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Re: Can someone educate me about ignition timing reading
If you are in high gear and rpm's are below 2500 rpm timing should be around 28-33 degrees on flat ground. When you go up a long hill that is steep enough to get you over 5 psi of boost timing will drop to around 13 degrees. If you hold it there and it begins to knock you can watch timing drop. If it gets below about 10 degrees it will start "rich knocking" because it doesn't have enough timing to burn all the fuel going in. This can cause timing to cascade down into the single digits. If timing is in the single digits it will have very little power. I'd say single digits are when you know you have a timing problem.
If you see timing in the single digits you probably need to desensitize the knock sensor more. I mounted my GM knock sensor at the lower rear of the block near the oil pan to make it pick up less engine noise so it would run more timing. It seemed to work fine like that. It still picked up big knocks but it quit reducing my timing on cold mornings when my old worn pistons were slapping. I watched my timing drop to zero on level ground cruising on the highway once on a cold morning. That's when I decided something had to be done to desensitize the knock sensor. I did the GM knock sensor mod and mounted it where I described. It really helped restore power at low rpms. Your forged pistons will probably slap a lot until they warm up and expand.
'02 Single Cab 4x4 3rz-fe. Holset he351cw Turbo. Treadstone manifold. Megasquirt. Four additional 200cc injectors. Vortech inline fuel pump. Bar and plate intercooler. Flex fuel. R150F trans swap. 354whp 376wtq at 15psi on E85.