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if worse comes to worse and i have to tear the bottom end down to replace a piston and/or crank rod, the motor is going to get blanaced and possibly blue printed. i'll also get the balancer shaft removed. any other tricks for the bottom ends while its in the shop?
 

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I think the trick is to find a place to do the balancing for you. I found a few shops that can balance the V8's but not the 3800 :(

Greg
 

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hey greg thats the boat I am in. I found some that said "sure" they'll give it a shot :eek: Would you send you motor there :confused: I don't think so. I think a vendor could do quite well for shipping balanced lower parts and letting people install them themselves.
 

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That would be a good idea. Sell a balanced rotating assembly with a core charge. mmmm. I can get the block hone done almost anywhere. The balancing is the very important part.

Greg
 

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I had my crank 50% balanced here in Wichita, Kansas for $200.00.

You will need the following parts your going to use:
crank
rods with bolts
balance shaft with bolt
pistons with pins and atlease 1 complete set of rings
flex plate with bolts

Once this is balanced, you can now remove your gear driven, horse power robbing, factory balance shaft thats located under your intake manifold, and plug the oil feel hol on the back side of the block for the balance shafts rear bearing, and your good to go.

The shop that did my crank is the best I have seen. They do EVERYTHING with balancing cranks. Not just cars, they had motor cycles, huge air compressor cranks in there. As well as small block, big block and V6 cranks. They do a lot more of the 4.3L V6 cranks than anything else.

Yes people mail them their stuff, and they do the work and send it back out.

If your interested in this shop, let me know. I will give you the contact info.

~Farnsworth~
 

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I was able to get my bottom end balanced too. Cost me about $180 total. My crank was 60 grams off from one side to the other. They had to drill out a lot of my crank, the guy who did it assured me my motor will run smoother than ever even with a lopey cam.
 

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Hey guys, sorry for the ignorant questions, but I'm fairly new to the modding world and was wondering if anyone would be willing to tell me the advantages and process of balancing an engine, also, what does it mean to blueprint an engine?
 

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Balancing an engine is basically stated getting all the weights to match. In the case of some parts, such as pistons and rods, you want them all to weigh the same. Since inertia plays such a big role in standard 4 stroke engines (b/c the piston has to speed up, slow down, stop, then do the same thing in reverse) more mass on one piston means it takes more energy to stop it or get it moving (say from combustion). The factory can't get everything dead on from the factory, its unrealistic to have machines and people have to sit there and tediously make sure each is perfect, instead they have tolerances, say a part weighs 50 grams, they might say its okay for this part to be +- 2.5, so one part may weigh 52.5 g or even 47.5 g and still be considered acceptable. With rotating masses like the crank, you want it balanced similar to a tire. If your tire is out of balance, the car shakes, however a the more a crank is out of balance the more catastrophic it could be, especially when you consider all the weight slinging around and the speed at which its all moving. The crank is balanced by drilling into the counterweights, and adding "heavy metal" plugs w/ a higher density than the crank itself. By balancing everything to a tighter spec (say +- 1 gram which is normal in balancing), you allow the engine to rev higher (assuming your valvetrain can handle it w/o float), run smoother, and last longer by being easier on the bearings. Balancing requires an accurate scale (usally +-1 gram accuracy or +-.1 gram on the expensive ones) for the reciprocating parts, a special machine (like a tire balancer) for the rotating assembly, and skill in knowing where it is acceptable to remove material and how much to drill the crank- this being said it is basically a job left only to a machine shop.

Blueprinting is similar to balancing, however it deals with distance measurments instead of weights. Again, all of the measurements (be it length of a connecting rod, diameter of an oil feed hole, cylinder to manifold port alignment etc) are given wide tolerances from the manufacturer to be cost effective. While they work fine for a stock engine, you really want more control over them for higher hp or higher reving conditions. Also, you can opt to control these tolerances to the loose end or the tight end or anywhere in between, one good example being cylinder-piston clearance. If you run a piston that'll expand a lot, you need to have the cylinders machined to the loose end, so you don't run out of room. Same for connecting rods, if you have rods that expand a lot once the engine is heated, you have to watch how much you mill off the heads and block (as well as cam timing) to make sure a piston doesn't contact a valve. Blueprinting requires many measuring tools, such as calipers, micrometers (inside and outside), and so on, as well as a way to actually correct tolerances how you want them (this is where the machine shop comes in). While you can do the measuring yourself if you have the proper tools, it takes a pretty good understanding of whats going on, as well as what your options are at the machine shop to be able get everything done properly-basically a job only for one who is very experienced. Hope that helped clear it up a little.
 
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