Balance Shaft Elimination Questions
Evolved Member
Joined: Jun 2006
Posts: 6,902
Likes: 151
From: Grand Island, NE
my worst experience was with the 6 bolt motors. they become vibration machines. virtually everything has the ability to vibrate off. had oil filters spin off twice at 80-100mph. not fun. turbo bolts that simply would not stay tight till they were tie wired. and flywheel bolts backing out and having to pull trans to fix it twice as well.
As for the oil filter coming loose all Mitsubishi engines had a habit of doing that twenty five years ago. My brother-in-law had a Chrysler minivan with a Mitsubishi V6 and every time he arrived at my driveway I'd notice fresh oil and reach under and tighten his oil filter.
running no balance shafts is the only time I had problem with filter coming off. it doesnt happen with balance shafts. first time it happen I had a 2.5 downpipe that must have been glowing red. at 80mph I suddenly saw a 50 ft flame from the side of my car. scared the crap out of me. came to a stop as quick as I could. used the shirt on my back to get the fire out. the paint burned off all the plastic side skirts and rear bumper. pretty memorable experience.
My friends 2g GSX lost the oil filter WITH balance shafts, twice. Rebuilt the motor, without balance shafts, torqued the oil filter stud to spec in the OFH with green Loctite. Haven't had an issue since. Red locate on the flywheel and pressure plate bolts, torqued to spec, no issues with those coming loose. No issues with 5th gear either. Trans was built by Shep to "stage 3" specs when we built the motor. Prob has about 8-10k miles on it now.
Evolving Member
Joined: Jan 2015
Posts: 250
Likes: 15
From: Hub City
Evolving Member
Joined: Jan 2015
Posts: 250
Likes: 15
From: Hub City
It wasn't like that until a Civic dropped in my lap. Once I had a daily driver, it was on like Donkey Kong.
My friends 2g GSX lost the oil filter WITH balance shafts, twice. Rebuilt the motor, without balance shafts, torqued the oil filter stud to spec in the OFH with green Loctite. Haven't had an issue since. Red locate on the flywheel and pressure plate bolts, torqued to spec, no issues with those coming loose. No issues with 5th gear either. Trans was built by Shep to "stage 3" specs when we built the motor. Prob has about 8-10k miles on it now.
Exactly what Kaj said. Jeez.
Friends car had no issues. Except the filter coming off. Came apart with plans to make power. Not because it broke. Internals looked great, timing was all perfect..
I have NEVER seen an oil filter come off on any other vehicle. Except for his DSM...lol
Friends car had no issues. Except the filter coming off. Came apart with plans to make power. Not because it broke. Internals looked great, timing was all perfect..
I have NEVER seen an oil filter come off on any other vehicle. Except for his DSM...lol
Last edited by letsgetthisdone; Jan 19, 2017 at 06:23 AM.
That thing would be on Craiglist faster than you can say "Don't low ball me, I know what I got".
Evolved Member
Joined: Mar 2008
Posts: 2,110
Likes: 320
From: Croatia
my worst experience was with the 6 bolt motors. they become vibration machines. virtually everything has the ability to vibrate off. had oil filters spin off twice at 80-100mph. not fun. turbo bolts that simply would not stay tight till they were tie wired. and flywheel bolts backing out and having to pull trans to fix it twice as well.
the heavier the piston is the worse the problem is. and the 2.4 is markedly worse over the 2.0.
I also build transmissions and on evo8/9 see huge problems with 5th gear that can only be explained as harmonics vibrating things. local here had 5th gear syncro wear out in 100 miles three times in a row. shep built trans. first two times he was required to send trans back. half the transmissions I take apart have 5th gear completely worn out. including the splines where the gear attaches to the shaft. so expensive to fix. I have see shep trans were he completely fills the threads with red locktight to fight this issue. I fix it by using a good flywheel and leaving the balance shafts in.
I could go on but I am not getting anything here. I cant stand when people to want to gain knowledge. its very aggravating to me,
the heavier the piston is the worse the problem is. and the 2.4 is markedly worse over the 2.0.
I also build transmissions and on evo8/9 see huge problems with 5th gear that can only be explained as harmonics vibrating things. local here had 5th gear syncro wear out in 100 miles three times in a row. shep built trans. first two times he was required to send trans back. half the transmissions I take apart have 5th gear completely worn out. including the splines where the gear attaches to the shaft. so expensive to fix. I have see shep trans were he completely fills the threads with red locktight to fight this issue. I fix it by using a good flywheel and leaving the balance shafts in.
I could go on but I am not getting anything here. I cant stand when people to want to gain knowledge. its very aggravating to me,
Naw. We built the 2.0L, FP Red JB, makes 540whp and 490wtq at 28psi, creeping to 30psi out the top, running the external tial MVS with 25psi of spring. We couldn't get more boost out of it on the dyno. I think it's the 2.5" down pipe. It's a fun car.
I really have to explain the 100 reasons an engine WITH balance shafts might vibrate a filter off?
I will start with the top three. 1. There are prolly 200 posts in this forum from people who did a timing belt job and mis-timed the belts. this causes MORE vibration than an engine without balance shafts. 2. There are a whole slew of reasons an engine can become unbalanced internally after an idiot would be mechanic makes a mistake. mismatched set of pistons. I have run pistons that were 26 grams unbalanced. That causes more vibration than no balance shafts. 3. Third also very common reason. Clutch material can break away causing very large imbalance.
So in conclusion saying you had a friend that had a car that had balance shafts and vibrated oil filters off is simply a poor mechanic drawing the wrong conclusion.
I will start with the top three. 1. There are prolly 200 posts in this forum from people who did a timing belt job and mis-timed the belts. this causes MORE vibration than an engine without balance shafts. 2. There are a whole slew of reasons an engine can become unbalanced internally after an idiot would be mechanic makes a mistake. mismatched set of pistons. I have run pistons that were 26 grams unbalanced. That causes more vibration than no balance shafts. 3. Third also very common reason. Clutch material can break away causing very large imbalance.
So in conclusion saying you had a friend that had a car that had balance shafts and vibrated oil filters off is simply a poor mechanic drawing the wrong conclusion.
unfortunately dont have that data. all gearbox rebuilds are boxes that were delivered to me. I can say I have opened a dozen evo 4 boxes. not a single one had a problem with 5th gear. I suspect the factory flyh wheel on the 4 is far better at absorbing vibration. The 8 flywheel was lightened up quite a bit.