Does anyone know about injectors?

[TheAngryDog]

I have purchased a Supercharger kit for my car but the injectors usually supplied by them are NLA, which is annoying.

I am trying to find a suitable alternative to use, that will also give me some headroom.

The injectors in my engine currently are these:

Bosch 0 280 158 036
12 ohm
Static flow rate at 3bar is 192.9g/min
264.8cc/min
EV14
4 holes in the nozzle.

The ones that usually come with the kit are these, which are an Audi TT 225 injector:

Bosch 0 280 155 892
12 ohm
Static flow rate at 3bar is 269g/min
386cc/min
EV14
4 holes in the nozzle.

I have seen a similar injector, which are from a Ferrari 599:

Bosch 0 280 158 124
12 ohm
Static flow rate at 3bar is 261.1g/min
390cc/min
EV14
12 holes in the nozzle.

And these are from a Porsche 911 Turbo. They're much larger but give some headroom, as there are thoughts they the Audi injectors may run a little leaner than preferred at the top end:

Bosch 0 280 158 123
12 ohm
Static flow rate at 3bar is 429.2g/min
627cc/min
EV14
6 holes in the nozzle.

I am aware of latency, this can be mapped around.

If anyone has any experience around injectors then I'd greatly appreciate it.

Thanks.

[GreenV8S]

Go as big as necessary and no bigger. The higher the injector flow, the harder it is to control fuelling under very low load conditions such as at idle.

Keep an eye on injector duty cycle while it's being mapped to make sure you have enough headroom for all the enrichments.

Make sure your pump and pressure regulator are able to deal with the additional flow.

If you're using manifold pressure referenced fuel pressure, make sure the pump and regulator can cope with the additional pressure too.

[TheAngryDog]

Thanks for your reply.

Yeah I am concerned about going too large. I guess the issue I have is the leanness at the top end. Some people think it is the fuel pump that doesn't deliver enough, some think injectors.

I plan to replace the fuel pump with a walbro unit at some point.

[SturdyHSV]

TheAngryDog said:

Thanks for your reply.

Yeah I am concerned about going too large. I guess the issue I have is the leanness at the top end. Some people think it is the fuel pump that doesn't deliver enough, some think injectors.

I plan to replace the fuel pump with a walbro unit at some point.

Rough (and safe) rule of thumb is the GPH flow rate of the pump x 10 gives a rough hp figure it'll supply. I don't know what the stock pump flow rate is, but should be possible to find out? I have a DW300C in mine as it's a drop in replacement, might be the same with yours? Or a DW300, that's the same pump just physically a little taller? That's ~84gph at 40psi, they say that'll do over 1000hp at 43psi, so the rule of thumb is very conservative.

It's always nice to see what the OEMs do in these sitautions and what people find when modifying them. The LSA makes high 500s from the factory (only 8 cylinders, but also supercharged at least so perhaps similar fuelling demand ultimately) and comes with 56lb injectors (~600cc). These injectors are generally fine until pushing 650hp or so at which point people upgrade. OEM fuel pressure is 58psi with the LS.

In conclusion, I think if GM were making your engine to live with a supercharger at 700bhp, they'd use the same LSA injectors, as it ends up with a similar amount of work (in terms of horsepower produced) per injector, and for future goals, you'd be over 800 before you got to the equivalent ~650bhp upgrade point people find.

So my totally random uneducated guess would be go with the 600cc jobbies, and I don't think you'll be having any idle / driveability issues given an OEM is happy to use such 'big' injectors and happily pass emissions etc. on a single throttle body, significantly less sophisticated engine.

Edited by SturdyHSV on Wednesday 12th April 16:46

[stevieturbo]

TheAngryDog said:

I have purchased a Supercharger kit for my car but the injectors usually supplied by them are NLA, which is annoying.

I am trying to find a suitable alternative to use, that will also give me some headroom.

The injectors in my engine currently are these:

Bosch 0 280 158 036
12 ohm
Static flow rate at 3bar is 192.9g/min
264.8cc/min
EV14
4 holes in the nozzle.

The ones that usually come with the kit are these, which are an Audi TT 225 injector:

Bosch 0 280 155 892
12 ohm
Static flow rate at 3bar is 269g/min
386cc/min
EV14
4 holes in the nozzle.

I have seen a similar injector, which are from a Ferrari 599:

Bosch 0 280 158 124
12 ohm
Static flow rate at 3bar is 261.1g/min
390cc/min
EV14
12 holes in the nozzle.

And these are from a Porsche 911 Turbo. They're much larger but give some headroom, as there are thoughts they the Audi injectors may run a little leaner than preferred at the top end:

Bosch 0 280 158 123
12 ohm
Static flow rate at 3bar is 429.2g/min
627cc/min
EV14
6 holes in the nozzle.

I am aware of latency, this can be mapped around.

If anyone has any experience around injectors then I'd greatly appreciate it.

Thanks.

Bog standard stuff, just call ASNU

https://www.asnu.com/injectors

And obviously you will need your ecu re-tuned to suit any new injector.

[stevieturbo]

TheAngryDog said:

Thanks for your reply.

Yeah I am concerned about going too large. I guess the issue I have is the leanness at the top end. Some people think it is the fuel pump that doesn't deliver enough, some think injectors.

I plan to replace the fuel pump with a walbro unit at some point.

There's no thinking or guessing to be done.

Log fuel pressure and injector duty and see what is not behaving as it should

Choose based on facts.

[TheAngryDog]

stevieturbo said:

TheAngryDog said:

I have purchased a Supercharger kit for my car but the injectors usually supplied by them are NLA, which is annoying.

I am trying to find a suitable alternative to use, that will also give me some headroom.

The injectors in my engine currently are these:

Bosch 0 280 158 036
12 ohm
Static flow rate at 3bar is 192.9g/min
264.8cc/min
EV14
4 holes in the nozzle.

The ones that usually come with the kit are these, which are an Audi TT 225 injector:

Bosch 0 280 155 892
12 ohm
Static flow rate at 3bar is 269g/min
386cc/min
EV14
4 holes in the nozzle.

I have seen a similar injector, which are from a Ferrari 599:

Bosch 0 280 158 124
12 ohm
Static flow rate at 3bar is 261.1g/min
390cc/min
EV14
12 holes in the nozzle.

And these are from a Porsche 911 Turbo. They're much larger but give some headroom, as there are thoughts they the Audi injectors may run a little leaner than preferred at the top end:

Bosch 0 280 158 123
12 ohm
Static flow rate at 3bar is 429.2g/min
627cc/min
EV14
6 holes in the nozzle.

I am aware of latency, this can be mapped around.

If anyone has any experience around injectors then I'd greatly appreciate it.

Thanks.

Bog standard stuff, just call ASNU

https://www.asnu.com/injectors

And obviously you will need your ecu re-tuned to suit any new injector.

I actually contacted ASNU earlier. They have a 630cc injector that is similar to standard. They don't have the specs available though to see how compatible they are in terms of scaling and latency.

[Boosted LS1]

Have you worked out your HP requirements? If so, find injectors that can supply enough fuel for that plus some reserve headroom.

[TheAngryDog]

HP requirements are 680bhp which is what the kit is geared to. I'd like 700bhp but I think that would need more boost.

When I use a calculator based on 3 bar pressure, the injectors supplied with the kit are basically being maxxed out at 100% duty cycle to make the power.

At this time I don't know what fuel pressure my car runs.

[E-bmw]

I don't know if the kit is designed to do it or not (obviously) but 3bar is a F-load of boost, are you sure that is right?

[SturdyHSV]

E-bmw said:

I don't know if the kit is designed to do it or not (obviously) but 3bar is a F-load of boost, are you sure that is right?

3 bar fuel line pressure, just what is used when giving injector flow rates as a bit of a standard.

[GreenV8S]

TheAngryDog said:

At this time I don't know what fuel pressure my car runs.

In that case you should probably delegate this decision to the person who's going to calibrate the engine management system for you.

[Boosted LS1]

TheAngryDog said:

HP requirements are 680bhp which is what the kit is geared to. I'd like 700bhp but I think that would need more boost.

When I use a calculator based on 3 bar pressure, the injectors supplied with the kit are basically being maxxed out at 100% duty cycle to make the power.

At this time I don't know what fuel pressure my car runs.

You could fit an inline adjustable fuel pressure guage.

[stevieturbo]

TheAngryDog said:

HP requirements are 680bhp which is what the kit is geared to. I'd like 700bhp but I think that would need more boost.

When I use a calculator based on 3 bar pressure, the injectors supplied with the kit are basically being maxxed out at 100% duty cycle to make the power.

At this time I don't know what fuel pressure my car runs.

It runs whatever fuel pressure you set it to run.

And as already stated, you will need to retune the ecu for any injector swap. Period.

And size injectors so you are running around 80% duty at maximum effort.

You do not mention how many injectors you are using, but when you state the TT injectors and a few others which are pretty small, it must be a lot for the claimed power goals. Either that or something isn't adding up
because no way 4, 6 and not even 8 will be doing it safely with only 380cc.

[Dave.]

They’re for his M5, so he’ll be needing 10 of them.

PS, Mike, the s miss you, come back!

[stevieturbo]

Dave. said:

They’re for his M5, so he’ll be needing 10 of them.

PS, Mike, the s miss you, come back!

Then the likes of the very common Siemens 600cc ( go by various designations in and around 600-660cc ) would work well, and they're quite happy at higher pressures if you needed to bump them up a bit.

However......there are probably more fakes of these out there than genuine, so buy carefully.

Or just buy some 6-800cc from ASNU and job done. Life is easy.