91 C1500 Ignition Timing
seabee-scum
11-11-2004, 10:36 AM
Is there anyone out there that knows the exact timing spec. For a 91 GMC C1500 2wd 5 speed M/T with a 5.7L. And i don't believe it's 0 degrees. I've set it to that and it doesn't run great. And yes i do know about setting base timing and disconnecting the EST. If i advance it to around 8 Btdc runs awesome just ALOT! of valve ping. I rebuilt my engine and after all was done i realized my emission label under the hood is missing, sucks to be me. Does anyone have the same make?? Thanks.
2000CAYukon
11-12-2004, 01:38 AM
I have a 90 K1500 5.7 Automatic. The emissions sticker says Automatic and does not show a timing spec for a manual. I also have all of the Factory Service Manuals and they all say to look at the emissions sticker. A local dealer should be able to tell you the timing. I usually ask the parts guy if they can ask one of the mechanics to look it up.
Also, since you know it runs better at 8 then 0, back it off 2 degrees and see if the pinging stops. Repeat until the pinging goes away.
Did you put a new cam in the engine? If so, did you degree the cam?
//2000CAYukon
Also, since you know it runs better at 8 then 0, back it off 2 degrees and see if the pinging stops. Repeat until the pinging goes away.
Did you put a new cam in the engine? If so, did you degree the cam?
//2000CAYukon
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