For those that have eliminated balance shafts.....

[Morphius]

When I swapped a 4G63T into my GGSX, I took the opportunity to liberate the balance shafts from the block. Soley because I intend to beat on the car and it'll be my winter driver, so I don't want to have to take it apart in the middle of the winter should the something go bad.

Long story short, it vibrates ALOT!!! I would compare it to when you get the balance shafts out of time. Does anyone else have this issue? The motor when you wind it above 4K is just loud. Louder than the 2.5 Bushur Turbo-back with a Magaflow muffler! I'm half scared to really wind her out. Cripes, had I know it would sound like this I would have never taken the balance shafts out. I know the motor wasn't this loud with the balance shafts.

Anyone else had any abnormal experience with balance shaft removal?

 

[kevingst]

Nope, nothing like that. My vibes only increased slightly.

 

[DevilSperm]

you did something wrong, i barely noticed a difference...you sure everything is timed right?

 

[TurboGraphX]

I have done SEVERAL balance shaft eliminations on the 4G63. Both turbo and non turbo.
You should only see a slight change in vibration if any. Most owners don't see any at all after my.
I would think that you have the oil pump spocket out of time, or you failed to fully tighten something.
you may also see a drastic increase in vibration if your front (radiator side) and rear (firewall side) motor mounts are already warn or split. check those out first. If both of those are okay, then i'm afraid you have no choice but to tare back into the front cover and see what is a miss.
Best of luck!
Ken

 

[BUCK]

IMO you CAN'T mis-time the Oil Pump Sprocket using a BSE Kit / Mirage Oil Pump Shaft - I concur with the Motor Mount Theory or some other malfunction - Mine vibes a little more at idle as felt at the Steering Wheel - above that it's dead smooth & certainly not louder - Morf will find it & let us know...

 

[1fast97gsx]

mine didn't really get louder either....

 

[Morphius]

I agree with Buck on the oil pump sprocket...... that you can't mistime it. How can you if there is no balance shaft attached? I used the shortened Mirage shaft. I set the belt with the motor out of the car and triple checked it, so I know it's right.

Motor mounts...... I'd swear on my life I checked them before I did the install, but maybe one or both were damaged after I installed the motor. Entirely possible.

Regarding mounts..... for those that have had a mount go bad....... how bad was the vibration? Comparable to a out-of-time b-shaft? I'll look at the front and rear mount. What about the drivers side mount? ANyone had that go bad and what was the affect?

 

[BUCK]

There are a buncha Threads about guys with BSE Kits who went to the Poly Motor Mounts & complain about excessive Vibes.

 

[Bd1000Eclipse]

When I swapped a 4G63T into my GGSX, I took the opportunity to liberate the balance shafts from the block. Soley because I intend to beat on the car and it'll be my winter driver, so I don't want to have to take it apart in the middle of the winter should the something go bad.

I'm confused.. So removing the balances shafts means you can beat on it all you want and it wont break?

 

[Defiant]

I'm confused.. So removing the balances shafts means you can beat on it all you want and it wont break?

No, it just means you have one less timing belt that can fail (and foul the cam belt on its way by), and ...um... five? fewer bearings that have to be supplied with oil and are susceptible to failure. Some think there's a power gain to be had from not spinning the Silent Shafts, but I don't know if there's really a lot of gain there. I'd suspect less than 7hp.

 

[heavyD]

I got the balance shafts removed and at the same time installed motor mount insterts (front & rear only). I can just barely detect a little vibration. What I do notice is that the engine oil pressure reads higher at all RPM's. Definately one of the best mods you can do to the 4G63. Sounds like something is loose inside the engine.

 

[mavisky]

did you eliminate the front one too?? i mean i know its a long shot, but i can't think of anything else that would cause that much vibration. and it sounds just like my girl's car when her front one let go and we didn't notice it for a day or two.

personally so long as my idle is at 750 or higher i notice no more vibration than before, if my idle goes to 500, then it shakes like a lumpy cammed v8.

 

[Enraged78]

Just a little FYI, when I removed the balance BELT from my car, it behaved quite well. The shafts stayed in, and I noted a small amount of vibration at 750 RPMs and about 3,600 RPMS. The car was easier to rev and seemed very happy about the whole ordeal.

Now, fast forward a few months. I have the motor out of the car, apart, with new pistons and rods going in. Both balance shafts are out, motor mounts are out, and we are in the process of balancing the rotating assembly. The motor mounts were SHOT, and the crank was out of balance by about 8 grams, which is a decent amount. Got poly bushings, and balanced the crank down to about .2 grams. Flywheel was in balance (amazingly), but the crank pulley was out of balance by about 3 grams.

Now, with all of that interia spinning around, and with Mitsu doing a very poor job of balancing a rotating assembly (and the need for balance shafts to begin with), it's not very hard to imagine one motor out of a few being more out of balance than another. Factor in the fact that Poly bushings are inherintly stiffer than the stock rubber mounts, and you have a recipe for a vibrating rotating assembly.

This, however does not explain the noise you have. How's the car run other than the noise? Does it stumble? Check Engine Light? Misfire? There has to be something else going on here.

Matt.