TTnet link

 

I'm somewhat amazed/intrigued by this Z on TTnet. It's an old link so I didn't think it was worth asking any new questions on there, and I thought I might get a better (more detailed) response here.

 

The bit where he says "Rather than 555cc injectors he just used two supplementary TT injectors and he is running around 90 psi fuel pressure under boost." has me wondering.

 

So would that be a fixed 90psi, injected the same way that the extra fuel is for nitrous? (to the inlet manifold or cylinder head).

 

I presume it would be linked to an electronic boost gauge or some sort of boost pressure switch to trigger the extra injectors when positive boost is shown?

 

How would you stop it running rich under low boost? The only thing I could think is by setting the air/fuel map so that the standard injectors drop to a lower flow/pulse than normal at low positive boost when the supplementary injectors are kicking out full 90PSI (more than needed).

 

What are the pros and cons of this system? Presumably lower cost than higher flow injectors, as long as you already have an air/fuel controller? Would the fact that the fuel is being mixed in at the inlet manifold like nitrous mean a less even distribution of fuel than separate injectors?

most put an extra injector in each rubber intake hose and it needs to be controled properly by something like a HKS additional injector controller. Not the best way as your plenum is designed to run dry and you can never achive exact fueling to each cylinder as the fuel has a lot further to travel to the back cylinders than the front ones. The controllers are not cheap so it would be just as economical to buy bigger injectors in the first place and you wont need the complex setting up of the aditional injectors too.

Paul

Hi

 

Mine runs 2 extra injectors, its only really done by SE or it used to be done by them i dont think they do the upgrade anymore.

 

It runs very well (well if i hadnt broken it) but it is very thirsty so i'm taking it off and putting larger injectors and a new ecu on it.

 

Speak to peter at SE he will tell you more about it

 

Cheers

kirbz

Whatever you do, do NOT talk to me about supplimentary injector controller modules, or look in my ride section ;)

LOL Mike I've just had a thought - lets see if its the rear most cylinders that are screwed. My bet is its the front two, getting bore washed because they are recieving more than their fair share of extra fuel :eek:

 

Additional injectors don't really work on a 300 as the plenum design is shite. It has a hard enough time distributing the air evenly, never mind shifting an air fuel mix. Additional injectors are actually a great idea. Injecting fuel further away from the cylinder actually promotes better atomisation and cooling of the charge. The only reason the injectors have to be so close to the intake valves on an engine is because the air velocities at low rpm are so low that the fuel would have fallen out of the air before it got to the cylinder - ie the engine won't run. Some competition engines have 2 sets of injectors switched. It uses the closer set at idle/low rpm then at certain rpm gradually changes over to the further ones. For most power, you want a good distance between the injector and the cylinder. For smooth idle and drivability, you want nice short runs from the injector to the cylinder. Its all about air velocity.

 

For additional injectors to work well on a 300, you would either need to redesign the upper intake plenum, OR fit an injector into EACH LEG of the upper intake. The latter option would be absolutely awesome but I'm not sure if there is enough room.... The biggest bonus of additional injectors is that they also cool the charge, giving a denser mix, giving more power... GRRRRRRREAT :D

 

HTH

 

CheerZ,

 

Andy

I was speaking to Peter about this a few weeks back.

He said that the additional injectors where used a long time back, before the craze of using 555's came into play, so there doesn’t seem much point in having these now, you may as well just fit bigger injectors.

Cheers Andyd

 

Speak to you later tonight

 

Mike

Well now that I know that there are off-the-shelf supplimentary injector controllers available that makes things easier to understand. The idea I was toying with was a semi-budget upgrade (not including cost of new intercooler, ecu, turbos, suspension, intake, fuel system, etc, etc...). I thought that there may be some extra benefit to running the supplimentary injectors, or a big saving by using supplimentary stock injectors from a scrapper.

 

51x - Does that supplimentary injector controller that I'm not supposed to talk to you about actually work :) or was it an abandoned project? And whats with the picture of the french toilet - a final resting place for the supplimentary controller?

Originally posted by gibbon666

....And whats with the picture of the french toilet - a final resting place for the supplimentary controller?

 

Maybe its NOT a supplimentary controller - maybe its a SUPPOSITRY controller :D

Originally posted by gibbon666

51x - Does that supplimentary injector controller that I'm not supposed to talk to you about actually work :)

Don't talk to me about it! :D Yeah, it worked to a point... ie. the bit I done (the controller) would work on a 300. We tried it on a 200 just cos it was quicker to plumb in one injector but the RPM timing was out (4 cyl you see), so I had to do a bit of fiddling to try to work out where the RPM thresholds would be. It was kinda interesting trying to keep an eye on the LCD while Pete® charged up and down various windy country roads.

The module was hooked up in my car for something like 2 years without the extra injectors! If it'd ever been sold it would've needed to be more compatible with any car, rather than being 300 specific. There was guy lined up to write the PC stuff too, but noone really had the time to put the effort in that was needed.

I couldn't be bothered with buttons and stuff when I knocked it up, and there's no PC link... you had to set it up by hand with a $ky remote :) Lovely bit of code tho (if you like that sort of thing).

 

I can't go into detail about that French toilet here.

Greddy do an injector controller:

 

http://www.overboost.com/obs/product.asp?pid=402

 

but for another $100 you can buy a set of 555's!

.......plus cost of extra injectors, plus cost of hard pipes, plus cost of having injector bosses welded to hard pipes, plus fuel line......

 

Set of injectors requires a set of seals and an upper>lower intake gasket. Labour time wouldn't be too different between the two considering the aic/whatever will require setting up once fitted...

I think the Greddy E-Manage can handle extra injectors too and that's not a bad price if you wan't to upgrade all sorts of features in one go.

Just checked Greddys site and you're right, the E-Manage can control 2 extra injectors. Hmmm... E-Manage + E-01 is tempting.

 

I also checked the Dastek Unichip site as well (as it is just another piggyback fuel management setup) and apparently that can control extra injectors as well, although it doesn't state how many.

 

As I was planning on some sort of electronic management anyway, this gives me 2 options to look at now.

 

Although I haven't decided how much power I want to acheive yet, I was thinking of going for something around 660cc injectors and then a couple of supplementary injectors for when high level of boosts kick in. The Greddy might be better, as then I could set different maps for low boost setup/road driving (whereas the Dastek has to be done by a dealer I think).

 

51x - Have you done an IC fogger/mister/spray thingy while you've been playing around with electronics? Or could you copy one if I bought an aussie one that looked quite good?

Originally posted by gibbon666

Dastek Unichip

Erm... I'd avoid these.

 

660cc injectors and then a couple of supplementary injectors

Blinkin' flip! 550cc's are apparently good enough for 600-odd bhp! How much boost are you thinking of running?!

 

an IC fogger/mister/spray thingy

No I haven't, but not because the electronics are hard. It's more the extra plumbing you'd need - OK you could use the headlamp washer motor but you need a fresh-water bottle somewhere. And some decent squirters to make a nice fine mist. I doubt you'd really need a full-on PWK generating controller to squirt variable amounts of mist either - it'd probably just be a matter of turning on the mist full on at some point. I've no idea how much benefit it would be either.

 

Or could you copy one if I bought an aussie one that looked quite good?

Nice idea. TBH I don't make car performance stuff for a living but I got involved with the injector thing because SE wanted to do one and I've known them for years. The idea was to supply a complete kit, with config software, injectors, pipes, etc for less than the price of a set of 550's and a remapped ECU. It would be there so there wasn't such a large step from what you could do with standard injectors / standard fuel pressure. SE do a fuel pressure upgrade thing, with ECU remap too (get's more fuel through standard injectors). I'm pretty sure they've had 420-odd bhp from a car with that setup.

The IC mist thing - I'm sure if Pete (SE) wants to do one we'll no doubt end up talking about it at some point. We talked about doing traction control - not all that complicated really - but I've gone and bought a Racelogic one now anyway ;)

The washer motor, water source, nozzles and plumbing wouldn't be a problem. I've got some ideas where to get them. I just could do with 2 or maybe 3 of these controllers, as I've got uses for the other ones. I'm a cheap ******* though and don't want to pay out full price for 3 :).

 

As it's for a one-off install, I'm not looking for a pretty boxed kit or anything, just copies of the board, unless there's a better way to do it. No doubt all 3 separate triggers and controls that I want could be wired in to one box, but that involves original design etc and would no doubt bump up price/time/testing.

 

I've put the links below for the aussie board. The concept behind when the spray triggers seems logical and quite clever.

 

Review of the aussie water spray

 

The manufacturers site