Front to rear balance line

Prepping for assy of the 455 and will be installing a balance line. Any reason 3/8 will not be ok?

 

3/8 is fine.however unless your only revving to 4800 if what is marked are your main clearance there too tight. .001 per inch of diameter is required. .003-.0032

 

Thank you for the input. Yes those are my clearances. It's what I requested. Rods are @.0022

 

The more oil you feed, the more oil have to get away. Too tight and you will burn your bearings.

 

If the mains on a BBC crank are 2.749 or there abouts, much smaller than Buicks 3.25, how can a Chevy get away with .003 or larger oil clearances if you used the .001 per main journal diameter clearance "standard"
Does it have to do with the journal diameter and bearing speed difference between the Chevy and Buick main diameters?
Im not disputing or arguing the issue, just want to understand

 

Man no one would build my buick that tight, or any motor that tight

I like the oil to getninnthete. Move through and live and cool......ill take a few psi drop on the gauge to know I have oil flow and a cushion to ride on

 

I’d rather have .004 than .002 in a performance application. Also Chevy has a cast-iron oil pump and Less restrictive oil passages. not a cast aluminum which holds its oil pressure at higher temperatures. Remember the old saying goes when it’s tight everybody knows, when it’s loose nobody knows.

 

3/8 line no problem.

 

According to posts by JW, 0.002-0.0025" on the mains is fine for a street engine.
And I suspect a balance tube isn't as necessary at the tighter clearances than it would be at 0.003"++ where you're flowing a lot of oil. It's good insurance tho!

 

Regarding my bearing clearances, my engine is mainly a street application and that's typically the recommended clearances for such an engine. I feel comfortable with those clearances. The balance line is just added insurance and I feel like I can hide it well enough that it won't be obvious to the casual onlooker.

 

Interesting opinion: "The bypass line is a "quick fix" you can apply to the engine with it still in the car to improve the driver side valvetrain oiling. You have to drop the transmission and remove the flywheel/flexplate to get at the rear oil passage plugs to do this, but it's cheap (about $15 for the kit) and it helps stave off a rebuild for a while longer on a stock engine. Note that this does not help with cam bearing oiling and should not be considered for any engine that is being rebuilt." and "The heavy-duty grooved cam bearings are the easiest and best solution if you are already doing a rebuild. Just install the new heavy-duty grooved cam bearings in the "preferred" positions as noted in the next section, and you're good to go. This improves both cam bearing oiling and the drivers side valvetrain oiling - and it requires no extra machine work."
from http://www.rowand.net/shop/tech/buickoilingimprovements.htm Seems to go against conventional wisdom.

 

I always thought the balancer line was to make sure #7,8 rods and mains get adequate oil because the bottom end got oiled last?

 

That's exactly what that balance line does. The other one sometimes called the bypass line simply ties the two oil passages on left and right together. I'm not doing that.

 

B
BTW, I run .002 and .002 on all street motors. May go .0023 and still .002 on rods. Don't go to .0025 and.0023 till race . Some say I'm too tight but it's been.very successful so I'm sticking to it. Run 10w40 no thicker.

 

From Joe(436'd Skylark): The rod bearings get their oil from the mains. The more that leaks out in the mains from loose clearances the less the rods get.
From Larry(The Wizard): There is a reason Buick built them with tight clearances. Larger clearances bleed oil pressure from front of the block to rear. #7 and #8 rod bearings are the last to get oil.
I should have said front to back, not bottom to top. Point is, you need tight clearances.
See - https://www.v8buick.com/index.php?threads/main-bearing-clearance.371576/

 

You’ll be fine at those clearances I’d think, your a fuzz looser than Buick spec’d but not so loose your worried about oil pressure being low, just don’t use 20/50 oil

 

I run .0022 to .0025....mains and rods in race engine. Stock Buick factory clearances are even tighter.... .0015-.0018.
If crank is straight you can go that tight IMO. Many have some runout....and then shops will run looser clearances.
Had one engine that was .0035....ran strong but not as long....had to run 20w-50 oil.

 

I run .0024 #1-4 and .0028 #5 on the mains, and .0023 on the rods for my Pure Stock engine and so far so good....

 

Yes sir,if you put a oil pressure gauge at the front and another at the rear you'll typically see a 12 psi drop. So if you have 60 psi at the front and think your good to 5500rpm at the back you're only 48, i've seen a lot of hurt motors at #7 &8 when the customer told me he had plenty of pressure.;