, shorter opening times through better construction and it's the low resistance of the solenoid windings which mandates the requirement of PWM and current limiting circuitry, primarily to avoid overheating, which leads to insulation failure. you can peak and hold high-Z's but that doesn't improve their operation over simple switched open-circuit driving.
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Fitting a resistor pack will increase the impedence.
and do away with the benefits of having low-impedance injectors, such as the faster opening times.
resistance and impedance are subtly different things
you can exchange high-Z with high-Z injectors but putting low-Z injectors into a high-Z system is opening a can of worms. you'll need to create an 'equivalent circuit' using the low-Z's with the same electrical characteristics as the high-Z's the ECU is designed to drive. while that's not impossible, you can use a resistor pack, it's more complicated than just using the correct high impedance injectors which can safely be driven in open-circuit style. low-Z injectors need current limiting circuitry which is why a resistor pack would be needed. honda actually tried this for a while and had problems with transistor junction temperature in their ECUs causing premature failure.
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simple things first. had a head unit installed recently?
dropping to 10v or 11v while cranking is normal.
i'm in chch too, PM me and i could take a look for you.
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don't use low impedance injectors unless you have an ECU designed for them! putting a resistor pack on low-Z injectors does away with the benefits they offer anyway. high impedance injectors have different control systems (simple FET switch) while low-Z injectors require PWM control with peak-and-hold to operate correctly.
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if you send it away, they'll need to know how much to adjust it by
using your data, the correction factor would be 1.24 (aka +24%)
50 62 1.24 70 88 1.25 80 99 1.23 100 124 1.24
DIY electronic speedo could be easier/cheaper?
Jaycar sell kitsets for like $50 which can adjust signal frequency.
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i'd start with MS2 at a minimum, MS1 is pretty old now. he won't need to lose a prong, unless, the OP wants wasted spark and/or sequential injection?
the 18R-GEU dizzy can be used for fuel injection in bank-fire without modification, if spark distribution is done through the dizzy. the stock ignitor contains a VR signal conditioner and outputs a digital signal suitable for (simple) timing control in an ECU. only problem with this, is you have no reference for TDC to cylinder so wasted spark and sequential injection wouldn't be possible.
edit: helps when i read the shit i'm replying to, the 18R-GEU dizzy is not gonna help you go wasted spark or COP, sorry EURON8. but, the 4agze pickup does have the goods inside it you need.
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ah what a dilemma, not trying to knock EDIS either, i'm sure it's a good system
my 18R-GEU had a VR sensor in it's dizzy, it was basic (4 pronged, 'electronic points') but should work fine.
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What ECU are you going to run? If I was going to modify something to fit I probably wouldn't bother with any of the toyota VR stuff especially with a Megasquirt much easier to go optical
why bother with EDIS? Bosch BIP373s are newer, cheaper and give a hotter spark. i found the Toyota VR cheap and easy to use with Megasquirt anyway.
Connecting a Megasquirt to one of these pickups requires two LM1815 which are like $8 each, and if that's too expensive; a small circuit with a couple of $3 op-amps will do the trick too. alternatively, there's the Zeal engineering daughterboard as a DIY kitset which costs USD$35.
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nice engine bay mjrstar! (CT9A? mine's a CM5A)
no trouble codes logged in OBD, knock sensor isn't picking anything up and the timing and boost is standard anyway. (yes 1 bar standard)
what plugs do you run in that and where did you source those COP units from?
do they have a built-in ignitor? (2, 3 or 4 wire type?)
i was looking at ordering one of these coil-packs along with some more Bosch BIP373 IGBTs but shipping out of the USA is not cheap :-/
you got the idea but, option 4 is option 1. having more than the breakdown voltage is what matters and upping your coil's primary side from 12v to 24v will do that but then the insulation of the coil degrades much faster and you'd need to re-tune the dwell time to avoid frying it. a higher turn ratio (more windings, and more evenly wound) is what provides more voltage at the spark plug's electrode tip. COP seems to be mostly a reliability/cost design decision, as high voltage leads are not cheap and prone to insulation failure, while the voltage and current losses through HV leads are not huge (better RF suppression is also achieved with COP).
interestingly, you can have enough spark to initiate deflagration and have an engine run very smoothly, but extracting the most power (esp' at high pressures; ie turbos) puts higher demands on ignition systems than what is required to simply make them 'run'.
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just read a few journal articles online about spark gaps and discharge, the UC library is awesome
the breakdown voltage of the gap increases with pressure, and gap size. the gap has near-infinite resistance until this voltage is reached, and reached with sufficient current (minimum dwell time).
you get a spark when you discharge an induction coil which has more potential energy than that breakdown voltage
in atmosphere (1 bar) at 20C that voltage is approx 10,000 Volts / millimeter
from what i can gather, there are three methods to yield the best flame kernel expansion in cylinder, assuming an optimum air fuel mixture and ignition event timing.
* increasing voltage beyond breakdown voltage
* decreasing electrode sizes
* increasing spark gap
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do not forget occums razor
the bosch water temperature sensor is a negative temperature coefficient type
the sensor can be checked with an ohm-meter and thermometer over a pot of water on the stove.
Celsius Ohms -18 12000 18 2315 94 250
you could check the gauge using the same resistance values in place of the sensor. old BMW electrics are lots of fun.
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thanks again for the replies everyone! what is obvious to some totally slipped past me!
gapping down to 0.6mm did hide the misfire, but it's still missing power and i suspect still burning rich at high loads.
i know the rule of thumb is to reduce spark gap as cylinder pressures go up but, that idea has one very important flaw: if the energy in your spark remains constant but cylinder pressures are increased, reducing the gap only serves to create a smaller area of ignition with the same amount of heat. this provides for slightly less ignition of the fuel/air mixture, compared with same gap and more voltage, or am I mistaken?
Ignition only systems for injected engines running carbs
in Tech Talk
Posted
the megasquirt does ignition, fuel or any combination of. perhaps not the simplest but, it's hard to find better deflagration control systems.