Willpegley

2006EvoIXer

iTrader: (1)

My opinion is that you don't remove just one balance shaft. The two spin in opposite directions to cancel out the front to back lateral vibrations and double up on up/down vibrations to counter the power strokes of each cylinder. So it's better to keep both or remove both. And yes on plugging if removing them, make sure to rotate the bearings to plug the oil supply.
You can open up and polish oil to push more oil through. Many do it to help oiling. None of this is done to save weight. You'll lose more weight taking a dump before racing.

kaj

iTrader: (60)

You have the rear and front mixed up: the rear gets oil supplied through a feed system which passes from the block and through the bearings. They need to be covered if you remove that shaft. The front gets it's oil feed from the balance shaft itself, so if you remove it (and install a stubby), the bearings can stay as-is, be removed, etc.

I removed the front to install an OEM stub shaft and left the belt off the rear shaft. You can remove the rear shaft but will have to flip the bearings to stop the oil feed in that area. Of course, then you have higher-than-normal oil pressure. I'm not sure if how much of a problem that would be, that's why I left my rear shaft in. No problems with it.

I removed the rear belt because the last one I changed was frayed and I was afraid one may take a crap and kill an engine. I don't daily the car, so it was worth it for me. Cliffnotes: I deleted a point of failure. The front had to be done, since I was disabling the rear.

Evo8cy

To the o.p, since you may confuse yourself with which one is the rear and which one is the front, the one behind the oil pump sprocket gets replaced with stub, the other on the upper left gets completely removed and the bearings rotated so that their oil holes do not align with the oil gallery, use the blocking plate to block the hole. The slightly increased oil pressure will not be a problem.


Here is a thread to help you out, just bear in mind that the VR4 engine sits with its front case on the opposite side than on an evo 4-9.

http://www.galantvr4.org/ubbthreads/...82&Main=850769








Marios

kaj

iTrader: (60)

How is that supposed to be less confusing?
:P

Evo8cy

If what I posted confuses you more then you need to either re-think it or find more info online for it, the same should be done by anyone else who is confused by something as simple as my post.
The side of the front case does not make any difference to where the balance shafts are located on the front case, and that is also why I explained where each balance shaft is located on the engine and what can be done with either.

Having the engine on a stand also makes no difference on which side you turn the stand.


The pictures are there as an illustrative aid.





Here is some more illustrative material :
















Marios

kaj

iTrader: (60)

okay Marios

Willpegley

2006EvoIXer

iTrader: (1)

The vibrations you get is from the pistons moving up & down. Balance shafts reduced those vibrations internally inside block. The frequency of vibrations varies with RPM (2X). I think your engine mounts will absorb most of those vibrations, so you probably won't notice the extra vibrations.

kaj

iTrader: (60)

Nah. Lots and lots and lots of us run no balance shafts. Ideally and personally, I'd like to still have them... but after seeing the condition of my BS belt, I just didn't want to run the risk. But my situation may be different than yours: I have a brand new shortblock in the car and have only driven about 15k miles in 5yrs. So, I figure any extra wear and tear probably won't be noticed in the lifetime of this car.

2006EvoIXer

iTrader: (1)

I believe that vibrations are proportional to the power output. So if you keep power levels reasonable, it shouldn't be bad. But if you're building 800 whp engine, I would think you get free massage with every drive.

LetsGetThisDone

iTrader: (1)

Boost makes the power. Without balance shafts, a well built 1000hp capable engine will vibrate about the same as a 500hp one if the stroke is the same. You mostly only feel it at idle.

Balance shafts do not prevent wear. They are purely to reduce NVH. many 4 cylinders don't even come with them.

OP, for 900whp goals with a 6466, I suggest a fully ported head, big cams (GSC S3 or similar), and an intake manifold (Magnus V5 is solid). Head work from English Racing, 4piston Racing, or HeadGames. And/Or stepping up to a 6870 if you truly want to hit, or get over the 900 mark. 900 is pretty much all in for a 6466 on a CT9a. Also, prepare yourself for full fuel system upgrades, Dual Bosch 044's with an 8an feed and 6an return, fuel rail, AFPR, 2000cc injectors. As well as ignition, a 5 bar map sensor, etc.

kaj

iTrader: (60)

Eggcellent point. In regards to my post, I'll be more specific because I was being too lazy to keep typing : possible wear/tear on anything that may/may not be affected by potential, additional vibration that may or may not occur.



My car rattles around like a bucket of bolts anyway, so I'm not too worried about feeling car do a whole lot of anything. I couldn't imagine daily driving the thing, though. That would definitely influence my opinion a different way.

2006EvoIXer

iTrader: (1)

If you had 900whp, I'd doubt it will be a DD. You'll be waiting days for turbo to wake up.

Biggiesacks

Its really a personal preference thing, best you can probably do is find someone with a sorted out engine that has had the shafts removed to see if its for you or not. It doesn't bother me at all and i DD.