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Discussion Starter #1
I've created a new thread specifically for this upgrade test to make it easier to find and so that it does not invade other peoples posts.

I sent a set of 327s to DieselPower (Dieselpower) after speaking to Yanko about his upgrade. I spoke to Lukas and he set about testing and modifying the injectors.

I first wanted flow data from the standard 327 injectors, so a good one was selected and run both on the standard Bosch test for generating calibration figures and on the rig at a variety of pressures and durations to allow firstly better comparison of the standard and upgraded items, and secondly for a good injection duration map to be created.

They then modified the injectors and did the same again, the results below are for the modified 327 are from the lowest flowing injector post modification, all others flowed slightly more.

Standard 327 (expected / achieved)

Backflow: 1 18.0-68.0 / 35.6
Backflow: 2 0.0-80.0 / 34.2
max val: 61.7-77.7 / 69.0
med val: 18.4-27.2 / 23.9
low val: 3.0-9.6 / 5.6
pre 1: 0.3-3.9 / 1.6
pre 2: 0.0-2.8 / 2.4

Pressure(bar) duration(us) flow(cc/min)
300 - 600/800/1000/1200 - 3.9/9.3/15.6/21.7
600 - 600/800/1000/1200 - 13.9/25.5/40.1/54.5
900 - 600/800/1000/1200 - 22.5/40.2/61.5/82.7
1200 - 600/800/1000/1200 - 31.2/53.9/78.4/105.6
1500 - 600/800/1000/1200 - 39.3/65.7/94.6/126.2
1700 - 600/800/1000/1200 - 44.2/74.9/105.1/139.4

Modified 327 (mean std 327 value / achieved)

Backflow: 1 19.9 / 39.9
Backflow: 2 40.0 / 29.2
max val: 69.7 / 85.0
med val: 22.8 / 32.9
low val: 6.3 / 7.2
pre 1: 2.1 / 3.0
pre 2: 1.4 / 7.3

Pressure(bar) duration(us) flow(cc/min)
300 - 600/800/1000/1200 - 6.1/11.6/17.6/25.5
600 - 600/800/1000/1200 - 19.8/35.8/49.7/63.2
900 - 600/800/1000/1200 - 34.2/55.9/76.2/97.1
1200 - 600/800/1000/1200 - 47.3/71.8/98.1/124.3
1500 - 600/800/1000/1200 - 62.6/90.7/119.7/147.8
1700 - 600/800/1000/1200 - 72.9/105.0/132.1/161.2
 

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Discussion Starter #2
So the average increase was around 17% increase over the standard 327s.

The mean average max flow of a 327 would be 69.7cc and the same for a 243/159 injector would be 65.2

So the 327s are approximately 6.9% more flow than the original 243/159 injectors at the max flow test for calibration, their flow above this set pressure and duration might be a greater increase though.

The modified 327 would there fore give approximately 25% more flow than the original 243/159 injectors.

I have not tested the injectors in the car yet, so can not comment beyond the rig flow data. I'm hoping the variations between injectors will be low enough to avoid any vibration issues. The biggest variation is about 7% between them on the low/med/max tests, I think that will be okay.
 

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Interesting. Variation of 7% sounds something that could be accepted. Did you check how big were the variations before modification? Is there any logic on injector calibration codes that could be used for estimating injector differences afterwards?
 

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Interesting. Variation of 7% sounds something that could be accepted. Did you check how big were the variations before modification? Is there any logic on injector calibration codes that could be used for estimating injector differences afterwards?

EDIT: Example injectors with codes BIAIDTAAA and 8Z15BT7AA might have quite different characteristics, as the engine sound like a different engine when setting these for all the injectors. These both were on one original injector in my car.
 

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Discussion Starter #5
I have been unable to find any information to allow me to generate codes, so it is a case of collecting lots of codes, starting with the same code for all and then trying different codes on any injectors showing high deviation.
 

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Interessting,

i do have a minor question regarding injected fuel and soot production.

What does generate more soot (assuming the same amount of fuel in total would be injected).

a: inject more fuel in a shorter injection window (short duration)
b: use a wider injection window and longer duration


?

And somehow one should manage to code these, otherwise it would be a PITA to get injection window rigth (i guess)....

anyway verry cool someone actually came up with uprated injectors :)
 

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Discussion Starter #8
A shorter duration started at the same time should produce less smoke, which, what I'm aiming for.

The duration values will be based on the average flow of the four injectors I have and that should work fine just like the 327s I have in now.

I ran the car on the dyno today to get some figures to compare after. The corrected flywheel estimates from the dyno were

Eco mode (90mm^3) - 218bhp / 335lbft (458NM)
Sports mode (120mm^3) - 258bhp / 393lbft (537NM)

I'm only wanting to increase the power more as the torque is almost unuseable now.
 

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Discussion Starter #9
The injectors are in and working okay but there is noticeable vibration from 2000-3000 currently.

I will try various codes to see if I can get a smooth runner but clearly they are not close enough in balance at the low to medium range.

On the positive side, they idle fine without smoke and I held it at 4500rpm in neutral and there was no smoke. This means the low end fueling is as per the flow data, as per standard.

I do think it pulls harder but without measurement this could be just in the head.
 

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Discussion Starter #10
Finally got my gps data logger working again and found I was about 40bhp down on what I had with standard 327 injectors.

I increase and decreased injection timing and found I could get a lot more but still not as much by significant advance of timing, to levels I was not comfortable with.

On studying the logs I found that though common rail demand was 1600+ bar, the achieved pressure was about 400 bar below. So clearly the current pump is no where near capable as it is dropping off by 3000rpm.

I will look for and fit an R80 pump, hopefully I'll be able to get some power out of them then but I need to collect injector codes AND flow data to find suitable calibrarion codes.
 

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Hmmm.... pump issue or are modified injectors leaking too much back to the return line?
I would guess this is not a pump related issue...
 

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Discussion Starter #12
The back flow figures were measured on the Bosch calibration rig and were all well inside the limits of a standard 327 injector. Unless they gave me false figures then there is no reason that it should be related to the leak back. It only occurs above 3000rpm under load, at lower IQs it can maintain high rail pressures at high revs happily.

Even with the standard 327s the pump struggled to keep up at top end.
 

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Discussion Starter #13
Fitting the R80 pump has done the trick on the fuel pressure front, now able to hold and exceed demanded pressure at 120 IQ. I pushed it up to 130 IQ and the pump is starting to lag a bit again though, so I'm looking for a compatible R90 or bigger.

After collecting a lot of calibration codes along with the accurate values of the injectors from the Bosch rig, I was able to get the balance of the injectors close enough to now make some good power and make my clutch smell like a burning tyre.

I don't think I have the sort of increase I was hoping for but I will stick it on the dyno again and see. Results from the GPS box suggest maybe 10bhp more.
 

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Discussion Starter #15
I've not tested the 341s and haven't been able to get flow data for them. If the 341s flow 20% more than stoke 243s, these modified 327s are flowing 30% more than and average 243 according to the Bosch standard test but in the broader flow tests upto 1700 bar they were 26% above 243s.

I'm happing with my mapping for them now but need to get them calibrated better. I need codes along with the correct flow data for them.

For example

0 445 110 243
A8ISH6EAA

High (57.2-73.2) 58.3
Med (16.6-25.4) 22.3
Low (2.0-8.6) 4.3

By calculating each as a percentage of the range and plotting as a line graph, I can compare a large number of codes to fine ones that are suitable but without the flow data, the codes are useless.
 

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Discussion Starter #18
A friend of mine has just dynoed on one of my maps and achieved 246.5 at the road wheels with dyno stated flywheel figures of 292bhp / 600NM.

He has less fuel flow than me but rather than my GT1858, he has a GTB2260. He also hits peak torque at just 2700rpm.

I'm happy for him but a bit jealous, especially as it is my mapping XD

This has made up my mind once and for all to fit a GTB2260 to mine.
 

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Discussion Starter #20
The extra water feed and the additional cost of acquiring one of those units puts me off. The 2260 I'm looking for can be acquired for £300 and all the rest of the parts I have already and can fabricate anything needed for the vacuum conversion.
 
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