Mods are:
3.5" MPS, 180* T-Stat, ceramic coated PLOG, 3" ZZP Catless DP, 10.5mm ZZP wires, AL104s, K&N large cone intake, ZZP Alternator Rewire.
Using HP-Tuners, I am seeing consistent 11.0 AFR at WOT. Peaked at 9.6* of KR yesterday evening. WAYYYYY too much for my comfort. Any recommendations on what I can do or check??
Thanks in advance
Post the tune.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Are you seeing commanded 11.0 or actual 11.0 reporting from a wideband ? usually once you see what actual afr is on a wideband and then get fueling to where your actually in the 11's problems diminish .
Short of a wideband I would check fuel pressure with a guage on the Schrader valve of the fuel rail to see if your losing pressure due to bad pump , poor ground/voltage etc...
a 3.5 pulley with only a plog and dp for exhaust mods will likely still see some kr but shouldn't see that much unless fueling is way off or its boost stacking , your not getting 13/14 psi are you ?
PB's 1/4 mi 12.21 117.75 trap ,1/8 mi. 7.779 93.99trap , 1.949 short time (FWD W body)
He's peaking at ~10psi which seems like quite a bit with a 3.5"!
Why arent you logging your MAF Hz or AFR err %?
I am a total noob but maybe it's a fueling issue? No way you should be getting that much KR!
1999 Riviera L67 SII 3800
XP HOT cam, 140# springs, Gen V swapped, 60# inj, E85
Sorry for the delay guys. Thanks for the replies!
I do have a wideband and the ECU is commanding AFR = 11.0, and I am actually seeing 11.0-11.2 on the wideband so it is pretty much spot on. No fuel issues that I know of (injectors appear to have consistent PW and duty cycle, new fuel pump, runs just fine).
Boost at WOT stays consistently around 10+psi which is reasonable for a healthy motor with good compression on a 3.5" pulley I believe (stock pulley is 3.8" which gives 6-7psi. Figure about 1psi added for every 0.1" reduction in pulley size, so 10psi with a 3.5" pulley is about right).
You're right about the PSI, my bad.
Please post your high octane timing table or your actual tune. I am currently tuning with a 3.6" with what I think is high timing and close to 0 KR. I am curious to see what your tune looks like to get 9 degrees of KR.
I was recently tuning with a 3.4" with low timing to keep the KR down. Decided to try a 3.6" tune to see what results I can get. Wish I had a 3.5" to experiment with!
1999 Riviera L67 SII 3800
XP HOT cam, 140# springs, Gen V swapped, 60# inj, E85
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