So I've done my homework and so far I'm left with my theory that OEM parts are there for a reason, therefore Mitsu had a plan for the balance shafts - they are not there for show. With that aside, it is obvious that the design is problematic and can cause more hurt than good in one fell swoop. Here is what I want to know: Can't I just change the balance shaft belts and bearings every 60,000 miles with the timing belt? Basicly, the problematic design lies in the rotating speed of the balance shafts, right? Hence the low balance shaft bearing life-span and high heat created by this problem. Why can't we either A. Replace the bearings and balance shaft rotating parts every timing belt change or B. Engineer race/high quality bearings for the balance shafts elongating there life. Preferably we can perform A and B so we feel ultimately secure.

I also wonder if the problems people see with removing balance shafts are directly related to the way people are doing it. Some people claim immediate detrimental effects after the removal is performed and I can't help but wonder if somebody didn't line a belt or pulley up straight or did not torque something to specs. Possibly incorrect assembly or in the wrong order. Other than that people complain that the oil pressure is too high but we are not working with butter here, we have iron blocks and pretty strong internals- what kind of harm can high oil pressure cause? Does it have the same effect as an oil with higher viscosity by taking away precious lubrication?

I just purchased a 05' Evo VIII with 38K and it couldn't be in better shape. Lets put it this way the only thing my friend and I could find wrong with the car is a pee sized nick in the hood. I am about to buy the VIII ultimate service kit II from mitsubishiparts.com which has the Gates Kevlar belt set and water pump, etc. I want to ensure this engine lasts as long as possibly by maintaining it. My rule of thumb is to change the timing belt and associated parts in an interfering 0-clearance engine with a timing belt. The first problem I have is finding a reputable place and tech to do it in the Baltimore/Harford area but the second problem is finding the correct methods to keep this engine going since there are so many controversial topics. The reason I bring this up is because I do not know what to do! I want to remove something that may take out my timing belt (I've lost 2 engines to failed timing belts) but I never go against OEM grain and I would like to make a wise decision- so what should I do? I'm considering the Toga High Volume Oil pump for longevity of my engine but will this be a really bad decision with the removal of my balance shafts? High volume is different than high pressure, however. Does anyone make aftermarket balance shafts or balance shaft bearings? Please help I want this engine to last. Any other suggestions?

Thank you guys, this is the best EVO community. I am happy to be a part of it

 

Help, please. I need to keep this car running but I don't know the first thing about 4G63 maintenance. Does anyone know what the scheduled 60K service would be? I've been looking for a service manual to no avail..

 

what are your plans with the car? mods?

 

I am not sure about you plans for the car, but I doubt you would want to remove the balance shafts from a daily driver. The balance shaft problems that I am aware of relate to the removal of the balance shafts in a built motor. One balance shaft is driven by a dedicated belt and can easily be removed by sealing off the oil passage with a rotated bushing. The other balance shaft is the idler gear of the oil pump driven by the timing. A method to remove that shaft that was tried in the past was to cut the shaft at the exit of the pump housing. This causes a problem because that left only one bearing on the shaft which will wobble of destroy itself. The proper way to remove the balance shaft is to turn the counter weights down on a lathe until the shaft is round or purchase a machined balance shaft from AMS or similar. I am not aware of significant issues relating to stock or properly built balance shafts, but I could be wrong and there are many more experienced people here.

 

I originally planned to keep it stock until it blew..which would be followed up by a complete rebuild since the motor would be out at that point-but i've changed my mind. Figure 400whp max. My next mod would be either a bastard 20g or a real 20g. But in all seriousness before that i that next set of mods would be larger injectors, a walbro in-line, engine management, a dyno tune, and a boost controller. I have a profec e-01 but i might sell it seeing it may be ineffective now. I want power but not at the risk of longevity or reliability. Of course your going to see normal wear and tear with those pressures however i have always been the one to take the safe route by implementing stronger sleeves and internals, block guards/girdles, high performance bearings, and so forth. one thing no matter what i do will remain: its my daily driver

 

Put a stock motor back in it and slap a BBK on it. No need going for full build. Id part out whats your left of you old motor and just buy a used stock engine, much less headache and time.

 

First, there's nothing wring with Mitsubishi's design with the balance shafts. As long as someone with experience and paitence is doing your install, you'll be fine with them. I was making 435awhp for 12,000 miles with stock balance shafts.

The balance shafts become a problem when you start revving the motor to higher rpm (I.e. Above 7,800), or if you install them wrong. If you don't plan on revving high, and paying someone reputable to do the job, keep them.

If you do decide to delete them, it's an easy job while you're in there. Takes no time at all. Once you're in there and the timing belt is off, the actual process of "deleteing" the balance shaft takes less time then filling your car up with gas.

-James

 

The balance shafts are installed from the factory because an inline 4 cylinder is inherently unbalanced engine by design. Some Honda K series came with or without balance shafts in otherwise the same engine, just depending on application. What I am saying is balance shafts are more for annoyance vibrations than detrimental engine harmonics.

The problem with them lies with high rpm, The balance shafts spin at twice the speed of the crank. Stm was spinning their stock motor to 9k so you do the math. People remove them because it frees up rotational mass and there is now zero chance of the balance shaft belt taking out the timing belt. Another lil bonus is it makes timing the engine much easier.

Its bad when oil pressure is too high because then it adds unnecessary heat to the oil. Oh and as for you saying you are all for OEM the stub shaft that replaces the balance shaft in the oil is pump is a factory Mitsubishi part that cam on a 1.6l they offered that uses the same oil pump.

 

The balance shaft is only there to reduce vibration and make a "smoother" engine. No need to re-invent the wheel here. People have done well removing them and people have done well leaving them in. The problem is when they are not serviced correctly. It sounds like your car will be a mild setup so don't worry too much.

 

4g63 engine delete balance shaft kit whats the long term effect ?

 

True, if you are talking about the time it takes you to tell your mechanic to do it.

 

GSC makes a balance shaft replacement kit.

http://www.power-division.com/home.php?cat=292

 

If the stub shaft is good for an OEM where the motor has to last forever then it shouldn;t be a problem.

 

Agreed.