Okay, a couple questions for the tuning gurus out there, (no poseurs please u know who u r;)
I am running a TC and want that to provide enough fuel for 450 horsepower at the 85% injector ontime SOOOOO what injector size provides this amount of fuel at its 85% ontime???
Also what fuel pressure would it need to be at?? I dont want really high rail pressures. Obviously It will be higher (already is) but I dont want to reach reaaaallly high pressure...
Thanks in Advance for any info that you provide...

For 450 hp at the motor, you will need four roughly 620 cc injectors. That's the easy part. The hard part is finding one to fit the Subaru...as far as I know, there are none at this time. Subaru uses a saturation type injector, as well as having them be a very high impedance. As such, there are not alot of offerings. You can do it the cheesy way, and fit resistors (or it might be ballsts...I am not quite sure, as we have never done it) to each injector, allowing them to show a higher impedance to the ecu...the problem is you will never get the injector to truly behace as it should. Don't get me wrong, this can be madeto work (Bell does it on their Miata Turbo kits)....it's just not an ideal situation that's all. If you guys want to do this, let me know, as we are an RC Engineering dealer (only problme thereis they primarily push Lucas injectors,which are the K-Mart of fuel injection, as they tend to be unreliable. When doing fuerl system mods, you are always better off going with an injector that was an OEM offering for a car if possible...this ensures much better reliability. We personally preferto use either Denso or Bosch, as we have yet to have a problme on any customer car using these injectors.

As far as I know, the biggest high impedance injector available at this time in saturation type is a 550 cc...good enough for around 400 hp at the crank. The only issue here is that the connectors are different, so an adapter loom would have to be made to hook up to the Subaru injector harness.

I do have full access to all the STi injectors, including the 22B ones...if anyone knows the flow ratings of each, let me know and I can do a group buy on them.

Are you sure HKS, Blitz and Greddy do not have something? That seems unusual to me. I never use RC units. They are rebuilds.

I don't think the impedence matters when you are using a Wolf or a TEC 2.

Originally posted by adam99rs
Subaru uses a saturation type injector, as well as having them be a very high impedance.

FWIW, saturated, by definition, means high impedance. Just as peak-and-hold implies low impedence. If anyone is considering 600+cc/min primary injectors, they should seriously consider running low impedence injectors (without ballasts) as they will allow for much smaller on-times. On times that you will want to operate at if you expect your car to idle well and cruise reasonably well. This means that you will have to use injector drivers other than stock, which will require new engine management. Of course, at 450+hp, that goes without saying, I guess ;) Another alternative for big hp applications is to runs staged secondaries. That is, one additional injector mounted carefully in each of the intake runners-- eight in all (including primaries). Using this method, you could keep stock 420cc/min as primaries and mount four additional injectors (anywhere for 250cc/min on up). Most programmable engine management systems are capable of running staged injector set ups. And they really start to make sense when you're running a small displacement engine at very high boosts 20+psi. Done right, you can get the best of both worlds, high power output will stock-like low load driveability.

Cheers,
shiv

Blitz, HKS, Greddy are nothing but OEM injectors (usually Denso) that are equipped on other cars. I agree with Shiv completey...I think the best overall way to do it is to run additional injectors. We've done a few NA-turbo conversions on a variety of carsusing a simple MAP dependant configuration (where the additional injectors use their own MAP sensor). Under boost, the secondaries kick in, providing the extra fuel needed, but the primary injectors are the OEM units.

Shiv - does the TEC allow you to configure the system for either low o high impedance, r is it designed with one type in mind? Reason I ask is because I need new injectors for my Datsun (currently running 6 480 cc units...not nearly enoug for the 600 hp we will now be making), but again, I don't want to go with RC units. There is a BMW Motorsport injector made by Bosch that is 720 cc...six of these would be just about the perfect size for 600 hp. They are the "old school" hose type, which is good (allows me to keep the original fuel rale design, although we will bebuilding a higher volume one). I forget the impedance of the injectors I currently use, but I know these Bosch's are the opposite....so, will can I re-set up the TEC2 to run these new ones? Thanks

Adam,

Yes, the TEC-II can drive both types of injectors with no modification to the unit itself. With the low imp. injectors, it simply delivers more current. Just like an audio amp driving to drive low impedence speakers. As imp. goes down, current draw goes up. In the case of the stock injector drivers (which are used with the Link ECU), a lower imp injector will demand too much current-- potentially burning out the drivers.

As for driving secondary injectors, all that is required is a little in-house modification to the TEC-II's General Purpose Output.

Cheers,
shiv

PS. I've never had a problem with Lucas injectors. In fact, I've had more problems with Bosch and JECS injectors. YMMV, of course.

Shiv you have mail :D

so is that the concensus then?, I will need approx. 620 cc (assuming I can get 450hp at 85% duty cycle?) injectors or staged secondaries, i really dont know about adding those fuel lines and tapping into my manifold though...maybe if i had seen it done on an ej25 before, but I hate being a guinea pig...
and I am running an aftermarket ecu so high/low imp. is not a problem...

Is there anyone else who thinks a different size inj. is needed?
thanks again all...

bump:D

660cc injectors on the way from Venom! WOO HOO!

Tell me more please.

-Nathan

when they arrive, let us know whose injectors they really are (Denso, Bosch, etc.) as Venon (like RC) only rebadges them.

so does anyone think the 660s should suffice?
taking into consideration not hitting 100% duty cycle?

Actually, Python Injection makes the injectors.

no they don't...trust me on this..that is like saying HKS makes their own upgraded fuel pumps and fuel injectors, or Subaru makes their own clutches...they re simply rebadging an OEM injector that is already offered for another car...might not be an injector that is even possible to get in the US< but injectors are like tires...there are literally a handful of manufactureres in the world, and Python is not one of them.....there is Bosch, Lucas, Nippondenso and just a couple others. Python is the parent company of Venom.....Venom is simply the marketing name.

No big deal really, as long as they have one to fit your application. What did they charge you per injector if I may ask? Like I said, when they arrive, post details on them (any part numbers, wiring on the injector, color of the connector, etc......this will help us all trace whose injector is it....

ok I really am not worried about who makes the injectors at this point, I just want to know what size:confused:
Oh and I was pretty sure Python made the injectors...but lets not get rowdy; like you said you don't know who made it as well...

660's will be plenty for 450 at the crank at 85% duty cycle. Next thing to find out would be what the range of the stockfpr is...is a 1:1 unit obviously, but you need to know how high it can go up to...

also, which fuel pump are you running?

no rowdiness here at all.....just don't want people being confused by marketing names vs. actual manufacturers

My fuel rail is already highly modified, and a pump capable of holding that much horsepower is already in the car, so all i needed was the injectors, thanks Adam.

How about these ? 850 cc high impedance injectors from Power Enterprise, bolt-on items for WRX and STi 99/00 rails. We have a JUN prepared '98 2.2L Stroked wagon running these at 2 kg/cm² boost and a '99 Japan spec WRX wagon running the PE1820 Power Turbine at 1.5 kg/cm². The JUN wagon now runs a Haltech ECU while the '99 wagon is powered by a Group N PossumLINK computer.

Cool units - as I said earlier, I just didn't know of larger units available in this country...nobody ere offers anything. However, those are way verkill for 450 crank hp....and of course, good luck ever getting the car to ilde again at anything less than 1000 rpm....for me, no big deal..hell, we have to idle my Datsun at about 1400 just due to the cams and large injectors in there...but for a street car, its a bit annoying.

Jan - what do those injectors cost? Anything a bit smaller? Are they an OEM unit bored out by PE? thanks!

EatMyAWD - cool...which fuel pressure regulator though are you running, or plan on running...you just need to make sure you can flow enough rail pressure to support these new injectors, and also keep the pump happy.

The Power Enterprise 850cc injectors are the only ones available in Japan as bolt-ons I'm lead to believe. I have access to PE 210L/hr fuel pumps (very quiet) and another shipment of the PE1818 and PE1820 are on the way from Japan. The injectors are costly at US$690 (+shipping). What you see in the photo is what you get as a complete kit.

For Fuel regulator, I personally run a Sard unit, There's an additional port to which you can attach a gauge but i monitor fuel pressure via a separate Sard Fuel pressure gauge and supplied sensor. Idle is 3 kg/cm², on full throttle fuel pressure hit slightly over 4 kg/cm².