What weight oil did GM use in a 91 C4?
02-13-2005, 03:14 AM
#2
Team Owner
yup, 5-30. I recommend either Mobil 1 or Valvoline Synpower.
As for the pressure, it varies. When cold, it should be upwards of 60psi. once warm, it will drop, and should be about 10-12lbs per 1000 rpm. If it is ever below 10lbs, at any time, there is a problem. This is added to the base pressure of about 20psi or so.
I think that's right...
As for the pressure, it varies. When cold, it should be upwards of 60psi. once warm, it will drop, and should be about 10-12lbs per 1000 rpm. If it is ever below 10lbs, at any time, there is a problem. This is added to the base pressure of about 20psi or so.
I think that's right...
02-13-2005, 11:22 AM
#4
Team Owner
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Anytime your foot is on the gas it needs to be over 50psi, full throttle around 60psi. Warm idle should be at 45ish, hot idle can drop into the 20s, cold idle should be around 50-60.
They came with 5w30 I believe, but you can use any weight you want. I would only run 5w in winter months, otherwise 10w30.
They came with 5w30 I believe, but you can use any weight you want. I would only run 5w in winter months, otherwise 10w30.
