Can someone help find the issue from datalog?

[litebulblsc]

Hello,

I am working (slowly) with a mail order tuner. It is for a free re-tune, which is why it is slow going. I sent them the first datalog, and evidently it is way out from what they expected.

They first thought it might of been a vacuum/ boost leak, so I bought a smoker and could not find anything.
Then they were asking about the fuel system, which I described it back to them and waiting on a response back now.

Vehicle info:
2004 Sierra 1500 4x4
wired up "stand alone"
6.0l lq9
4l80e trans
2.9l Whipple supercharger
ported heads
1.875" headers
3" dual exhaust
90mm throttlebody with xlink adapter
fuel system is 63lb/hr injectors @ 43.5psi- running a boost referenced fuel pressure regulator, set at 58 psi with the line disconnected.

cam specs.

Intake Duration at .050 Inch Lift:227
Exhaust Duration at .050 Inch Lift:243
Intake Valve Lift:0.614
Exhaust Valve Lift:0.624
Lobe Lift Intake:0.361
Lobe Lift Exhaust:0.367
Lobe Separation:114
Intake Centerline:109

So if anyone can look at this, and suggest any issues that could be causing me problems- it would be appreciated.

thanks,
Josh

[hrspwr]

What is the issue you are having?

[litebulblsc]

Hello,

The issue is, the prson tuning it thinks the data is too far off. Allow me to quote them.

This is the first response I got after srndi gthrm the datalog-

"Is there any chance that you have a sizable boost leak? It is appearing as a vacuum leak outside of boost and then goes excessively rich in boost."

After that, I bought a smoke machine and hooked it up to a vacuum line to make sure everything was sealed. Afterwards I let the tuner know there were no leaks and received this in response.

"It's very strange data. Perhaps there is something else amiss. What fuel injectors are you running and are you still running it as a returnless?"


Responses are taking about 2 weeks from them, so I am trying to track down the issue myself (hopefully with help from this forum).

Thanks,
Josh

[hrspwr]

My first guess would be that the injector data is incorrect. If you have a copy of the tune I can take a quick glance at it and see how its set. PM me the tune.

[litebulblsc]

I am at work currently, but can send tune file later.

I did look at the injector flow rate table, and it had the same value for each cell- which I believe is correct. I eant to say they were calculated at 73 lb/hr?, which a calculator I found on Google seemed to agree with.

[hrspwr]

Who makes the injectors?

[litebulblsc]

I believe they are Siemens Deka

[litebulblsc]

Here is the tune file.23542

[aaronc7]

100% need to confirm what injectors you have, and then confirm injector data before really digging much further, IMO.

[litebulblsc]

https://whipplesuperchargers.com/index.php?dispatch=products.view&product_id=305

[hrspwr]

It looks like these are the injectors. I know it says 61lb but everything points to these. Here is the datasheet where you can find the flow rate:
https://www.efihardware.com/download/77/Siemens-Ethanol-Compatible-Injector-Datasheet-855-646HS

The other issue is the offsets, in your tune its set to 0 offset as voltage goes up, as you can see in the sheet it is close to 0, not 0. May have to contact the mfr and get the actual data from them so you can load it into your tune. The other issue is your pressure. These injectors are rated at 3bar and you are running 4. It essentially increases the flow from 61 to almost 71lb/hr. If you have an adjustable regulator, I would put it down to 43psi where the injectors are rated for. You dont have to, you will just have to take the extra flow into account when tuning.