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scott.mohekey
09-04-2009, 12:01 AM
Am I correct in saying that the thing dictating the use of high impedence injectors in our cars is the ecu, and that when replacing the ecu with a standalone unit we are able to switch to using low impedence injectors if the new ecu allows it?

Kenneth
09-04-2009, 12:07 AM
Correct.

Wodjno
09-04-2009, 12:11 AM
Standalone should cope with anything you throw at it /yes

scott.mohekey
09-04-2009, 12:12 AM
Am I also correct in thinking that low impedence injectors are more commonly available? I've gotten the impression that the high impedence ones are a pain to locate/are more expensive.

AlanDITD
09-04-2009, 12:17 AM
Have a read here mate.

Not sure what size your looking to go for but it gives a fair bit of infor RE injectors and which cars use which types.

Might help you with your search for a set

Cheers

http://www.robietherobot.com/Storm/fuelinjectorguide.htm

Wodjno
09-04-2009, 12:18 AM
Am I also correct in thinking that low impedence injectors are more commonly available? I've gotten the impression that the high impedence ones are a pain to locate/are more expensive.

Low impedance are more common and easier to come by /yes

AlanDITD
09-04-2009, 12:20 AM
High impedence are more common. Most OBD2 cars use high impedence as they are cheaper to produce.

Although low impedance peak and hold style are better.

scott.mohekey
09-04-2009, 12:29 AM
Yes, I read on the motec site that the low impedence peak and hold are better. That's essentially where I was heading.. if I want to use low impedence peak and hold and the standalone ecu supports it, I should be ok. There is nothing else in the setup dictating injector type? (aside from the shape).

Wodjno
09-04-2009, 12:33 AM
Low impedance are more common and easier to come by /yes

:zzz: :oops: :undecided :( :sick: /duh :embarasse :uhoh: :lipseal :toilet: :lipsrseal /dunce :skull: :huh: :huh2: :anxious: :end:

Glad tonight is the end of my Nightshifts /pan

AlanDITD
09-04-2009, 12:39 AM
Yes, I read on the motec site that the low impedence peak and hold are better. That's essentially where I was heading.. if I want to use low impedence peak and hold and the standalone ecu supports it, I should be ok. There is nothing else in the setup dictating injector type? (aside from the shape).l

No mate, the ECU is programable to tell it which tpe of injectors you have, Never seen motech in action though. Cracked ECU's from hondas for example using crome still require the factory resistor boxes as they are still using the factory loom iirc

scott.mohekey
09-04-2009, 12:51 AM
Cool, thanks all.

scientist
09-04-2009, 02:53 AM
You don't need a standalone ecu to run low imp injectors. Get a Resistor pack for a GTR or USDM supra


Scroll down to where he does the resister packs
http://bobthegreat.com/pages/mycar/mods/turbo/fuel.html


Then go out and buy yourself a set of Cheap FIC or Evo Denso 560cc injectors

scott.mohekey
09-04-2009, 02:57 AM
I'll be using a standalone ecu in any case.

Turbo_Steve
09-04-2009, 03:32 PM
Or, indeed, you can usually make a resistor pack with bits from Maplins :D

However as you're going for a Motec (you lucky...lucky...lucky *****) then you should be fine.
Will you be mapping it yourself?
Going to use closed-loop wideband for normal driving, and allow it to have AFR targets on open-loop?
EGT monitoring?
Boost control map? OMG OMG TOYS!
Sorry.....having a bit of a moment...

Eurospec
09-04-2009, 07:41 PM
M800 = the dogs!

Just having the target afr in there makes it so much easier to map.

Cheers,

Ben.

scott.mohekey
09-04-2009, 09:55 PM
I've been looking around at the various ECUs available and the motec ones seem to be the most complete package. They even have CANBUS!!

This is all for the project ute, so price is no issue. If it takes me ages to save for the various parts, so be it.

I've had a bit of a closer look at the motec offerings, and I think the M600 would be the best choice. I'm basing this on my understanding that the difference between the M800 and the M600 is the number of injector and ignition drivers. However, if the M600 is missing some vital features the I'll go for the M800 as its not that much more expensive (when compared to total cost).

As for EGT, boost maps etc.. I'd like to aim to use all the features available.

I'd love to be able to self tune, and will aim to do this. It will involve a great deal of research and learning on my part, but that's what I love about taking on a project like this.

Turbo_Steve
10-04-2009, 01:38 AM
If it's minimal extra outlay, I'd go for the M800...it's just got more toys (think Shiftlight output, ALG switch, TC, and, of course, if you fancy fitting an active centre diff later, it can be upgraded to control it!)

And if you're planning to map it yourself, the Motec (or maybe the Autronic) are probably the two best platforms to learn on. I'd reccomend you get yourself a set of Det Cans and a wideband asap, and start looking at what cars do, and listen to what the engine sounds like: get an idea what sort of noises it makes under normal conditions. Then stick a cruddy batch of fuel in and listen hard to how it reacts!

scott.mohekey
10-04-2009, 01:55 AM
Anything I can do to learn before I start outlaying large sums of cash, I'll gladly get into. It's probably going to be a few months before I actually get the motec sorted out. I have to build the engine up first.

scott.mohekey
10-04-2009, 02:02 AM
Something like this for the det cans? http://passionford.com/forum/archive/index.php/t-85339.html

Turbo_Steve
10-04-2009, 03:59 PM
That's exactly what I did!
There's a little bandpassing , which can make injector noise and sometimes parts of the valvetrain sound abnormally loud. Imprezas, for example, seem to have a definite "Jingle" to something in the heads, but I've never traced what it was.

In fairness, the copper pipe in the earphones isn't even neccesary: I used a length of garden hose and just drilled some tight "interference fit" holes in the ear defenders. The Tee Piece was something I found in Dads tool box, so I couldn't tell you where it came from. Then hammered flat one end of a bit of copper pipe and bolted that bit to the block. Jubilee clip the hose on, and job jobbed.

Be aware that there is no way possible to wear this getup and not look like a spanner. I've used more expensive, electronic systems, but TBH they are only as good as the headphones you use......and by the time you've spent £70 on some decent ones, you find that they're not that much better than the cheapo ear defender hose pipe method!

scott.mohekey
10-04-2009, 09:51 PM
Excellent!

I'm not overly fussed about looking like a spanner. The car will probably be half finished when I start tuning anyway. So I'll look a bit daft anyway.

Turbo_Steve
11-04-2009, 01:01 PM
That's pretty much the way of it.....LOL...you never end up looking like you're something out of fast & furious, with some amazing looking car with 300,000 bhp....it's inevitable that you end up with a 600bhp car with bits missing and 3 colours of paint and filler and plastic bits, that has some electrical gremlin that renders you incapable of overtaking the blinged up saxo / nova / ford shopping vehicle that blows you away on a straight road whilst you're wearing your "ultimate pulling" det cans and fiddling with the laptop whilst the driver sits there with his foot flat making about 55bhp.

It's all part of the fun of building a monster.

Eurospec
11-04-2009, 03:29 PM
/pan LOL! Oh sooo true!

I did an mr2 turbo this week. Went really well! Took it out for a spin- split a fuel injector seal and dropped all the fuel pressure! At the side of the road getting tooted by grannys!

Cheers,

Ben.

Turbo_Steve
11-04-2009, 03:47 PM
LMFAO! IIRC they're top feeds, so at least it didn't fill one of the bores with fuel and hydrolock the engine. Inevitably a call to the AA, or some roadside bodging required.