I had to back down to 7 psi from 9-10 with the same knocking problem, I'm running 10.3:1 compression, and TR-6s.
2000 Sierra 2500 HD. 408 (11-2007) Whipplecharged, Big (18x24x4) FMIC.
I don't think my compression is quite that high. Should be around 9.5:1. I bought my TR6's today and will give them a try. 8 psi was not issue for me but 10 seems to be the magic number. I'll post updates once I put them in.
2004 Silverado Crew Cab, forged iron 5.7, STS w/MP turbo, 10+ psi, FMIC, Tial 50mm BOV, Vic Jr, Snow performance meth, MTI Stealth cam .220/.220 .581/.581 115lsa, Comp chromoly pushrods, Yank TT3000 stall, LS1 Efans, 160 tstat, Trucool 40k trans cooler, 60# injectors, Walbro fuel pump, Patriot springs, Built 4l65E w/billet input & output shafts, Eaton posi, SD tuned...all installed by Klein North Automotive
2004 Silverado Crew Cab, forged iron 5.7, STS w/MP turbo, 10+ psi, FMIC, Tial 50mm BOV, Vic Jr, Snow performance meth, MTI Stealth cam .220/.220 .581/.581 115lsa, Comp chromoly pushrods, Yank TT3000 stall, LS1 Efans, 160 tstat, Trucool 40k trans cooler, 60# injectors, Walbro fuel pump, Patriot springs, Built 4l65E w/billet input & output shafts, Eaton posi, SD tuned...all installed by Klein North Automotive
So I put the TR6's in and still have the same problem. The old plugs look like they might have been running on the lean side. One had some orange on it not quite as bad as ff_jeff's but close. I'll take pics and post. Still don't understand why unless my PLX is not giving me a correct reading. AFR is still around 11 + or - and timing is 14-15 degrees. I adjusted my meth to come on sooner and still audible knock but not being deteced by scanner. Any ideas????
2004 Silverado Crew Cab, forged iron 5.7, STS w/MP turbo, 10+ psi, FMIC, Tial 50mm BOV, Vic Jr, Snow performance meth, MTI Stealth cam .220/.220 .581/.581 115lsa, Comp chromoly pushrods, Yank TT3000 stall, LS1 Efans, 160 tstat, Trucool 40k trans cooler, 60# injectors, Walbro fuel pump, Patriot springs, Built 4l65E w/billet input & output shafts, Eaton posi, SD tuned...all installed by Klein North Automotive
What are your IAT's?
Gone, but not forgotten!
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IAT's a running around 70-90 degrees depending upon ambient temps. Typically +5 to ambient air and -5 after WOT run.
2004 Silverado Crew Cab, forged iron 5.7, STS w/MP turbo, 10+ psi, FMIC, Tial 50mm BOV, Vic Jr, Snow performance meth, MTI Stealth cam .220/.220 .581/.581 115lsa, Comp chromoly pushrods, Yank TT3000 stall, LS1 Efans, 160 tstat, Trucool 40k trans cooler, 60# injectors, Walbro fuel pump, Patriot springs, Built 4l65E w/billet input & output shafts, Eaton posi, SD tuned...all installed by Klein North Automotive
Hmmm, fuel pressure @ WOT?
Gone, but not forgotten!
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