mumzer

Avoiding an argument about whether or not this can be achieved, what are the collective thoughts regarding Injector requirements for these motors to produce 460 BHP.

my thoughts are that a 42lb injector, at the BSFC we are likely to have suffering with fuel as an antidetonant, will support approximately 85 hp at 3 bar of line pressure...with the additional enrichment provided by vaccum removal and boost applied to the regulator, maybe that gets us to 100hp per injector, but that seems like a stretch of the math.

Id like the gorups thoughts on this...i see some pretty enthusiastic claims about what a stock injector, or even the 42lb bosch will do...id like to only buy them once.

thanks

Paul Bloomberg

I have made 329WHP w/3 bar reg.,stock injectors,K27, MAF and 19-20psi for the last 2years. No problems!
Now 400WHP w/2.5 reg.,550cc inj. 25psi w/ Technodyne turbo and most important tuning with a dynojet by someone who knows what they are doing!
Paul

Danno

yeah, I say at least 65lb/hr injectors for around 400rwhp. What kinda fuel-pressure & duty-cycle are you pushing Paul?

I think Alan C., Russ Murphy & Rage2 can give some info about their injector experiences.

Steve Lavigne

Are you going to use the standard Motronic or an aftermarket engine management system? (i.e. batch or sequential injection?)

[quote]Originally posted by mumzer:
<strong>... 3 bar of line pressure...with the additional enrichment provided by vaccum removal and boost applied to the regulator...</strong><hr></blockquote>

As an aside, I believe that the standard bosch fuel pressure regulators utilize vaccum/boost to provide a constant pressure differential between the fuel rail and the intake manifold. So, regardless of the intake manifold pressure, a specific duty cycle should always emit the same volume of fuel. This of course would not be the case if you chose to utilize a rising rate fuel pressure regulator.

rage2

I'm using a 3 bar fuel pressure regulator, 72# injectors, about 90% duty. With 55# injectors, I'm guessing you'll need a rising rate FPR, and close to the 100% mark.

Alan C.

I'm using 83 lb. injectors coupled to a Weldon fuel system controlled by a Tec3. At around 370 to the rear I see 80% duty cycle. At 400 the duty cycle will go up.

Alan C.

Konstantin

check my site <a href="http://www-public.tu-bs.de:8080/~y0003315/951tuning1.html" target="_blank">http://www-public.tu-bs.de:8080/~y0003315/951tuning1.html</a>

and

<a href="http://www-public.tu-bs.de:8080/~y0003315/dyno.html" target="_blank">http://www-public.tu-bs.de:8080/~y0003315/dyno.html</a>
sorry it is in German but you can see the power at the wheels about 410 HP with 52 lb Injectors and adj FPR big Turbo and MAF.
the AF ratio is there too.

Konstantin

mumzer

ok...so we have established that the injectors need to get a lot bigger.

other than the bosch 52lb and the siemens 55lb, who makes compatible peak and hold injectors for our cars?

what kind of idle quality can i reasonably expect.

im running an autothority MAF with custom chips...the car starts running out of fuel at 5000 rpm at just over 1 bar

Alan C.

Tyr these guys:

<a href="http://www.injector.com/fuelinjectors.htm" target="_blank">http://www.injector.com/fuelinjectors.htm</a>

I bought my 82 lb. units from them. Reasonable price and they are matched sets. Good customer service too!

Alan C.

David Floyd

Yes, Alan C is right, Injector.com has good prices and service. I bought 72lb injectors for my new engine.

<img src="graemlins/burnout.gif" border="0" alt="[burnout]" /> <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />

marksportcts

Can you really run injectors above 55# safely on the factory fuel injection system? I was told that even with an MAF and fuel controller, the injectors are still open too much. And are these track cars or street cars?

David Floyd

Mine is a street car, some have told me that 72lb will work and some have said I will have idle problems even with MAF, once back together we will see.

86944turbo

I use Bosch injectors. They are part number 911. They are no longer being manufactured. They are a particularly good injector from the standpoint that they can hold well over 5 bar of fuel pressure, they have very good fuel atomization and they do not drip, so they allow the motor to idle comfortably. They are rated at 83 lb/hr. @ 3 bar pressure. The static fuel pressure is at 5 bar. Under boost, 6.5 bar or thereabouts. These injectors, if you can find them are probably well over $300 each.

David Floyd

86944turbo, when will you know if you made the cut for the Sport Compact contest.

We are pulling for you <img src="graemlins/bigok.gif" border="0" alt="[thumbsup]" />

<img src="graemlins/burnout.gif" border="0" alt="[burnout]" /> <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />


ps. what do you mean by SHEEROX ?

86944turbo

David,

I need to go and buy a recent issue of Sport Compact. My brother, God bless him, voted for my car and all the extremely high H/P cars like the s/c Viper, 1000 h/p Supra, etc. Off my Christmas list.

I wanted a license plate frame that discretely read "She Rox". My wife, God bless her, ordered a license plate of the same. It was taken and sitting in some junk yard, but DMV would not release. So, it ended up with an extra "E". SHEE ROX. I have found the plate to incite every 5L. 'Tang, Integra, Eclipse, etc. None of which, have required anything above low boost (10 lbs.)to dispense of. Sorry 'bout the dangling prep.