Hey ya guys. I am currently in the process of having a 1966 chev 327 being rebuilt for my 56 chev 210 and was asked by my builder if I want it balanced. I have done a bit of googling but was wondering your thoughts on this? I can imagine a smoother engine will be a better engine and at $470 its probably worth it? Its a nice street engine. No huge hp but will have a mild cam. Want a good reliable streeter.
Thoughts?
moparpete,
Aug 2, 3:03pm
Get it balanced mate. Piece of mind with the engine in bits.
elect70,
Aug 2, 3:36pm
Yep any performance engine should be balanced also remove casting flash from rods& get them shot peened while hes at it .Be a nice little engine
mad_signtist,
Aug 2, 3:45pm
Cheers guys. I will look up shot peened haha
sr2,
Aug 2, 4:58pm
I'm going to put forward an alternative view and suggest that for a stock 327 street motor with a mild cam there is very little to be gained by balancing it. You won't notice any different in how smooth the motor runs and you should expect any well rebuilt SBC to be a very reliable street motor.
Don't get me wrong I've had many motors balanced in the past, but for a street application as described by the OP the money could be better spent elsewhere.
snoopy221,
Aug 2, 5:37pm
Heya Jason a note for ya okies. Use a damn good engine builder and make damn sure they put NEW cam bearings in the block and misalign the oil hole in the FRONT cam bearing The reason for this is as simple as. All big ends are pressure fed by a simple circuit which includes the main bearing AND the cam bearing. Therefore when building solid reliable engines one misaligns the oil gallery which increases oil pressure in the big end bearing when off loaded at high rpm's.
Also new cam and lifters and make damn sure first start up is with a good air ventilation system and EVERYTHING RIGHT and the engine is kept at half max rpm for a good twenty minutes so there is high oil pressure to slap the new cam and lifters in PROPERLY and enjoy.
patiki1,
Aug 2, 8:12pm
Are you using the same rods, pistons and crank?
extrayda,
Aug 2, 8:23pm
Just remember the forged pistons and to keep the compression lowish for when you slap the 471 on top. You know you want to.
supernova2,
Aug 2, 9:52pm
Misalign by how much? Not something I've ever done but I can see the logic.
bill-robinson,
Aug 3, 7:29am
personally I would not bother, just get it finished and enjoy it
the-lada-dude,
Aug 3, 8:09am
I agree with SR2 & Bill - R . waste of $ 's . & don't even think about using forged pistons ! . some of these engines have an external counterweight on the fly wheel or flex plate . don't mismatch that bit >>> these engines have a multitude of different cylinder head types . there are casting identification marks on the cyl head ends that tell what head type, the best of that era were what where known as Fuelie , or camel hump ( doubt if you will find any, and probably frigging expensive now ) I believe Vortec heads fit . I will tell you that you could pick up 30 % more grunt for $10 and 2 hrs work
Personally, with a full rebuild on an engine of that size, . AND I can afford the extra $500 for balancing, I would do it anyway. May well give you the edge on life span at higher rev's when you need it & should do it a bit easier.
sr2,
Aug 3, 6:27pm
On a street driven SBC there's no increase in life span from balancing, it will have no effect on how the motor wears.
extrayda,
Aug 3, 8:58pm
Forged Pistons was to go along with the 471 comment. not on a standard(ish) rebuild. Vortec heads would require a different intake (can't remember about the exhaust offhand).
tshop,
Aug 3, 9:10pm
If your changing slugs to lighter forged then yeap' a retailer will never tell one to remove the weight difference of the the stock piston to the new afm one, from the back end of the crank. Online you hear all this near enough chit chat about - or + balance but I know I still like my engines perfect just like a cars wheel 0000. An example of a perfectly balanced L4 to a - balance on e is the Hayabusa as opposed to a R1.
the-lada-dude,
Aug 4, 9:52am
I agree, a change in piston weight will change the bob weight calculation, but not by a lot. as the reciprocating mass is only 1/2 the weight of the basic calculation. then you must realize that a V8 has ROTATIONAL IMBALANCE in all three axis . no matter how you try to balance these forces one can only choose a compromise. therefore bob weight choice covers known limits by experimentation over years gone by, so unless you are trying to redeem some bad engine performance character, staying within those known limits will suffice, for in this case, I would call a LOW performance motor ,,,,There is STATIC and ROTATIONAL balance. poles apart
the-lada-dude,
Aug 4, 9:56am
I agree, a change in piston weight will change the bob weight calculation, but not by a lot. as the reciprocating mass is only 1/2 the weight of the basic calculation. then you must realize that a V8 has ROTATIONAL IMBALANCE in all three axis . no matter how you try to balance these forces one can only choose a compromise. therefore bob weight choice covers known limits by experimentation over years gone by, so unless you are trying to redeem some bad engine performance character, staying within those known limits will suffice, for in this case, I would call a LOW performance motor ,,,,There is STATIC and ROTATIONAL balance. poles apart I bet you wouldn't notice a weight difference of 100 gms ( cast V forged ) in performance or wear for this engine
ian86,
Aug 4, 10:39am
I've just been through this, not a small block chevy but a small 4 cyl in a car I'm restoring and planning to keep. I hummed and hard, its a waste of money etc, be ended up balancing it for piece of mind and the fact I'd cut no corners on the rebuild, and pleased I've done it now. Also surprised how much metal was removed from the pistons,rods,crank and flywheel. I know when someone puts their engine in to be reconditioned, balancing is not normally part of the process, but with older engines who knows whether the parts in it are the original, lots of parts may have been interchanged over the years . it is a 50/50 thing but if you are planning to keep it, it is probably not a lot of money in the scheme of things and you know its done .
the-lada-dude,
Aug 4, 11:15am
This subject is well related to older engines, esp old English inline 4 cyl 3 main bearing engines . in those early days dynamic crank and flywheel assembly didn't exist and static balance was left to the real enthusiast with accurate scales and knife edges . there is absolutely no reason this cannot still be done by any person today
tshop,
Aug 4, 5:46pm
Neh you can get em perfectly balanced/exactly is easy 0000. Its a sales ploy having something off or ugly It says "ImConfident" of the Product. To Suzuki engineers Hyundai & Toyota its just plain InCorrect".
bill-robinson,
Aug 5, 8:04am
as i said, build it and use it. it is a standard engine or, are you genius's telling me GM built millions of faulty engines.
the-lada-dude,
Aug 5, 11:40am
I will question your engine design ability . you will NEVER rid the engine of an inline, V or radial piston engines of a 1st order rotational moment in all three axis . you can balance the componentry to your f&*king hearts content to a millionth of a gram . the moment you start the blighter , the friggin thing will want to jump all over the place . ask your self why Norton developed the isolastic engine mount system for the last of the big twin m/c's, and there are plenty of engines using counterweight balance shafts. why ? . there is only one engine cyl configuration that eludes this 1st order imbalance .
the-lada-dude,
Aug 5, 11:52am
agree, i'd be spending time and a very small amount of money on flowing oil galleries, a 3 angle intake valve job, matching all the intake port faces, a substantial radius on any turns in the intake manifold esp under the carb and there is lots you can do to clean up the air flow into the carb
mrfxit,
Aug 5, 12:11pm
Still can't to at least a basic balance check of components. Now, . isn't like the old days where we could afford to build an engine every month because we didn't get it right 1st time or we were just plain stupidly in a hurry.
mrfxit,
Aug 5, 12:15pm
Most factorys build engines etc to fairly exacting std's with all components cross checked for quality at random & scheduled points. Those std's ensure that everything is within tolerance at every stage.
Thats not generally going to be the case with second hand parts from unknown engines that have had any number of previous rebuilds or harsh treatment over many years.
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