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davelee
08-07-2010, 06:19 AM
Hi,
I just built a new big BBC 622, and it is in a street car. The block was cross hatched honed with 400 grit. The motor is a 4 3/4 stroke with 6.700 inch rod. I am running total seal gapless top ring. The rings are 1/16, 1/16, 3/16. After I broke the engine in I put in valvoline racing oil 20/50 . I have a couple 100 miles on the motor and it seems like it burns maybe 1/2 qt per 30 to 40 gallons of gas. This is my first big inch motor. Is this normal for a motor this size? or did I over look something?
Thanks

kwkracing
08-07-2010, 06:45 AM
probably not. If it was built as a race engine it has a few extra thousands on some things and probably has no exhaust valve seals. Which is not a bad thing.

davelee
08-07-2010, 10:53 AM
It has New teflon valve seals on the intake and exhaust valves
thanks

chevy582r10
08-07-2010, 05:41 PM
Hi,
I just built a new big BBC 622, and it is in a street car. The block was cross hatched honed with 400 grit. The motor is a 4 3/4 stroke with 6.700 inch rod. I am running total seal gapless top ring. The rings are 1/16, 1/16, 3/16. After I broke the engine in I put in valvoline racing oil 20/50 . I have a couple 100 miles on the motor and it seems like it burns maybe 1/2 qt per 30 to 40 gallons of gas. This is my first big inch motor. Is this normal for a motor this size? or did I over look something?
Thanks

I built a 400 with 6 inch rods once. The wrist pin was way up in the oil ring. That thing burned oil big time with 20w50 in it. Maybe a quart every 150 miles or so. Changed the oil to 10w30 racing oil and could get about 2K miles to a quart. I figure the rings just couldn't control the heavier oil as easily. I never got to find out exactly why. I've built a bunch of other engines similar to this with no problem since then.

oldandtired
08-10-2010, 11:05 AM
Do you have the low tension oil ring package?

TheRabbit
08-10-2010, 12:50 PM
Do you have the low tension oil ring package?

X2.
And I wouldn't run 20/50. The thicker oil with low tension rings will make it burn oil worse. I used 10/30.