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brettzo007

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What about the bolts on the header collectors? I heard others with this problem.
Those have been checked thoroughly and tightened. There is no play/rattle.
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dubster99

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If my knock is indeed false, it only appears when the return fuel system is running fuel. It's still in the car outside of the pump and the return line off the fuel rail. What about those is going to cause knock if not the tune? Again, it's either tune, bad 350 pumps from Sai (that start and idle the car just fine independently) or FPR. Literally only options.
If the fuel system/pumps was bad for any reason, you'd see that in the logs too. Can't wait to put my return system in when I get time and fire up my PBD tune.
 
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brettzo007

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Here's a log from the other day. 9.99* max retard in this log in first gear around 6000rpm, up from what used to be around 3-5*. This is after deleting header cats (one was rattling when pounding on it), removing AC bracket bolt and checking the entire car over. I just don't get it anymore. Going to try some Octanium again today to see what happens, but what a slug as it currently stands.

Wondering if my suspension mods could also be playing a role in this (vertical links, subframe brace, IRS busing set)?

https://www.dropbox.com/s/pztov0yv00vcbaw/datalog1 sept 7 wot.csv?dl=0

In watching this video, does anyone know whether multiplying MAF flow rate x 10 as explained at 7:06 would provide a pretty good flywheel HP estimation?

[ame]
 
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UPDATE: I re-flashed back to stock and then the most recent Lund revision today and knock for the most part is gone and timing is being added in most instances. The car feels significantly better today after the changes noted earlier in the thread completed a couple of days ago. I just drove for over an hour and night and day difference. The car actually pulls now, hard, compared to a slug yesterday with 9.99* being pulled on almost all WOT pulls.

Changes that helped to rectify:

-Remove AC bracket mount bolt (there were signs of contact with headers). Instead of trimming the bolt, I removed it and zip tied to completely rule out the possibility of it making contact again in future.
-Removed header high flow cats. When pounding one of the cats with my hand while under the car, there was a strong rattle noise present. When removing the cat and inspecting inside the piping, the cat was loose and moving around slightly. It was failing and I'm glad it's now off, especially with boost.
-Tighten all exhaust connections, trans mounts, inspected motor mounts - all were good.
-Flash back to stock/re-flash Lund tune to car.

For now my issue is gone and as several others have been experiencing this, I thought I would share. The AC bracket bolt and rattling cat is what I suspect were the culprits. After fixing all of this and re-flashing the tune, things seem to have completely resolved after completing the above changes.

Hoping this helps others...I will be monitoring/logging the car closely to ensure it's gone for good, but man do I feel good at the moment after several weeks of troubleshooting this. Knock sensors have not been desensitized and the same tune that was previously showing 4 to 9.99* retardation is now running much better.

2 logs from today below. Night and day difference from a knock perspective performance/feel of the seat. No more hesitation when accelerating, aside from a couple of blips here and there when changing gears, but then goes back to adding timing. This is the exact same fuel and tune that I had logged in my previous post, only difference being a re-flash after the changes made.

Log 1: Idle and WOT
https://www.dropbox.com/s/rhcr0pa27jpittk/datalog1%20sept%209%20idle%20wot.csv?dl=0

Log 2: Idle, WOT and a bit of cruise
https://www.dropbox.com/s/qivpogqurwfpsos/datalog1 sept 9 wot and cruise.csv?dl=0
 
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ProChargerTECH

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UPDATE: I re-flashed back to stock and then the most recent Lund revision today and knock for the most part is gone and timing is being added in most instances. The car feels significantly better today after the changes noted earlier in the thread completed a couple of days ago. I just drove for over an hour and night and day difference. The car actually pulls now, hard, compared to a slug yesterday with 9.99* being pulled on almost all WOT pulls.

Changes that helped to rectify:

-Remove AC bracket mount bolt (there were signs of contact with headers). Instead of trimming the bolt, I removed it and zip tied to completely rule out the possibility of it making contact again in future.
-Removed header high flow cats. When pounding one of the cats with my hand while under the car, there was a strong rattle noise present. When removing the cat and inspecting inside the piping, the cat was loose and moving around slightly. It was failing and I'm glad it's now off, especially with boost.
-Tighten all exhaust connections, trans mounts, inspected motor mounts - all were good.
-Flash back to stock/re-flash Lund tune to car.

For now my issue is gone and as several others have been experiencing this, I thought I would share. The AC bracket bolt and rattling cat is what I suspect were the culprits. After fixing all of this and re-flashing the tune, things seem to have completely resolved after completing the above changes.

Hoping this helps others...I will be monitoring/logging the car closely to ensure it's gone for good, but man do I feel good at the moment after several weeks of troubleshooting this. Knock sensors have not been desensitized and the same tune that was previously showing 4 to 9.99* retardation is now running much better.

2 logs from today below. Night and day difference from a knock perspective performance/feel of the seat. No more hesitation when accelerating, aside from a couple of blips here and there when changing gears, but then goes back to adding timing. This is the exact same fuel and tune that I had logged in my previous post, only difference being a re-flash after the changes made.

Log 1: Idle and WOT
https://www.dropbox.com/s/rhcr0pa27jpittk/datalog1%20sept%209%20idle%20wot.csv?dl=0

Log 2: Idle, WOT and a bit of cruise
https://www.dropbox.com/s/qivpogqurwfpsos/datalog1 sept 9 wot and cruise.csv?dl=0

Congrats on finding it!!!!!

My buddies BONE STOCK GT350 just recently ate a set of cats, and it would log 10 degrees of knock, and was a slug as well.

He replaced them, and now the car is a monster again.



Great news for everyone on how you found your issue! :)
 

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In watching this video, does anyone know whether multiplying MAF flow rate x 10 as explained at 7:06 would provide a pretty good flywheel HP estimation?
Its a really good way to get a rough idea on HP.

Remember a LOT of factors dictate HP, like timing, cam timing, fuel octane, etc.

If your tuner dials in the cars ability to understand TQ.
You can log TQ and THAT is really close because of how it takes in account more than airflow. ;)
 
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brettzo007

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Load is still falling off periodically based on logs. They feel I have a boost leak, or a belt tension problem. The belt is definitely tight and all hose connections are sturdy. Anyone know if the black bypass value could be leaking? Before the install I had looked inside the valve and did notice some gap around the flap and wondered how it wouldn't leak. Race bypass valve a good option? Have read mixed reviews on the new version.
 

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Before the install I had looked inside the valve and did notice some gap around the flap and wondered how it wouldn't leak. Race bypass valve a good option? Have read mixed reviews on the new version.
The "gap" is normal, that has about .000001% effect on boost. :)

Don't worry about that, its designed like that. :)

As long as your valve opens and closes, you are GOLDEN :)
 
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brettzo007

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The "gap" is normal, that has about .000001% effect on boost. :)

Don't worry about that, its designed like that. :)

As long as your valve opens and closes, you are GOLDEN :)
Thanks. Then I have more digging to do.
 

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How goes the knocking? I had my car retuned with AED and put down great power. Drove the car off on e85, ran at the track, trapped 138 plus, emptied tank and stored for winter on 93. FF to spring, go to run the car to the gym... knock knock.. seeing big values again like 7plus. Swap to original BAP setup and solid with no issues. I'm going to swap back to E85 now that its summer and see how she does. If there is knock I'm reverting to BAP setup permanently.
 

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Update on my knocking too... I broke two pistons. Lol. New fully forged balanced shortblock is in. Dropped compression to 10:1 and running basically same setup as before. Car pulls like a mf'r. Definitely feels stronger than before even with less compression.

Knock is gone! I mean zero, nada. Pegged on 0.00. Adding up to 8 degrees under low rpm heavy throttle. Wot it steadily adds 2 degrees to a max of around 18 total. Maf is showing just over 80lb/hr. I'm installing my fore system shortly and E85 so have to see how that goes.
 

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Any more help having same issue check exh system and all mounts I have full rear suspension and cf driveshaft just redid all the piping plus added padding to side of intercooler making contact with rebar even added padding to side where oil line is tapping frame gonna test it in the am but any help would help
 

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In watching this video, does anyone know whether multiplying MAF flow rate x 10 as explained at 7:06 would provide a pretty good flywheel HP estimation?

[ame]
No, otherwise I would be making 860 hp on my 93 tune that dyno'd at 660. The max Maf lbm per minute the MAF can read is capped at 86.68. I reach peak reading at ~6500... If his calculation was correct and I followed the line up to my shift point I would have >1000 at the flywheel on e85 and 93.
 
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Let's me get thoughts this morning ran like a monster nothing diff was done no timing was pulled but I did disable tc on the way home after work I didn't and car keep pulling timing till I then agian disable it is tc a issue for boosted cars Ie can it pull timing to prevent tire spin
 

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I'm suffering same issue up to 4.9 degrees of knock wot throttle 18 a10 vortech jt very frustrating
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