Balancing a Honda crank worth it?

[myk]

Is it worth my money to balance a Honda crank? Looking into it I found that there already balanced almost perfectly from the factory. Why I'm asking cause I was planning on putting my f22 crank and rods into my H block. Now I plan on using this car as a DD but money is tight and I know some places charge upwards of 400-500 just to balance/knife edge/micropolish a crank. Honestly if the thing stays balanced and reliable while its in there I really dont care for all that other stuff, ya I might not be maximizing the efficiency but all I'm looking for is gains over stock. The crank does have 150,xxx miles on it, Im guessing the mileage might play a factor in how balanced and how much wear is on the crank.

Im really torn between sticking in this crank and rods or just slapping a rebuilt head on and tuning it as is with my bolt ons to see what I get... Maybe just some stage 1 cams and tune would be a better/safer choice.

-EDIT-My goal is to break 200whp this year, money has become pretty damn tight. I have all good quality bolt-ons, including a good header and Euro-r IM (matched TB). I only want to spend, with tuning 700 dollars (Not including the price of assembling the head/mild port polish/3 angle Valve job)

[ChIoVnIdCa]

Just looking at it as gain to cost. Not worth it.

[ZeRoCooLCB7R]

Im swapping in my f22 crank as soon as i pass some other inspections.Looking for a lil more torque hopefully.
More tq = More HP?

[C91BLX7]

Most Honda cranks are balanced enough already.

[bruno8747]

If you are going to be using the F22a crank get everything balanced again. The f22a crank is not balanced to the specs as the h22 crank because it was never ment to rev that high to begin with.

[wed3k]

there's a tolerance when it comes from the factory and that tolerance can be large or very minor. i wouldnt risk it especially since 4 cylinders have a natural harmonic to it. having a perfectly balanced crank will make the motor more smoothly.

don forget your harmonic balancer, flywheel and pressure plate. id balance everything together. my boss balances eveery crank to perfect or 1-2 grams at 1 inch radius.

[myk]

The plan was to remove the balancers. If everything is balanced in spec what is the point?


More I think about it, the more it seems like it wouldnt be worth it to put unbalanced crank/rods into a DD motor. Like wed3k said you dont now what those factory tolerances were.

[benjerman112]

Is it worth my money to balance a Honda crank? Looking into it I found that there already balanced almost perfectly from the factory. Why I'm asking cause I was planning on putting my f22 crank and rods into my H block. Now I plan on using this car as a DD but money is tight and I know some places charge upwards of 400-500 just to balance/knife edge/micropolish a crank. Honestly if the thing stays balanced and reliable while its in there I really dont care for all that other stuff, ya I might not be maximizing the efficiency but all I'm looking for is gains over stock. The crank does have 150,xxx miles on it, Im guessing the mileage might play a factor in how balanced and how much wear is on the crank.

Im really torn between sticking in this crank and rods or just slapping a rebuilt head on and tuning it as is with my bolt ons to see what I get... Maybe just some stage 1 cams and tune would be a better/safer choice.

-EDIT-My goal is to break 200whp this year, money has become pretty damn tight. I have all good quality bolt-ons, including a good header and Euro-r IM (matched TB). I only want to spend, with tuning 700 dollars (Not including the price of assembling the head/mild port polish/3 angle Valve job)

Sounds good bro, lets us know what happens when us ?done. what about just knife edging a crank?

[owequitit]

The plan was to remove the balancers. If everything is balanced in spec what is the point?


More I think about it, the more it seems like it wouldnt be worth it to put unbalanced crank/rods into a DD motor. Like wed3k said you dont now what those factory tolerances were.

Like most things, the bottom end works as a system. Since the flywheel and crank pulley are part of the system, they absolutely have an effect on the finished balance.

Spending money to balance the crank but not the whole rotating assembly is kind of like putting on a latex glove to go skinny dipping. It doesn't make a whole lot of sense.

[Vtechno]

http://www.honda-tech.com/zerothread?id=2140214

[Vtechno]

Like most things, the bottom end works as a system. Since the flywheel and crank pulley are part of the system, they absolutely have an effect on the finished balance.

Spending money to balance the crank but not the whole rotating assembly is kind of like putting on a latex glove to go skinny dipping. It doesn't make a whole lot of sense.

[myk]

The original plan was to get the whole bottom end blueprinted and balanced. I don't think that is going to be an option anymore. I'm not one to half ass stuff I was just wondering if it be alright to only do the crank and rods, I kind of guessed that the answer would be no. I just wanted to verify.

I like the skinny dipping analogy with the latex glove lol.

[HondaFan81]

The original plan was to get the whole bottom end blueprinted and balanced. I don't think that is going to be an option anymore. I'm not one to half ass stuff I was just wondering if it be alright to only do the crank and rods, I kind of guessed that the answer would be no. I just wanted to verify.

I like the skinny dipping analogy with the latex glove lol.

So basically keep whatever motor you're doing stock in terms of bottom end, based on your situation.

[wed3k]

balancing is only about 175 bucks from the machine shop :shrugs:

[johnl]

The plan was to remove the balancers. If everything is balanced in spec what is the point?

The point is that primary balance and secondary balance are not the same thing, and 'knife edging' (or any other means to check the balance of the rotating and / or reciprocating components) has zero affect on secondary imbalances that are inherant in all engines (other than straight six and V12, which both have zero secondary imbalance).

If you delete the balance shafts you may well 'liberate' a small amount of power, but you'll experience (a lot?) more vibration no matter how well the crank etc are balanced. The balance shafts are actually 'out of balance' shafts that deliberately reate a vibration(s) that 'vibrate' in the opposite resonance to the secondary imbalances that are inherant in all inline four cylinder engines.

The secondary imbalances always exist no matter how good the primary balance of the crank etc may be (i.e. static balance as 'measured' when 'knife edging' the rotating components), and not the secondary imbalances that occur as a result of the rotation of the rotating components and the order in which the cylinders fire. All engines (other than straight six and V12) have secondary imbalances that cause vibrations, and no amount of 'balancing' of the crank / flywheel etc can eliminate them, or even make them less severe.

Straight fours are I think the worst in this respect, and the larger the engine capacity the worse the secondary vibrations tend to be, which is why straight fours rarely exceeded 2 litres capacity prior to Mitsubishi inventing the counter rotating balance shaft, which is typically used on any straight four engine larger than 2 litres (under licence to Mitsubishi).

Note that the balance shafts don't eliminate the secondary imbalances or resulting vibrations in the primary rotating engine components, but deliberately create other imbalances that create counter-acting vibrations tha 'cover up' the original vibrations caused by the secondary imbalances. The purpose of the balance shafts has only to do with NVH issues.

More I think about it, the more it seems like it wouldnt be worth it to put unbalanced crank/rods into a DD motor. Like wed3k said you dont now what those factory tolerances were.

The stock Honda components are I think going to be pretty good as far as primary balance is concerned. I can't see a worthwhile cost / benefit ratio in having it all balanced to even finer tolerances unless you're intending to rev your engine well over it's stock redline, but having it done can't hurt if you have the money to spend...