I am installing my single t04s with 850s and 1600s. I was wondering if it would be better to go with injector dynamics 1000cc in the primarys and secondarys instead. I wouldn't have to wire in the FJO injector driver and from my understanding the ID injectors are far superior to the older style that i currently have. Would 4 1000s give me enough fuel? I really dont want to step up to the 2000cc injectors as they are double the price. I plan on running 15psi but would like the ability to get in the 20-25psi range if need be.

 

4 1000cc injectors won't be enough for 20+psi. You will incur a lot more bigger expenses running 25psi than the difference in price on id2000s..

 

Your 850s and 1600s will be fine.Alittle alky spray will add some extra fuel for headroom and cool like a bitch

 

I agree!

 

i have a t04z with 850 and 1680 bosch injectors, i run 12 psi but an gonna step it up to 14-15 and re-tune in the spring...i have more than enough fuel-.......4-1000's would be hard to tune idle. you could go id750 and id2000 would be the latest and greatest. but for 15 psi you will have plenty of fuel wither way!

Drew

 

Assuming that your turbo has 60-1 wheel which at choke flows 65 lbs/min, AFR 10:1 and relative fuel density of 0.7, 4x1000cc theoretically could support it, but high rpm operation limits pulse width and it doesn´t account for dead times and minimum time between pulses for linear operation, so for proper operation, you would have to use higher base pressure.
According to Injector Dynamics HP calculator, at least 75 psi base pressure would be needed to max out your turbo and assure linear operation at high engine speeds.

Obviously, you would need fuel pump that can support that much flow at such high total pressure - bosch 044.

Also, such setup wouldn´t have room to grow, ultimately bigger injectors will be needed for more power.

 

Yea I know the 850/1600s are more than enough i just hate the idea of splicing in the FJO driver in but i guess to save 400 dollars i should just go a head with my set up. I have a 2 stage snowperformance AI kit. I was planning on placing both injectors post turbo but what are you guys thoughts one placing the first stage injector pre turbo and the second stage post turbo? I haven't done too much research on placement. What about the meth/water mixture corroding the wheel?
Thanks for all your input.

 

You need the 1600/850's.... the 4x1k WILL NOT support high boost. to keep your afr's @11.0 and injector duty in the controllabe area .
I previously ran my T04s to 25PSI, I also needed to add a second walboro/2nd feed to keep up, granited im a drag race but better safe then 4k rebuild, 2k turbo... just to save a few hundred.....

 

I'm always wondering why in the US you always need a lot of fuel when in the Japan you don't need that much (I know they have 100 octane but still...).

Fam Speed, Re-Amemiya, FEED, they both used 4x850cc with T04S/R without any trouble as far as I know. I know it's old school, but if it has been working for years on their cars ...
(And yes, I know about the usual crappy idling, the headaches when tuning about the 4x850)

 

....one reason is those ridiculously high BSFC's that we insist on running--which is likely the primary reason for that "bad" rotary efficiency rap.

The other reason is that they're making less power. According to my calculator, 4 x 850 should support in the neighborhood of 51#/min or 450 bhp.

4 x 1000 should idealy support around 530bhp or about 61#/min of air. (At 25PSI boost cited, the airflow could be around 62#/min.)

The foregoing assumes a 0.6bsfc, a base fuel pressure of 43psi, that you can maintain adequate fuel pressure at all times, ~11.5:1 afr and a max IDC of about 80%.

 

4x ID 1000 and 430whp at 15psi(but on e85)

http://www.youtube.com/watch?v=BLWzc...72AHT1BD9wAFAA

 

Again, considering peak flow of turbocharger 65 lbs/min, very rich AFR 10:1 and very low relative density of fuel 0.7, static flow rate of injector would have to be 1054cc. Now accounting max duty cycle of 90% (which according to ID is managable at 8000 rpms) we need 1170cc. And according to the spreadsheet bellow, its easily achieved at 60psi delta pressure, so there is no reason why it shouldn´t work. Just pump has to keep up.

 

Running at the theoretical limit is a recipe for disaster, especially when running high boost, DO IT RIGHT OR DONT DO IT AT ALL....

So Pray your injectorys operate as the day they rolled off the factory line, pray your fuel is 100% as consistent as the day you dyno (winter/summer blends) change your fuel filter with ever oil change so you never have any taper in your fuel supply, hope that you dynoed on a cold day or your tuner built you maps with proper fuel correction for cold air temps, with rotaries "Just enough" is a bad idea.....

 

65 pounds per minute (at 18 psi) ...

940 CFM / 1.92 = 489 MAX rw rotary SAE hp.

65 pounds of air at 10 to one AFR is 6.5 pounds of fuel.

6.5/ 6.35 = 1.023 GPM gasoline = 3872 CC/Min

3872 X 1.176 to correct for 85% max duty cycle= 4553 CC/Min

4553 X 1.12 to add for dead time = 5099 CC/Min Nominal Gross delivery

assumes you want to be able to tune down to 10.0 AFR, run no more than 85% duty cycle and have 12% lag/dead time.

the Bosch EV14/ID injectors can run to 8 Bar. (116 psi) so as mentioned above you can up the fuel pressure assuming your pump will perform. flow increases w the square of the increase.

65/43.5 = 1.494. Sq root is 1.22, so you would up your flow by 22% by running 65 pounds static pressure.

4000 X 1.22 = 4880 close enough

this assumes you have the 60-1 comp wheel 2.32 X 3 and not the TO4r 2.62 X 3.3 which is an entirely different (larger) animal.

BTW the compressor map on the 60-1 shows max flow at just under 18 psi. up the boost further and get less air.

hc

 

But isn´t this the same regardless of fuel pressure and injection capacity? There are many possible ways to build safeguards for loss of fuel pressure, but do people use them? I guess the answer is no.

Second thing, I didn´t calculate theoretical limit, I´ve used very conservative numbers and this scenario will only happen at peak of powerband on maxed out turbo. Third thing, in the end it doesn´t matter what pressure you run, consequences of failures or irregularities of fuel system components will be same. Almost no body has ECU which would use individual wideband sensors to modulate pulsewidth when injector gets dirty or when fuel pressure is not up to task. So the whole point is moot.

I´m certainly not arguing that its better to be safe than sorry, but OP asked, if its possible to run 4xID1000 injectors and high boost on his current turbocharger and answer is yes, if his fuel pump can manage slightly higher pressure than what is/was considered as standard in this industry.

 

Yes it would work but why would you willingly take fuel away? The same fuel set up, injectors, driver, ect... has been used countless times and been pretty damn consistent. I understand the simplification aspect but when it comes to food for your motor, you want that bitch to be able to eat like a whale even if it doesn't necessarily need to.

 

Forget about the fuel--I want to know how to get 65#/min of air through a 13B at 18psi manifold and say a realistic 49 deg C IAT.

According to my trusty calculator: at 7500rpm, 18PSI manifold, 49*C and 100% volumetric efficiency, you can only get about 52#/min through the engine.

If you want to move 65# through our engines, you must up the boost to ~26PSI (or increase the VE to 125%), all else being equal. At this level, one might expect to see approx 575 bhp (11.3:1 AFR and a BSFC of 0.6#/hr/hp).

Further digression....

Now take 575 bhp and divide it by the "special" 489 MAX rw rotary SAE hp (shown above) and what do we get? 1.1763 (or its reciprocal, 0.85) Hmmmm. Looks pretty typical to me for [drivetrain] losses, maybe a little high--but probably not by much. The point being, this incongruence really makes me wonder about the popularly held perceptions vs. reality when it comes to the so called rotary inefficiency. Some food for thought.

 

"I want to know how to get 65#/min of air through a 13B at 18psi manifold and say a realistic 49 deg C IAT."

there clearly are spots on compressor maps that our engines cannot reach. take a GT45 and look all the way to the right and there is alot of unreachable territory. i was not necessarily stating that the max spot on the 60-1 map was reachable but was assuming for purposes of fuel system design that it was. (prepare for all eventualities)...

that said, i am trying to understand your calculations... BTW, i am NOT questioning them, just trying to understand.

there are lots of ways to find answers... we may be doing it differently. what i do has generally worked.

of course a rotary will accept 65 pounds of air at 18 psi if the ports/manifolding are optimised.

65 pounds is 940 CFM and 489 SAE rwhp. note the guy above who made 430 at 15.

430 is 825 CFM or 57 pounds.

18/15 = 1.2 X 57 is 68 pounds. this assumes the turbo can be driven to the far right at 18 psi.

"According to my trusty calculator: at 7500rpm, 18PSI manifold, 49*C and 100% volumetric efficiency, you can only get about 52#/min through the engine."

i have a dyno run that i did Jan 16 at 18 PSI. i made 434 SAE rwhp. 434 X 1.92 = 833 CFM/ 14.471 is 57.6 pounds of air. so according to your method i must be above 100% efficiency. and actually i was a bit short on power due to some other considerations. i believe turbo'd apps run above 100%...

i do note you mentioning 49 C IAT. while i understand the connection w oxygen molecules per volume of charge air i sure don't ever run anywhere near that number. my IAT runs between 19 and 27 C at 26 psi.

just for some additional data i did a BSFC calculation from a recent run.

349.8 pounds of fuel made 600 Flywheel (SAE) hp. (11.45 AFR, 20 C IAT, 7237 rpm)

58.28 BSFC.

hc