Balancing Rotating Assembly

[fleetwood472]

The machine shop by me quoted me $268 to balance my crank and rods is this price high? Also is this something I am going to need if the motor isnt going to turn over 5k rpms? Is it worth it to have this done? What do you guys think? Thanks - Justin

[CadilaChris]

I thought that Cady balanced them at the factory. Anyway, in terms of laber and time, that price isnt that bad. I think you would only need it balanced if the rpms were going to stay around 4-5 thou. For street use, it dosent help at all.

[abcdefg1675]

$268.00.. Hmm. Ive never had any work done, but it sounds fairly cheap to me.

Wouldnt it be wise to use stronger rods, then pay out the 300 for balancing? If you actually have done something to your engine, to where it will rev up good... I would go for it. But, are these people someone you can trust to do a good job? crank balancing sounds like a job that would require a trained professional, who are also highly paid.

[dave_brode]

472,

Sounds high, compared to 'round here. Runs $150 or so, plus $50 a slug for mallory, if needed.

Caddy engines are closer than most from factory, but they still benefit from balancing. They are not "balanced" from factory. You would see tool marks from the process. They *may* have weight matched the rods and pistons, but I've never heard proof of it.

Dave

[CadillacPat]

While it isn't necessary, ANY engine will run smoother if properly balanced. At a MINIMUM, mix and match pistons/rods/bearings/rings to at least balance the entire piston/rod/bearing/ring assemblys. The Silvolite pistons I recently bought from a seller on bay have an instruction sheet in the box that states the pistons are +/- 2.5 grams.

[Modly]

If you balance and line bore/hone, you will notice a difference. The engine will run with far less vibration, and last much longer.

For a balance job, that sounds like an alright price. I think it is about $50 less around here to have it done, but every shop is different. If they specialise in balancing though, you can be pretty safe and sure that they will do a good job, especially if they have been around a while.

Just remember, if you go the extra mile, you'll end up with a better engine. If you cheap out, and do the bare minimum, you'll get a poorly made engine.

[fleetwood472]

Do you get any extra hp from decking and squaring the block? I have heard that these blocks rarely even need to be decked and that cadillac won a manufacturing award on these motors. Supposedly the motors were far better machined also compared to most other production motors of their time. Does the caddy need to be align honed if you use arp main studs? Is it worth it just to have it done anyways to make sure everything is exact? What do you guys think - Justin

[CadillacPat]

Justin,
I believe I read about the Cad engines being machined a little better than most, but, that was "for the time". By today's standards, this is not the case. To save a little money, you could CHECK the block's square to see if in fact the engine is square. Then, if it is not, you could then have it squared (and therefore decked at the same time). However, since it is necessary in most cases to surface the block to get the desired deck height for proper quench, and, to get a clean surface for gasket sealing, by decking you would be accomplishing three things at once.
As far as line honing, it certainly can't hurt and at a minimum the crank would spin more easily which would result in a smoother running engine and less internal friction which would increase HP.