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Are there noticeable differences between an 4 bt engine that have been balance and another one that have not been balance.....
 

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I don't think anyone here has had theirs balanced yet. Lots of talking about it, but I don't think anyone has done it.
 

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My Isuzu 4BD1T was balanced a while ago. Made a huge difference but the bigends were 17g apart in weight.

Blueprinting, why bother?:grinpimp:
 

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balanced

Mines balanced but not running yet hopefully in the next few weeks (but I've been saying that for awhile now)
 

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September issue of Diesel Power mag,Chaz Lightener 4BT in a old Bronco.Balanced and blueprinted 400 HP.Great article and the reason I found this web site.Great place with lots of information.
 

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Forgot to mention the article stated Beck Racing engines in Phoenix built the engine and Turbo Auto Diesel handled the pump and the rest of the power.
 

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Just my 2 cents, but cost shouldn't be the 1st question. In the entire top half of California including Sacramento and the Bay Area there's one and only one shop that I would take parts to for delicate balancing. You want the whole reciprocating assembled balanced, crank, rods and pistons. Find a shop that's well respected with local drag racers and go from there. Figure on maybe a couple of hundred $ for quality work.
 

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I have a machine shop that builds modified race car motors and they have someone they send all there cranks to get balanced. I am assuming if they do something like that a 4 cylinder that cranks outs a mere 3500 rpm or so should be something they can accomplish. My friends uncle owns the machine shop and he is a racer, so I get alot of feedback from him. What do you think?
 

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I had the rotating assembly in my Olds 455 balanced for $150.
 

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Just my 2 cents, but cost shouldn't be the 1st question. In the entire top half of California including Sacramento and the Bay Area there's one and only one shop that I would take parts to for delicate balancing. You want the whole reciprocating assembled balanced, crank, rods and pistons. Find a shop that's well respected with local drag racers and go from there. Figure on maybe a couple of hundred $ for quality work.
You'll want to take in your crank pulley, flywheel and clutch pressure plate too. All rotating parts with a huge influence on rotating balance.
 

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Thats very good to know. I was wondering about the flywheel, that thing weighs in at about 60lbs. A rotating mass like that off balance just a little bit I think would cause some nasty vibrations.
 

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Discussion Starter #14
I have a machine shop that builds modified race car motors and they have someone they send all there cranks to get balanced. I am assuming if they do something like that a 4 cylinder that cranks outs a mere 3500 rpm or so should be something they can accomplish. My friends uncle owns the machine shop and he is a racer, so I get alot of feedback from him. What do you think?
Correct me if I am wrong...I am new to Diesel and I am trying to repower a ford 1995 with a 4bta, must be reliable with 30 mpg/175/200 hp I was reading that cummins cut down vibration 30 %on their new ISB engines by balancing the crankshaft, so by balancing a 4bta crank could reduce engine vibration hence noise ? :confused:
 

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Correct me if I am wrong...I am new to Diesel and I am trying to repower a ford 1995 with a 4bta, must be reliable with 30 mpg/175/200 hp I was reading that cummins cut down vibration 30 %on their new ISB engines by balancing the crankshaft, so by balancing a 4bta crank could reduce engine vibration hence noise ? :confused:
As stated above - you must balance the whole rotating assembly, just doing one component of the system will not do it.
 

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You'll want to take in your crank pulley, flywheel and clutch pressure plate too.

No....you don't want to include a part in the balancing that may need replacement later.

The front pulley doesn't have enough mass to really affect anything. The pressure plate is NEVER included in the balance.

The flywheel could go either way.... in race engines it is a part that can get changed frequently so it is never included in the balance of the assembly.
 

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Yeah, normally it's better to balance the flywheel and balance the reciprocating assembly separately. Otherwise you have to rebalance the whole engine or lose the balance job if you should have to swap flywheels, not uncommon with built diesels. In order of preference I'd say it's rods, then pistons, then crank rotating assembly.
 

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No....you don't want to include a part in the balancing that may need replacement later.

The front pulley doesn't have enough mass to really affect anything. The pressure plate is NEVER included in the balance.

The flywheel could go either way.... in race engines it is a part that can get changed frequently so it is never included in the balance of the assembly.
If everything is individually balanced, then it doesn't matter at all what parts you include and what parts you don't. Even if those parts are replaced later.

My pressure plate has been balanced and they took a fair bit off it in the process.

Trying to balance a crank and not the flywheel is a mark of insanity.
 

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Trying to balance a crank and not the flywheel is a mark of insanity.
That is why the flywheel is normally balanced separately.

Marrying a particular flywheel to a rotating assembly is insanity.
 
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