Austarion

I wanted badly to remove my balance shafts, but I've always feared from breaking my oil pump while I'm driving, cause I didnt want to use only one bearing. For that purpose I left only the balance shaft that is connected to the oil pump, but I regrinded it firstly as shown at the picture. It is now with a cylindric shape and I hope everything will be allright. I'll post another topic when I tune my ECU :beer

That is the way I insisted mine was machined so there was no chance of problems with the oil pump alignment

um :? I thought that the balance shafts were there for a reason !!!!! :? :?

The only thing they do is smooth out the engine's vibrations while it's running. Deleting them doesn't hurt, so why not? Plus you get a more responsive engine in the bargain, which is always a good thing :)

Let's just ask OLD FART if you realy need them... even with a stroker? :D

Well I'd go with the Mitsubishi engineers who obviously thought they were a good idea at the time.

Removing them doesnt necessarily create any problems and certainly makes for a snappier response. The issue is if you remove them, the job has to be done 100% correctly or you could have get problems with the oil pump shaft.

The problem with leaving them in is getting oil supply to them. I have seen a couple of cases where the oil supply wasnt up to the task and the bearings ran dry and fooked the motor.

Each to their own. I'd always go with the preference of leaving them in but not without improved oil feed. I like the idea of machining it down though to give a more solid support but again oil feed is critical, particularly if you are going to give the motor a bit of a rev :D

what do you recommend to get the oil supply up to task?

groove the bearing surfaces to allow better flow

The 2 of the 3 motors I've removed them from (the 'rangi' way), are still running fine several thousand k's later... The 3rd died from a completely unrelated cause some 30,000k's after I built it. While I had it apart again I checked the oil pump against the clearance notes from the first build, and there was no significant wear... All 3 motors are just normal street spec, but do get thrashed pretty hard... Leads me to believe that cutting the balance shaft off and plugging the oil supply hole is an acceptable method for a street car.

ProZac wrote:The 2 of the 3 motors I've removed them from (the 'rangi' way), are still running fine several thousand k's later... The 3rd died from a completely unrelated cause some 30,000k's after I built it. While I had it apart again I checked the oil pump against the clearance notes from the first build, and there was no significant wear... All 3 motors are just normal street spec, but do get thrashed pretty hard... Leads me to believe that cutting the balance shaft off and plugging the oil supply hole is an acceptable method for a street car.

probably you had a new oil pump or not ?, cause when I rebuild my first engine cutting off the balanace shafts I did about 25 000 km's and the oil pump died because of the bearing. In my opinion you definetely need two bearings to keep the oil pump safe at any moment :beer

There is a bit of sizzle at certain revs with the stroker and if I was to start over HEAVEN FORBID :x I would leave them in BUT mod the oil supply as per Gregs method
Remember they spin at twice the crank revs