Bendrick Rodriguez

Hi all,
I keep bending rods in hole 7 when I turn the boost up. I have played with timing to no avail and I can't read plugs for sh*t. Mods as follows:
2003 Ram 1500 RCSB
L33 SBE
Elgin SS2
Pac1218's
243 Heads
Billet 7875
Decapped Flex Fuel injectors, serviced by Eric Derr last year
Stock Thermostat, 190ish on highway
Stock, return style truck Rails
NGK 7bef and TR6IX plugs, Tried a colder plug to see if it changed anything
4 port stem vent
AEM UEGO LSU 4.2 style wideband
93 OCT
4L80e stock converter

Please look at the logs provided.

Story:
Had a gen 3 SBE 5.3 in the truck. I had just finished the turbo kit and wanted to see what this turbo LS life was about. Made a quick basemap and drove it. First couple of pulls I was intoxicated with how it felt, definitely wanted more buttttt... My 44mm WG was getting stuck and I was blowing through the bottom of the spark map and VE wasn't dialed in yet. After 3 days of abuse and not really playing with the tune, I bent 5 rods. It was expected and inevitable, I had my eyes set on a L33 local to me and kinda needed the excuse to pull the trigger.

Fixed the WG, (galling on the stem), installed the L33 with new cam and the old springs and drove it some more. Knowing my AFR was now good, 11.2-11.5, I turned the boost up to 14psi, where I wanted to be. Timing was pretty conservative I figured. Bent #7's rod, took it apart and slapped a new rod/piston in it. Figured, I didn't know the history of the engine, maybe that rod had a slight bend in it from a partial hydrolock at some point in it's life. The plugs looked okay, didn't show any big issues (I think) so I slapped in some new tr6ix's and drove it again.

This time I added even more fuel and took more timing out. Something was clearly still wrong with my WG or boost controller however because I wasn't still getting desired boost pressure, I had it backed all the way off (5psi spring) and still made 18.5psi! WTF!. I mean, it ripped hard, too hard lol. I purposefully added fuel and took out a bunch of timing in the event of overboost but wasn't expecting this much overboost. #7 rod bent, on that pull, it wasn't as bad as the last one but still.

So why? I can understand the LM7 and this most recent rod bend but why is it always 7 on this L33? Am I at the limit of my fuel rails? is my injector #7 misfiring or getting stuck? I do see a slight lean flicker on my AFR that seems to get worse as the engine gets hot Why is there no bending anywhere else? I get that 18psi is too much for just 93 especially with flat top pistons but I honestly had no idea boost went that high, with all the timing I pulled out of it as my safety precaution, it felt like the same power as it was 14psi with 14 degrees of timing.

I am going to have to check mechanical timing because this is so weird. I have removed the boost controller, polished and greased everything on the WG with krytox and am only running 5psi for now until this issue is resolved. I have an oscope too so I guess I should be checking my injector waveform as well.

Just had to vent in the hopes that someone will have a good suggestion or creative idea to test for issues.
AFR is logged through my AC transducer BTW.

The logs are from the first time I bent the L33 rod 7 and the second time I bent it.

I can't seem to find the LM7 file but regardless, I was fast and loose on tuning so I expected the results.

post your tune.

are you using a wideband?

Quote:

---

Originally Posted by Ecobear86

post your tune.

are you using a wideband?

---

That tune is long gone, it has been modified a lot since. AEM 4.2 Uego wideband, as stated. I have some updates as well:

Reading spark plugs:
I learned from alot of articles what to be looking for and found some answers regarding my issues in the plugs. I was definitely detonating. I have gray spectacles all over the porcelain and the ring looks a little lean on #7, see photos. It looked a little misleading because the porcelain was a little sooty when I took them out, after giving them a bath in some cleaner, the embedded aluminum showed up easily. Something about the 9.9:1 compression and 14psi is just too much lol.

Boost creep:
I had some bad boost creep due to poor WG placement and a galled up valve stem. I have since, polished them stem to a mirror finish, used krytox on the diaphragm and krytox and moly on the stem, super, silky smooth movement now, should have done this in the first place.
This didn't completely solve my issue however, I had to modify my turbo housing pipe to my WG, it might get some placement changes later if it still gives me issues.


Weird wideband behaviour:
My wideband would spontaneously indicate a misfire, it was like a spurious lean tick, if you watch those logs in 1x, you will see it (using AC transducer method for WB log) I attached a screenshot just to make it easy. Long story short, after trying a new wideband to no avail, it was injector pin corrosion on #7, fixed by reseating the injector harness adapter a few times.

In conclusion, I think it was this combination of issues that lead to #7 always bending. The high temperature of the combustion chamber accompanied with the injector not getting a solid open signal creating a lean condition and boom. Make no mistake, there was detonation on all the cylinders. Look at the plugs.


Not letting me attach anything right now, will add later.

https://photos.google.com/share/AF1Q...x5cE9GdHVpbURB

I don't know about a turbo set up but I'd say that plug looks lean. I was always told to look at the electrode. Its should have a bur / sooty line at the curve Ashy up to the curve and more white to the tip.

Just wanted to update this since I had forgotten all about it. Issue was collapsed flex pipe on the driver's side turbo crossover pipe. All has been good since the end of last summer, lots of miles, tons of pulls.

the issue was inside the flex pipe?

Attachment 98724
Yes, Imagine what exhaust backpressure would be in the driver's log with a hole that small to pass air through, it was restricted down to 1". If you can't get the heat out, bad things happen fast with pump gas. Surprisingly though, it never cracked a ringland.

Interestingly enough, because the turbo has a .96 AR T4 housing, it would still spool, whereas, I have heard of guys realizing that they had a collapsed flex pipe because their turbo wouldn't spool but they were using S475/S480 setups with that 1.32AR T6 housing. I have since gotten rid of the flex section and don't plan on using one in any future setups.