was wondering if i should have the 355 balanced or not let me know what you guys think about having a motor balanced !!!!
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was wondering if i should have the 355 balanced or not let me know what you guys think about having a motor balanced !!!!
I wouldn't spend the money for a quality build without having it balanced. If nothing else it improves long term life and reliability.
X2! If it's out / apart, it's worth the money & effort!
Runs smoother and last longer.
I can't imagine spending the bucks for a bore, new pistons and rings and maybe a set of rebuilt rods, possibly a crank grind etc without a few more $$ for a balance.
The last Ford 351W I built had some real interesting machining marks after it was balanced - more so then any other that I had had done by this guy so can only imagine how rough it would have been had it not been done.
Balancing is an essential part of engine building. If an engine builder tells you it is not necessary, walk away and find a reputable builder.
Thanks for the question and for the answers as I will put my hand up and admit I wasn't sure of the advantages.
stock engines are far from close ??? what is close??? this is what you should ask when spending money for a balance job. how are the hell you going to check it? as many on line shops sell.. GREAT DEAL Kits.. there mass balanced using not the real parts for weight . but number of what it could be as it.s a averaged out could be off as much as 10 grams or more a end . on stock stuff that ran other then new pistons . many guys balance the rods and pistons match stuff up this is the least i do if the guy will not spend the money for a full balance job. its not always the machine shop. if i have a machine i am paying for taking up space in my shop. i like to get paid to use it . but some guys are cheap . all new parts and big stroke cranks can get very intense$$$$ with cutting down counter weight to plugging heavy metal in the crank . so whats is close for me it is under 1 gram per end of the crank
how much does a balance job run for the motor
you will have to talk to the machine shop you use locally as there no set price state to state . my price to do a balance job may not reflect what the cost is locally for youQuote:
Originally Posted by Southernboss84
If I'm not balanced ....... I fall down. Just Sayin' **)
The last one I had done was $165 - and he b!@#$ed loudly as he quoted me firm price and it was a lot more then expected regardless of the fact that he had everything in hand first.
Pat's response is what you need for an answer - it varies by area
Hmmmm:HMMM: so your telling us now your not well Balanced ....:whacked:Quote:
Originally Posted by pro70z28
http://www.clubhotrod.com/photopost/...s/000_0895.JPG http://www.clubhotrod.com/photopost/...s/000_1412.JPGthat not bad ...really on price . i not going to post how much i get for a job but it,s abit north of that. some jobs can be a real pain in the ass if it .s been pluged up and welded you have to cap stuff off and make sure your not opening up someones plugs .can be a real can of worms . some of the great deal cranks do not have counter weight were it needs to be alot of drilling or truning the counter weight in a lathe or need more weight. heavy metal$$$. bad thing is some race cranks are starting to come this way with a very lite counter weight .so at this point we start to drill ream for a press fit plug of heavy metal like thisQuote:
Originally Posted by IC2
Your not the first one to mention that. If I eat right though & in moderation I never fall down, but sometimes I learn toward junk food.Quote:
Originally Posted by pat mccarthy
sorry :( my down fall is soda popQuote:
Originally Posted by pro70z28
Smokey Yunick in his book Power Secrets- "Frankly, I think engine balancing is anything but an exact science, and you don't need to get upset if things are off a little.
There's no such thing as an engine that is perfectly balanced at all engine speeds. You can determine a recommended balance weight according to the formula that the crank manufactures use, and pick a crank speed-say 5000rpm- to put in the formula with a different crank speed-say 7500rpm- the recommended weight will be different. So, at best you can only gain a "true" balance within a very narrow crank-speed range.
And from what I've seen, this true balance is at best a approximation. When you look inside the oil pan as the engine is running at high rpm, there is a tremendous amount of oil caught up in the windage from the spinning crank and wrapped around the crank throws. This oil has a lot of weight, and as the engine runs, this oil will migrate all over the assembly. Sometimes it hangs around the front throws, someetimes it is in the middle. The pattern is totally random and the size of the oil cloud can get larger or smaller. All of this happens in a test engine sitting on a dyno, so who knows what it's like when the engine is in a moving car and you have all sorts of front, rear and side loads in the picture.
This oil cloud must affect the balance of the operating assembly- and there is no way to account for it- so I little reason to worry much about engine balance. If you have to replace the pistons in an otherwise intact assembly or you have to do some machining or grinding- as is occasionally the case when you change a cam and a little more piston-to-valve clearance- I don't think you have to go to the trouble to rebalance the assembly if you can get the weight on the piston end of the rod within about two grams of the original balance weight. If you can get the replacement weight slightly less then the original balance weight, I'm sure you won't have any trouble. However, if things get out of hand-more than about three grams difference- you should get the assembly rebalanced to be on the safe side.
Wheelkid,
First, though you did not mention being new here, welcome to CHR. We look forward to hearing about your projects and seeing what you're working on as time goes by.
On balancing, it sounds to me like you're focused on the balancing of the reciprocating weight - the pistons, pins & rings, but not really considering the rotating weight and the dynamic balance. From my limited knowledge on the subject, the basic balance is three pieces - the reciprocating weight; the rotating weight or "bob weight"; and the oil weight, assumed to be 4 grams. Here's a link to a Ford Muscle overview that I found quite helpful in understanding the process - Engine Balancing and Crankshaft Balancing - FordMuscle
After the engine is balanced the flywheel, clutch & pressure plate are generally balanced, too, so that the entire assembly is considered. Once that process is complete, if you have to modify things later then you are working from a balanced starting point, and it's generally not necessary to re-balance the entire assembly - you can simply work from the base numbers, and modify your replacement parts to match, like changing out a piston you can match the weight of the one removed, as close as possible. No one is going to argue with you about the distribution of oil being less than perfect, but it's the starting point that's important. If you have a few grams of oil moving around would you rather it be from a very closely balanced base, or is it OK to have it being added to an imbalance of ten, twenty, fifty or more grams that's causing the crank to flex? I'd rather start from a solid dynamically balanced base, giving a much smoother engine. Others who have more experience in this arena may shoot me down on this, which is fine. I love to increase my understanding of these processes!!
Reading the above regarding Smokey.
1. Smokey's time was in the 60's /70's, equipment has come a long way since then;
2. Smokey mentions weights in grams. How would you know the weights? Unless it was disassembled and each part of the rotating assembly weighed!
In Smokey's defense of the above, he's already done the heavy lift and is now discussing maintaining a given balance. (IMHO)
In regards to the balance variable shifting in the rpm range. This is called harmonics and is a college course study in itself! Notwithstanding this fact, it is still far better to make every attempt to cancel out any vibration(s) for added longevity / reiability.
Seems Roger types more words... but alot faster!! :LOL: :LOL: :LOL:
Mike, my thought was that you said much the same thing much more efficiently!!:LOL::LOL::LOL:Quote:
Originally Posted by 34_40
OIL ? this is abit of a joke with some of my freinds we know were the oil is THE OIL PAN ? just not were it.s at 8000 grand :whacked: and harmonic s first post on this site i realy pist some guy who is not on hear any more about harmonics frequencys I was not going to go there in a small post and what happens in a oil pan or cylinder bores . rods big ends piston pins. push rods can flex go out of round ,aluminum heads were is the seat when the heads hot ? all things about can move from power . heat . distortion and at times harmonics . from were bolts are when tighten up some things we do things to insure stuff stays round when you bore or hone a block but we can not use the real heads . we can not bore and hone the engine under load but many do the best we can do . some way better then others smokey was one but he was off abit off on the 10 pound rule . same with the crank we do know oil ropes the crank we try to stop this . but at the end of the day you do the best you can and get the mass balanced. it will affect the engine very low speed if off alot. at the end of the day with all new parts we try to get them very close add for some oil on parts. pistons are alumiunum takes alot to throw a crank off for a fly cut for valves after going to a bigger cam .pistons they all are going to be even with same weight . as they were balanced before you cut them?? better to have a crank heavy then to lite so pistons you can go less gram piston all in match sets .but not one or 3 pistons heavy there ways to make things work if you get in to a engine that lost one or 3 pistons should buy a new set but it happens were the new pistons will not be the same weight piston pins can use a heavy or thin wall pin .pin end of the rods can be re worked . every part of a engine and action in it self is a science. the way we machine a engine is a science . the more you know the less you know about whats really going on. many know nothing
Charlie, you upset someone?? Nah.. don't believe it!! ;):rolleyes: :rolleyes: :LOL:Quote:
Originally Posted by pat mccarthy
And sometimes.. ignorance is bliss! HAH!! **):LOL:;)
So--------------while you guys been talking on the web about it---I've balanced 3 engines plus going out of town for 3 days--------
but-----------keep in mind that the oil going arond with the crank is ain a fluid condition,and will not affect the balance of the mass of solid materials
OH and i have not ???:rolleyes: your not the only guy on here that like hitting his head on the wall Jerry :whacked:..oil hanging in the wrist pins .. oil can fill drill holes in the crank and gets thrown out ?. oil is still weight i know were splitting hairsQuote:
Originally Posted by jerry clayton
charlie ? mccarthy Thanks you knew my greatgrand dad from Cork Ireland. or are you saying i am wooden dummy with someones hand up my back side ?Quote:
Originally Posted by 34_40
no go joe... let me think it a post saying oil has no weight :3dSMILE: ok its workingQuote:
Originally Posted by jerry clayton
Don't ask me any questions--I didn't read them--I was looking for something else and decided to try and copy/paste something------
Is all the snow melted over there yet????
Is this new guy from Michigan??? there is also a recent new guy posting similar Smokey stuff at Club Cobra however under different name/location (Mo) could be mis typed
Thought the same thing, Jerry. Monett, Mo is down in the SW corner out east of Neosho a bit...Quote:
Originally Posted by jerry clayton
Forgive me Pat.. I musta had Charlie on the brain.. 8-)Quote:
Originally Posted by pat mccarthy
Now I feel like the wooden dummy!
Maybe this is that 0W-20 oil with no mass, Pat?? Kind of like Coke Zero, no calories, no caffine, nothing there but wet and a taste!! F'n MAGIC!!!Quote:
Originally Posted by pat mccarthy
Jus' kiddin', Jerry, Jus' kiddin'!!
The oil in the crank passages I disregard except fot the Ford FE nascar cranks--------
I consider it part of the crank weight and since I can't prove that its uneven, I just regard it as crank weight-----
On the subject of the oil rope ing around the crank as it runs---doesn't happen--altho it appears to, it is an optical illusion that your eye and brain can't pick up--just appears like a blurrr--Now some oil appears to be going around with the crank, but it is really just being flong (flung) off centrifugly and in a picture (or real time) looks like its traveling with the crank, but as it comes off the circular rod throw as it revolves around the main axis, plus oil from the main will look like its traveling with the crank---
There is a HP differance on engines wit/without windage trays, scrapers,etc---which proves that the crank is turning thru that cloud of oil instead of it just rotating with the crank----
what the hell jerry ?i not much north then you are ?? . snow man it .s been in the mid 90.s shop is sweating all my machines tables and ways are rusting and i am not happyQuote:
Originally Posted by jerry clayton
Been doin' some chassis dyno stuff--at least they have some big fans---
here the damn parts washer makes heat, humitity faster than a/c can offset it--
weather correction factor for the dyno numbers is pretty wide--------
when i am short blocking engine no fan s are on .i do do care how hot it gets .i keep engines covered up when not working on them . no air :( shop celling is to hi i would go broke fast try to put air in the shop but it,s not to bad . yep when the jet washer is on. it.s wet i can power slide from one end of the shop to the other . i been thinking of buying one of them 4 foot fans you can get at tractor supply help dry up the placeQuote:
Originally Posted by jerry clayton
John Deere Green, Massey Fergiston red, IHC/Case???/
Yep --no doors open , no stirring the air----
yep when i build a hi rent engine i will not eat mexican the night before ...you do not have a tractor supply . you know china tools . china stuff . nuts bolts . paint .oil . babby chicks . feed . vet stuff for animals???? alot of candy and soda pop coolers by the check out ? and the dog bones they try to sell you before you get out the door ?Quote:
Originally Posted by jerry clayton
when I was real young---Tractor Supply was the speed shop for tractors----pistons / sleeves +.125----also discovered that pistons for propane engines was higher compression and used a lot of them---plus started using later model cranks in earlier tractors to gain 1/2 stroke