Chasing KR issues

sd-slider

NOWUFFO
Joined
Feb 22, 2009
I have been gradually working my way through the GN replacing and upgrading key components in preparation for my E85 conversion.

Mods to date current setup are:

Stock Internals
Comp 980 valve springs
RJC Stock Plenum Power Plate
TT 91 Streeter
Stock injectors
Walbro 340 w/ Racetronix Hotwire
Accufab AFPR (43 w/ vac off)
TR Custom Parts CAI w/ MAF Xlator w/ LT1 MAF
RJC 3" DP
Pypes 2 1/2 Race Pro w/ Test Pipe
HR mounts (motor, trans, and x-memeber)

Parts to be installed:
80lb injectors w/ TT E85 chip
Duttneck IC
Deatschwerks pump and new hanger, hotwire, and lines (Joe's rig from Arizona GN)

Holding off on new fuel system until I can get her running correctly before I make any major changes.

I have been chasing 5-8 degrees KR for the last year and finally went through all of the obvious connectors and components confirming everything was functioning correctly. i have also spent hours on Vortexbuicks, GNTtype, and here...trying to identify the source.

Took a little cruise around the hood last weekend and logged the trip to review and look for any possible explanations. I thought I'd throw it out here to get some feedback from those that actually know. :)

Any advice would be appreciated
 

Attachments

  • 122218-1500.dat
    1 MB · Views: 105
Make sure ALL your engine mounts are tight and have no play.

Make sure your exhaust is not hitting anywhere (also a engine mount issue)

Watch you A/F ratio
 
Thanks for the feedback. I'll crawl under there tomorrow.

The data file is from my Powerlogger.
 
Your injector duty cycle goes as high as 116 percent...and shows KR...so I'm thinking it's real. You're not logging boost...so I don't know if it's getting away on you...or the stock injectors could be clogged up. You also need to verify if fuel pressure is rising 1 for 1 with boost. Don't lay into the loud pedal until you figure this out...or you won't have any headgaskets or rod bearings. You don't mention turbo size.
 
Last edited:
In park with the engine warmed up your idle BLM's are 140. You prolly got a pre turbo exhaust leak or vacuum leak...or both. I assume you have a fresh Denso 02 sensor in it.
 
I'd say exhaust and vacuum leaks are the least of the worries. It's going lean bad when in boost. There is a fuel delivery problem.

What kind and how old is fuel pump and filter? Also what injectors?

Like mentioned, inj. duty cycle is high. Did you add a bunch of wot fuel in the chip?

And how much boost? Should try to get that tied in to the powerlogger.
 
Thanks for the feedback!

Your injector duty cycle goes as high as 116 percent...and shows KR...so I'm thinking it's real. You're not logging boost...so I don't know if it's getting away on you...or the stock injectors could be clogged up. You also need to verify if fuel pressure is rising 1 for 1 with boost. Don't lay into the loud pedal until you figure this out...or you won't have any headgaskets or rod bearings. You don't mention turbo size.

Did a ton of reading last night after my post and researched the boost logging procedure…I will be connecting the MAP signal to the analog input for boost logging in the next few days.

I also noticed the inj duty cycle spike while doing research at the same time…

Stock turbo is still on the car.


In park with the engine warmed up your idle BLM's are 140. You prolly got a pre turbo exhaust leak or vacuum leak...or both. I assume you have a fresh Denso 02 sensor in it.

I have not replaced the O2 sensor yet. I do have a new Denso on stand-by, but was waiting for the E85 conversion to install.


I'd say exhaust and vacuum leaks are the least of the worries. It's going lean bad when in boost. There is a fuel delivery problem.

What kind and how old is fuel pump and filter? Also what injectors?

Like mentioned, inj. duty cycle is high. Did you add a bunch of wot fuel in the chip?

And how much boost? Should try to get that tied in to the powerlogger.

The fuel pump is a Walbro I installed in 2010 along with the hotwire kit. Fuel filter is less than two years old.

Stock injectors are still in use with no modifications to the fuel delivery. Stock turbo is still in use as well.
 
Fuel pump is 8 years old...dollars to donuts fuel pressure isn't rising one to one with boost. Throw the new 02 sensor in...that might sort out the idle BLM...but like Rick said...that's the least of your worries now.
 
Last edited:
To me equal fuel delivery is top priority. Even if the pump is up to the task I will not leave inlectors to chance. It just takes one not being up to par and it's all over.
 
To me equal fuel delivery is top priority. Even if the pump is up to the task I will not leave inlectors to chance. It just takes one not being up to par and it's all over.

Agreed. I'd park the car and do the full upgrade.
 
Thanks again for the feedback.

I'll drop the DW300 in there and have Eric burn me a street chip to match the 80s until I can get the new lines installed with the E85 chip.
 
I would fix the issues before moving on to new mods. No sense adding new unknowns to the equation.
 
Was able to do the following the last few weekends:

- Installed DW30 pump into modified Spectra Premium hanger(extra on hand)
- 80lb Siemens squirters
- TT 5.7 Street Chip 91 octane

Confirmed Translator settings at BASE:5 / WOT 0 / ON | ON | ON | OFF
Fuel pressure set at 44lbs with line off...(lowest I could get it to go)

Been raining here for two days so I haven't been able cruise around to establish a baseline for the new injector and chip.

Hopefully Saturday will be dry enough to taker out for some fresh petrol and a cruise.
 
Was able to replace the 02 sensor and hook up the MAP signal to the PL analog input.

Took a short cruise around the hood and the results are attached. Still seeing knock when I lean into it and I have looked through the latest log data front to back and can't seem to identify any correlation...

Any advice would be appreciated.
 

Attachments

  • QuickSave-26jan19.001.dat
    574.9 KB · Views: 48
Top