OE injectors measured; 360 cc

Hi,

Couple weeks ago I let my OE injectors cleaned and measured.

OE injectors, Bosch 0280 150 450, are flowing 360cc in 3 bar fuel pressure.

They measured also flow rate in 3.8 bar and 4.8 bar.
3.8 bar = 408 cc
4.8 bar = 460 cc

Then I also wanted them to check the spray pattern of the injectors in high fuel pressure.
Injectors are good up to 5.5 bar fuel pressure in short opening times (<= 3 ms) and good up to 6.5 bar with longer than 6 ms opening times.

Cleaning and measuring was done local Bosch dealer ( best in southern Finland).

- Jari -

interesting stuff!!

With the 6ms that might be a problem at high rpm (not that I've worked it out).

Anyone know a place to service and test injectors in the UK as i need my cleaned, flowmatched and tested the cc @ 3.8Bar. I've tried Owen developments any others?

most LSUK dealers can do the cleaning and verification of spray pattern as they usually have the ASNU cleaners

whats the OE fuel pressure?
arent OE injectors on 20vt 330cc? or have I mixed something up

Hi,

Original fuel pressure (base) is 3 bar vacuum hose disconnected.

Yes, in some point the Coupe injectors were rated as 335 cc / 3 bar, but the latest Bosch "bibel" informs them to be 372.9 ml/min. Bosch don't use the value ml/min = cc anymore as a floe rate value. They are taking about g/min, which by Coupe injectors is 261 g/min and the flow rate is been measured with N-heptan, not with normal fuel.

One thing, which is very important value when we are taking about injectors is Qdyn (g/1000 pulse). Flow amount in grams / 1000 pulses. This value is in Coupes OE injector 5.48g. Second important value is how fast can the injector act, Coupe injectors has this value of 1.24 ms. Which is actually quite slow compared to many others.

For example the 465cc/3.8 bar (310 g/min N-heptan) injectors I'm using have the above mentioned values as follows:
9.77 g / 1000 pulses
0.61 ms

This thing makes it so that it is not always "just change the injectors" the way to go, but you should get you car mapped to get the best result out of them.
I guess Flea and Nigel knows this the best .

- Jari -

Everywhere I looked seemed to suggest the 20vt injectors (0280150450) are rated at 347cc@3 bar

Doing the maths on that meant that:

On a standard coupe - (220HP, 347cc, 3.0bar FPR) max duty cycle is around 71%

On a modified 280HP coupe with standard 347cc injectors and 3.0bar FPR max duty cycle is around 90%

Currently on my setup with 280HP, 347cc injectors, 3.8bar FPR max duty cycle is 80%, this is the recommended MAX.

If my calcs are right then Ross was running something like 335HP with 347cc injectors, 3.8bar FPR which meant about 96% duty cycle at max HP...

As said earlier it’s not just about the cc/min. The ms play a big part too. For example I tested a ‘normal’ set of 384cc @ 3.8Bar and they maxed out at 350BHP @ 100% duty but the standard ‘330cc’ 20VT coupe injectors can cope with 360BHP @ 3.8Bar running 90% Duty. This is probably why the cc formulas always suggest 500cc+ for our cars but most people get away with 20VT or 16VT injectors without a problem. The 20VT and 16VT seem to be very different from any normal/universal top feed injector. Well that is what I found when performing my tests. And this post from Jari has just confirmed what I need to know and that is the 20VT & 16VT are a ‘special’ injector.

Interesting stuff, it does seem that the "330/347cc" standard injectors actually flow more than stated on paper.

TurboJ you say you have shown that the OE injectors can flow 360BHP @ 3.8Bar running 90% duty, but do you think that they will be reliable long-term using that duty cycle or will you be looking to use a larger injector for a greater safety margin?

It's just something that was noticed whilst I was testing different injectors over the last re-map sessions. Wanting more cc would mean switching to 440’s but this in itself is a problem. It’s far easier/cheaper to map (live map) the car to the standard injectors @ 3.8Bar with an increased duty cycle although I cannot comment on long term reliability. I personally think 90% is the limit so anyone wanting more than 360BHP should be looking into 'other' injector strategies.

Just curious - why do you think 90% is the limit? I don't think there will be TRA/FRA jiggery pokery at that level and the injectors shurely won't overheat with that much fuel flowing through 'em?

Mark

There's nothing special about the injectors, they flow like any other bosch injectors. The problem is that the majority of calculators on the internet use a static fuel pressure but we do not so the tools are useless.

I bet if your injectors are 'maxed out' and you fitted my fuel pump or an MSD voltage booster or other DC:DC stepup you would get more out of them.

Well fair enough but what I have been testing I have been getting different results. The point is nobody I know has tested different injectors other than 20VT, 16VT & Bosch 440 on the live map.

Ya canna change the laws of physics captin!

here we go
If we're talking live map then you have no idea what the duty is as the ECU reports a relative duty not an absolute one, so if one or more compensation map is in effect or adaption then the duty you see is not the duty you get. If you throw in bigger injectors then the first thing the ecu does is when it sees the difference in lambda makes an adaption for both open and closed loop which means if you throw in 380s it may only let you run them like they were 360s for arguments sake. The only way to compare them is on a test bench or non-adaptive ecu not in the car with an adaptive ecu.

On my motec I have run std injectors, 382/16vt, 440s, 500s 750s and each time I have seen the expected increase in fuelling at the same duty. My comment about the pump and voltage is that when I switched pumps (now using an bosch motorsport '044' pump) I also got a considerable increase in fuelling with the same map on both 500s and 750s even at idle.

I could actually tell you the power level I got with each type of injector but there were other factors involved

This is the bit I don't understand - unless the pump can't supply the volume of fuel required at the pressure required (which ought not to be the case at idle) then the fuelling should only be determined by the FPR and the characteristics of the given injectors at at given duty cycle? But it seems not.

(ps - thx for the info about compensation maps on both open and closed- very helpfull!)

same principle that means you can get more air (and subsequently power) from the same boost pressure. That's why I can get 440BHP with 0.7 bar boost

But nothing is changing between the FPR (which presumably is setting the same pressure) and the injector nozzle which is squirting out more juice

I'm not doubting what you're saying here - would just like to understand it. If there's an easy way to improve the fuelling across the map then I want to know about it.

This is the bit thats wrong, right? There's a pressure drop mid-pulse or between close pulses which is reduced by an improved pump?

I am about to get a set of 16VT injectors tested and measured just like Jari has done and I will post the results up sometime next week.

I am going to test
3Bar, 3.8Bar, 4.8Bar, 5.5Bar & 6Bar on the ANSU machine.

The only problem is will testing at 6Bar damage the injectors? And will it be able to be measured because at that rate the tubes should fill up within seconds.

Is there any danger testing at 5.5Bar? & 6Bar?

the injectors are rated to 5 bar, but I would imagine there is some tolerance.

I'm running a 3.8bar FPR and as much as 2.1 bar boost, so my injectors are getting very close to 6 bar.

Intresting:
http://www.asnu.com/videos.htm

OE 16VT injectors cleaned and measured:

3.0 bar = 390cc
3.8 bar = 450cc
4.5 bar = 490cc
5.5 bar = 540cc
6.0 bar = 550cc

Good stuff, what injectors are you going to try? Is it right that PT don't want to map with 440cc injectors?

I maxxed out the Siemens 384’s at 352BHP @ 5250rpm it starts to creep towards 13.5 AFR

I'm going with the 16VT injectors as Nigel has them and they fuel for the power I need. I can't answer weather PT will map another car with 440's but when I asked rob which out of the two he said go for the 16VT ones.