Reckless

iTrader: (9)

I have a new stock crank that has never been run, new Eagle rods, new Wiseco pistons, and was wondering if internal balancing is really necessary. Max RPM will be about 6500 and will use a little N20 along the way. What are your thoughts since the LS1 is already internally balanced?

C5kid

iTrader: (12)

if it was me i would do it just to be safe, it would probaly even yeild 2-4 hp just because things are spinning nice and even

99 Black Bird T/A

iTrader: (4)

I would, it always pays to double check other folks work. The rods and pistons etc might be dead on...then again maybe not. I'd balance it.

Fireball

iTrader: (21)

since your pistons/rods aren't stock weight (aftermarket) I'd definately have a full balance done

10.5 Dave

iTrader: (5)

Todd I'm shocked you even considered not doing it.I think it would be penny wise and pound foolish to skip this important step.Good to see you coming together.Dave

99 1LE SS

iTrader: (1)

If you were using stock rods and pistons id say no, but because you replaced the rods and pistons with aftermarket its a wise choice to because of the weight difference. Your bearings will thank you in about 20k miles also.

Assassin

iTrader: (3)

do those engine balanceing kits they sell in the magazine really work, or how is it done?

CHRISPY

Definitely get it balanced. No question about it.
Chris

Reckless

iTrader: (9)

OK guys...thanks for the inputs. Local machne shop said only about $150 since the LS1 is already an internally balanced setup. Should not be too painful I guess. Will prolly drop off the parts this week for balancing.

Vents

iTrader: (9)

good choice. i contemplated not doing mine, but in the long run, it's much nicer. im very glad i did it. makes things VERY smooth up past 6500. and there's no "man... now im gonna have to take this thing all the way back apart to have it balanced" feeling there either.

robertbartsch

Question:
If you bought a rotating assembly (Lunati) I assume it is balanced and ready to install; right?

Reckless

iTrader: (9)

I believe they are, but many have them checked any way. I have heard they are not always just right.

01TA

iTrader: (7)

FWIW I had talked to my local machine shop a while ago about possibly rebuilding my shortblock. When I said Eagle H-beams, he told me it would cost extra to balance. Because the Eagle rods are so much heavier than the stock LS1 rods, he would have to use a lot of mallory metal for counter weight.

Vents

iTrader: (9)

it think it depends on the machinist, but i didnt have any material added to mine, just removed.. diamond pistons, eagle h-beams, stock crank..

strokedls1

iTrader: (1)

If you have ever seen an unbalanced engine run you would gladly pay the $150. My balance work cost $650 so don't feel bad.

Pro Stock John

iTrader: (34)

You have to balance it since you have aftermarket rods and pistons.

blu00rdstr

I just had balancing done - Diamond pistons & pins, Eagle rods, stock LS1 crank, balancer, flexplate, rings, bearings.

The pistons were untouched as they were perfect. The rods had some of the piston end ground. The balancer wobbled, and I replaced that. The bearings, pins and rings were needed to set the bob weights. The crank was way off, see pics below:

robertbartsch

hey 98 roadster:
...so they found the lightest connecting rod in the bunch and removed material from all other rods to make them all the same weight, right?

Then the bobweight was determined and the crank was balanced to this weight, right?

About how much di this cost?

Reckless

iTrader: (9)

I dropped off some of the parts at lunch, but forgot the flex plate, rod bearings, and rings. I trust these guys because they have about 30 of those NHRA trophies from the last few years. They build big dollar Mopar stuff (hemis and such) and they also race a lot.

Those are some good pictures that show how minor some of this stuff can be, but how important it really is to making your engine run smoothly.

JimmyKash

balancing isn't important for hp but basically for harmonics....a horribly unbalanced crank can cause premature failures