1600cc

[blue1]

Would i run into to many problems with tuning 1600cc bosch injectors, i am running a stand alone ECU through a map sensor, These injectors are cheap to buy and will be going into a 4G64 hybrid, 1G heads up!, turbo still playing with but the aim will be approx 30 psi boost.

[kpt4321]

You didn't give us enough information, nor can we necessarily answer the question.

Maximum injector size is totally dependant on the engine management system, some system can handle injectors that big and some can't.

So, you're going to have to talk to the company that makes your system, or you can tell us what it is and maybe somebody will know.

You need a whole lot of fuel pump to support injectors that big.

[Mirage2LTurbo]

Yes, a lot of fuel pump you need. My system controls them just fine (they are actually 1680's). I pull ~1% at idle, 800rpm, 14.7:1 a/f. Some systems can't do that though, so make sure you either a)post what you have or b) call the manufacturer.

[kpt4321]

Yeah, but you need it because you run alky. This guy, maybe not so much.

[Mirage2LTurbo]

Actually no, I run regular gas. I am using 45% injector duty cycle at 1 bar, 12:1 a/f, 8500rpm. I will apex the 50% mark revving to 9000 or 9500 on 1 bar (14.5psi). Alcohol requires 200% more volume than regular gas, so if I do decide to run alky, I'll have to go to a staged injector setup, probably just add another row of 1680's

Besides, if I ran 14.7:1 a/f on alcohol, my shit would be blown the fook up.

[kpt4321]

I thought you were trying to run alcohol on that setup? Interesting.

I figured that the numbers you quoted were for gas, but you chose injectors that large simply so that you would have the capability to run alcohol is you so wished.

1600 (x4) cc/min of alcohol is good enough for what, 600 whp?

[Mirage2LTurbo]

Originally Posted by kpt4321

I thought you were trying to run alcohol on that setup? Interesting.

I figured that the numbers you quoted were for gas, but you chose injectors that large simply so that you would have the capability to run alcohol is you so wished.

1600 (x4) cc/min of alcohol is good enough for what, 600 whp?

I did originally plan on alcohol, but at 35psi, I'm going to need a lot more than 1680cc/cylinder of fuel. Basically I would just double the overall fuel cal. and that would reduce my from 12:1 to 6:1, about what I want to be at for alcohol.

If you think about it, I'm using ~750cc of injector on 15lbs right now. What kinda power is that good for I'm running good timing, 12:1 a/f

Now imagine how it's going to do on 30-35lbs :giggleslikealittleschoolgirl:

[kpt4321]

Originally Posted by Mirage2LTurbo

If you think about it, I'm using ~750cc of injector on 15lbs right now. What kinda power is that good for I'm running good timing, 12:1 a/f

Now imagine how it's going to do on 30-35lbs :giggleslikealittleschoolgirl:

Oh boy. I want a ride.

[95GSXracer]

Originally Posted by kpt4321

You need a whole lot of fuel pump to support injectors that big.

I think its worth mentioning that if he is running 1600 injectors, but really only needs say 850s, then he only needs enough pump to "support" 850s. The pump has to be appropriate for the power goals, not the injector size. Now, I dont see why anyone would buy injectors this large, even if they are cheap. More "normal" large size injectors arent that expensive these days. But if the management system can do it, go for it I guess.

[GRNDSM]

Mirage,

Do you have photos of the other (top) side of that fuel cell?

Blue,

AEM has no problem controlling 1600cc RC injectors. I do not know about your EMS, but i would think that it should also work with them.

Leon
RR

[Mirage2LTurbo]

[GRNDSM]

That is how I would have liked to have done it. Unfortunately, I can't do such instal in a hatchback. This must be in a sedan, right?

Leon
RR

[Mirage2LTurbo]

Originally Posted by GRNDSM

That is how I would have liked to have done it. Unfortunately, I can't do such instal in a hatchback. This must be in a sedan, right?

Leon
RR

[GRNDSM]

I see . So are you buidling a firewall between the driver and the fuel cell? Otherwise, it would not pass tech at any track that spots it.

Leon
RR

[Mirage2LTurbo]

Originally Posted by GRNDSM

I see . So are you buidling a firewall between the driver and the fuel cell? Otherwise, it would not pass tech at any track that spots it.

Leon
RR

Heh, it will at just about every track around here. In fact, the Ohio Valley Import series allow one of the competitors, who happens to be a moderator on here, to run this same setup

But yes, I would like to get a firewall because at larger events, it would be spotted.

[95GSXracer]

I have wondered if rather than trying to build a rear firewall which is impossible in a DSM unless you go to the roof, could you build a steel box around it with some type of a hatch door to get to the filler cap. I might ask next time I'm at the track... Otherwise I would have to mount it under the car I guess. I'd love to have a small cell in the hatch just for the race gas with a bigger fuel pump...

[highpsi93tsi]

Do what every single 5.0 Mustang hatchback dragcar does
www.fasteststreetcar.com
Look at the rules.
Or nhra.com
ihra.com

[GRNDSM]

Originally Posted by highpsi93tsi

Do what every single 5.0 Mustang hatchback dragcar does
www.fasteststreetcar.com
Look at the rules.
Or nhra.com
ihra.com

Oh, I know how it can be done, it is just the way it was done on that gray Talon does not lend itself to an easy firewall construction.

I am thinking of making the fuel cell protrude only 3-4" into the trunk (if at all), with most (if not all) of it being under the trunk.

Leon
RR

[Mirage2LTurbo]

Build a steel box around the cell as per MHRA rules, and have a removeable top with a few bolts holding it down. That is perfectly safe and track legal. Stop thinking so much

[crankbender]

I don't see how you are using that much fuel with only 17 psi of boost....I assume you have done alot to increase the breathing of the engine.

To the original poster. You may want to take a look at a pulse reducer. As you open one of those honkin things the fuel system will tend to pulse pressure.

To the comment about the fuel pump flowing for the engine not the injectors. Your fuel pump needs to keep up with the injector when it is fully open or you will have a pressure drop every time the injector opens. The injector will only flow as much fuel as it can get .

mirag: what kind of fuel rail are you running. Are you experiencing any fuel pressure degredation during those higher RPM runs? It just seems to me that you arn't getting the full use out of those injectors if you are having to use 50% duty cycle at 9k.

Have you tried tapping the flow in the return line and made sure you had flow even at wot and high RPMs?

If what you are saying is correct I will have to look into 3x1600cc injectors for what I want to do in the future.

[Mirage2LTurbo]

Originally Posted by crankbender

I don't see how you are using that much fuel with only 17 psi of boost....I assume you have done alot to increase the breathing of the engine.

To the original poster. You may want to take a look at a pulse reducer. As you open one of those honkin things the fuel system will tend to pulse pressure.

To the comment about the fuel pump flowing for the engine not the injectors. Your fuel pump needs to keep up with the injector when it is fully open or you will have a pressure drop every time the injector opens. The injector will only flow as much fuel as it can get .

mirag: what kind of fuel rail are you running. Are you experiencing any fuel pressure degredation during those higher RPM runs? It just seems to me that you arn't getting the full use out of those injectors if you are having to use 50% duty cycle at 9k.

Have you tried tapping the flow in the return line and made sure you had flow even at wot and high RPMs?

If what you are saying is correct I will have to look into 3x1600cc injectors for what I want to do in the future.

No dynos, but the buttdyno is saying 400ish+ whp on 1 bar. Keep in mind that IDC is not linear, turbo dynamics my son Trust me, I have plenty of flow. I'm only running 37psi base, which isn't really a big deal, I'll never run out of injector. If I get close, I'll bump up the base pressure and go from there, but 5psi isn't going to move my IDC anything incredible. Think about it, I'm using 780cc's of injector.. what kinda power is that good for? I have an incar fuel pressure gauge, it is fine under WOT.

1 bar is 14.5psi, not 17 I should be on 18-19 this weekend though, I'll post up how it goes

[95GSXracer]

Originally Posted by crankbender

To the comment about the fuel pump flowing for the engine not the injectors. Your fuel pump needs to keep up with the injector when it is fully open or you will have a pressure drop every time the injector opens. The injector will only flow as much fuel as it can get .

I dont understand this line of thinking at all. Wether you have a 200 lph pump or a 400 lph pump, 1600cc injectors at a given duty cycle always require the same fuel flow from the pump. I cant see how a higher flowing pump would dampen the pulsation from large injectors. I'm certainly open to a more in depth explanation if you're willing.

[burldude]

To the comment about the fuel pump flowing for the engine not the injectors. Your fuel pump needs to keep up with the injector when it is fully open or you will have a pressure drop every time the injector opens. The injector will only flow as much fuel as it can get


I think Crankbender explained this . More psi , and more volume allows the pressure not to drop when the injector opens . Supply and demand needs are met.

[markgholland]

Originally Posted by burldude

I think Crankbender explained this . More psi , and more volume allows the pressure not to drop when the injector opens . Supply and demand needs are met.

I think that they both agree that a larger pump is needed to supply the 1600cc injectors with sufficient fuel. I think it was purely a misunderstanding based on wording.
~Mark

[4SFED4]

Unless your goal is to make over 700hp I would stick with 950cc injectors or smaller. I would also try to size my injectors to supply the proper amount of fuel for X hp and stay under 75psi of peak pressure. Most high performance fuel pumps for reasonable prices cannot handle the abuse of rail pressures above 80psi and have dramatically drop in flow.

I run a base fuel pressure 22psi so I can properly regulate my fuel at idle and low engine speeds due to the TEC IIs limited fuel map(8x8). I am using an Aeromotive 4 port bypass regulator somewhat designed for carb applications with a heavier spring.

[Mirage2LTurbo]

Originally Posted by 4SFED4

Unless your goal is to make over 700hp I would stick with 950cc injectors or smaller. I would also try to size my injectors to supply the proper amount of fuel for X hp and stay under 75psi of peak pressure. Most high performance fuel pumps for reasonable prices cannot handle the abuse of rail pressures above 80psi and have dramatically drop in flow.

I run a base fuel pressure 22psi so I can properly regulate my fuel at idle and low engine speeds due to the TEC IIs limited fuel map(8x8). I am using an Aeromotive 4 port bypass regulator somewhat designed for carb applications with a heavier spring.

Need more matrix

www.autronic.com

[95GSXracer]

Larger injectors will be open for a much shorter time. No more fuel is pulled from the rail than the engine is using, regardless of injector size. If no more fuel is being taken from the rail, why do we need more flow/pressure to backfill it?

[Mirage2LTurbo]

If you are running -6 line, you are going to have to flow x volume to maintain y psi. If you run a -10 line, you're going to have to flow more fuel to maintain the same pressure.

a injector will consume the same amount of fuel as b injector, like 95GSX said, they will just be open shorter.

[95GSXracer]

Originally Posted by Mirage2LTurbo

If you are running -6 line, you are going to have to flow x volume to maintain y psi. If you run a -10 line, you're going to have to flow more fuel to maintain the same pressure.

Only in an open-ended system. In a closed system like ours (pressure regulated), the above statement doesnt apply.

[Mirage2LTurbo]

Correct. The pump only has to supply enough fuel to overcome what the injectors expend to maintain the fuel pressure.