Balance Shaft Removal Quest...

[evil-G-nius]

I searched and I am looking for a tutorial for the '64. Now do you need the eliminator kit? Where do you get it if you do? Also, if I dont get teh engine balanced, if I drive say 7 hours at 100-105mph, will it cause any damage? I think I wanna remove it but I am worried...I am sick of buying engines because of this fuckin belt!!!

[krazienluv10]

ehhh u dont really need it to have the car running, but the vibration of the engine will increase...it should increase some hp, but the idle will be rougher n louder ... however i think in the long run it was cause some damage towards the engine sooner or later...i just wouldnt do it...

[evil-G-nius]

Yeah but I need her to be reliable. I dont want it to "destroy" the engine sooner than later. Seems like your damned i fyou do damned if you dont. I mean if I leave the belt on, I got the chance for this fucker to split off and screw everything up again! Then if I remove it, I got the chance that the car will break down sooner...WHAT THE FUCK!

[peanotation]

there's nothing bad about removing the balance shaft, you're only feeling more vibration, but no more or less vibration is being made. in fact it's actually safer not to have your balance shaft because the belt can break into the timing belt, and you'll get better oil pressure to everything

[manybrews]

<div class='quotetop'>QUOTE(peanotation)</div><div class='quotemain'>there's nothing bad about removing the balance shaft, you're only feeling more vibration, but no more or less vibration is being made. in fact it's actually safer not to have your balance shaft because the belt can break into the timing belt, and you'll get better oil pressure to everything</div>
not true.

first, the cars will definatly vibrate more. Moreso than any other 4 cylinder due to the lack of internal balancing. the frequency wont change, but the amplitude quadruples.
secondly, for those of us that have had to deal with this kinda stuff for 15 years, there are many problems that surface from removal of the shafts. Engine bolts constantly vibrating loose, pieces falling off, incorrect removal of those shafts, etc.
but the largest thing seen from removal of the shafts is failure of the oil pump. the upper part of the two piece gear set relies on the balance shaft for support. removing the shaft and replacing it with a small stub removes that support, and ive seen oil pumps ruined from it (not instantly, of course, but in about 20000 miles).

also, there is no noticable gain in HP. there is no load on the shafts other than their own intertia. there is far more HP lost from every other rotating piece of the engine, including the crankshaft itself.
each shaft is only about 2.2 pounds, so you save about 4 and a half.
oil pressure has never been a mitsu problem, so that is not a benefit either.

as you can see, im plainly NOT in favor of removing them. the engineers installed them for a reason, and they work. thats why EVERY car company on the planet uses them in many of their engines.
History 101; Mitsubishi engineered and patented the first balance shaft technology back in 1971... they had ALL the bugs worked out of them long, long ago.

One last thing. Ive built mitsu race motors. my best? a 425 hp 91 eclipse. guess what? it had balance shafts in it, as well as mostly factory pieces. Never once did anypart of the engine fail.
the only reason I could justify removal of them is if you built a PURPOSE ONLY race engine expected to hit 9 or 10 thousand RPMs.

[DOHCstunr]

i hear you manybrews.
but the correct stubby shaft to use is the O.E.M. stubbyshaft. it has an oiling groove in it and it won't fail, nor cause premature wear to the oil pump. its a stub designed by mitsubishi for the exact same oil pump front case.

the vibrations only happen at two specific points in the rpm range.

i have seen dyno charts of the gains. so i call b/s on the no gains statement.

you don't get any abnormal bearing wear from the deletion of balance shafts. and thats a fact.

[seth98esT]

I have removed mine and I saved about 7lbs off the rotating mass. Yes it does vibrate more, mainly at 1000RPMS and somewhere in the 3000RPM range. Other then that I dont notice any difference. It does seem to rev freer though, didnt notice an increase in power, but I can spin second gear now where as at the same psi with the shafts I wasnt really able to.

[manybrews]

<div class='quotetop'>QUOTE(DOHCSTUNR)</div><div class='quotemain'>

the vibrations only happen at two specific points in the rpm range.</div>

it happens throughout the entire rev range. you may not feel it in the car (which I dont really believe, as I can tell by standing NEXT to a car when the balance shafts are out of synch or gone), but slap a oscilliscope on it and you'll freak. Remember, Im working for mitsu. I got to see the cheesy 1977 video (made in japan) about the balance shafts during a random week I spent in mitsu training, and on it they showed a bunch of interesting stuff about them. I wish I had a link to it. lemme see if I cant convince one of the guys at the regional traning center to send it to me.
<div class='quotetop'>QUOTE</div><div class='quotemain'>

i have seen dyno charts of the gains. so i call b/s on the no gains statement.</div>

so have I. about 1-2 HP. to me, not worth it.
<div class='quotetop'>QUOTE</div><div class='quotemain'>
you don't get any abnormal bearing wear from the deletion of balance shafts. and thats a fact.</div>
I didnt say bearing wear. I said oil pump wear.
Ive replaced 2 oil pumps due to this, and this only. I have never had to replace an oil pump for any other reason (except massive catastrophic failure of the entire engine, and then only to be safe).
THATS the fact.
Will you destroy the engine removing them? of course not.
But the gains are totally outweighed by the disadvantages. I dont want my cars to buzz and vibrate. If I did, id buy a Neon.
Im not including straight out race engines/cars, because thats not realistic. Some people here may race their cars, but Id bet 99 percent of those cars spend 99 percent of their time sitting in traffic like the rest of the world. Thats when I want my A/C to work, my engine to be smooth, my check engine light to be off, and everything else on the car to function.

but hey, thats just my opinion. However, most people agree with me, which is why balance shafts are in most every engine that doesnt have natural balance on the planet nowadays

[seth98esT]

I agree with you Manybrews. I really dont know the long term desadvantages of the BS elimination and I wouldnt recommend doing it if it is your only car aka dailey driver. I drive my car a few times a week and it doesnt bother me one bit.

I only eliminated mine because I spun a balance shaft bearing and I didnt want to deal with any of that crap again so I installed new blockoff bearings and took the balance shafts out. I have no clue why I spun the bearing, my motor is weird and is probably a lot older/abused then I thought when I bought it.

[DOHCstunr]

i only used my a/c to defog my windows, an then only once a week or so to keep the system lubricated. i hated that it sapped my gas mileage and hurt my low end power when driving in traffic.
check engine lights bother me too just as much as anyone else i suppose.

i love things to be smooth as well, but as with every other mod i have done or plan to do, i weighed MY wants and needs in with the cost/ benifit analysis.
i wanted better handling and a more aggressive ride so i stiffened my chassis and upgraded to a stiffer suspension w/ lower ride hieght. I sacrificed a buttery smooth ride because of it.
i wanted a safer and more powerful brake system.
so i upgraded it, and now i have to replace pads more often. aand the pads cost more.
I wanted to eliminate wheel hop and reduce driveline loss.
so i upgraded my motor mounts to solid polyurethane. now i have vibration in my cabin.

each person when upgrading has to weigh the benifits.
My personal taste is power and reliability.
to each his own.
myself, next time i replace my timing belt, i'm going to pull my balance shafts and replace the rear shaft with the stubby shaft made by mitsu for the 4g63.
but thats just my plan.
the balance shaft belt on my 4g64 dohc killed my crank position sensor. Thats after only 12,000 miles using mitsu parts installed at the dealer. lucky for me it didn't slice my timing belt.

matts b/s belt killed his timing. as well as this guys. and in seths motor the b/s bearing spun and sent bearing material into his oil. he's lucky the shaft didn't lock up.

thats just three people of the thousands affected. so IMHO if you don't mind the vibration, and you use mitsu parts, why bother with a timbomb under your timing cover.
but others may not come to the same conclusion as me.

[manybrews]

<div class='quotetop'>QUOTE(DOHCSTUNR)</div><div class='quotemain'>i only used my a/c to defog my windows, an then only once a week or so to keep the system lubricated. i hated that it sapped my gas mileage and hurt my low end power when driving in traffic.
check engine lights bother me too just as much as anyone else i suppose.

i love things to be smooth as well, but as with every other mod i have done or plan to do, i weighed MY wants and needs in with the cost/ benifit analysis. Â*
i wanted better handling and a more aggressive ride so i stiffened my chassis and upgraded to a stiffer suspension w/ lower ride hieght. I sacrificed a buttery smooth ride because of it.
i wanted a safer and more powerful brake system.
so i upgraded it, and now i have to replace pads more often. Â*aand the pads cost more.
I wanted to eliminate wheel hop and reduce driveline loss.
so i upgraded my motor mounts to solid polyurethane. now i have vibration in my cabin.

each person when upgrading has to weigh the benifits.
My personal taste is power and reliability.
to each his own.
myself, next time i replace my timing belt, i'm going to pull my balance shafts and replace the rear shaft with the stubby shaft made by mitsu for the 4g63. Â*
but thats just my plan.
the balance shaft belt on my 4g64 dohc killed my crank position sensor. Thats after only 12,000 miles using mitsu parts installed at the dealer. lucky for me it didn't slice my timing belt.

matts b/s belt killed his timing. as well as this guys. and in seths motor the b/s bearing spun and sent bearing material into his oil. he's lucky the shaft didn't lock up.

thats just three people of the thousands affected. so IMHO if you don't mind the vibration, and you use mitsu parts, why bother with a timbomb under your timing cover.
but others may not come to the same conclusion as me.</div>

thats all good. Its your car, and I can appreciate people playing around with their stuff.

But I wanna know whos installing your balance shaft belts. they easily last the needed 60k interval. most of the time when a belt breaks and I have to fix it, the main belt has teeth torn off it, and the little belt still functions.
Someone is dramatically overtightening that little belt, I think. the tension should only be finger tight, at best.
back in the early 90s, mitsu had a huge problem with the belts on the DOHC 4 cylinders. The glue holding them together was water based, and deteriorated quickly. I saw some belts (the main belt, mind you) fail at 8000 miles. The rubber would simply fall off the backing.
they issued a recall and replaced the primary belt only with newly designed belts, and since havent had much of an issue at all. These days when I see a broken belt, its always either at higher milage (90-100k), or has been "fixed" by billybobs fixit shop.
the v6 belts go much further than the 4 banger belts, too (Ive seen 167000 on a factory belt, and it still looked okay). That probably has something to do with less extreem angles of deflection and slower overall engine speed.
anyways, be careful who you let set up your belts if they're failing at 12000 mile intervals. That little belt has basically no load on it whatsoever.

[seth98esT]

Interesting stuff, water based glue haha Nice going mitsu! When I spun a bs bearing, by BS belt was in perfect shape. I put a new BS belt, timing belt, and new tensioners/pulleys all around about 8k before it spun. I dont remember over tensioning the belt but I may have, who knows.

I have also heard on a SOHC 4g64, removing the balance shafts does cause a lot more vibration then a DOHC 4g63/4, but that is just what I hear.

[peanotation]

back in high school my bs belt failed on the way to school. i didn't even know what an oil filter was back then so i didn't know anything was seriously wrong. my school was just around the corner so i decided to push forward and try to make it. i did, and let me tell you, the vibration was horrible. it just felt really really really gnarly.

but keep in mind, that's with a broken balance shaft belt. the balance shaft is still there so i'm sure with a properly done balance shaft removal the vibration probably isn't as bad as it was for me.

just to finish up the story, i got the car towed, but the tow truck driver could only access the back of school, so i turned the car on and drove to the back. half way there the car stalled and shut off for good. bam. busted timing belt due to busted balance shaft belt.

it was dumb, yeah, but i didn't know anything.

[DOHCstunr]

yeah i was kinda pissed about the belts but it pretty much pushed me forward to my current setup.
Back then i didn't do my own work. now i do, so when something fails i have only my self to blame.

as for the v6 belts. i just did the timing belt and water pump on my fathers 6g74 diamante. has close to 100k on it.
original belt. looked great on the backside. the teeth weren't worn at all but there were some fine cracks if you bent it backwards. but i'm positive it would have gone another 40k no probs.


matt, when your b/s belt snapped back in the day the excessive vibration you felt was due to the rear balance shaft still turning w/o the front balance shaft. so if anything it was creating vibration instead of dampening it.

[evil-G-nius]

Well this is my second failed belt. The first one snapped after a tune up. The belts were fine but my mechanic said the timing would need to be replaced in a couple of months. Well that is when the first bs belt snapped, it wasnt even supposed to! No dry rot, not over tightened...nothing. Of course it fucked up the engine.
This time I may have gone over my 60,000 mile mark, I am not sure because when I replaced my engine I couldnt roll the odometer so I am not sure how many miles are on this one. But this time it snapped on the freeway and really retarded the timing. I think I will keep the bs this time too but now I know about the problem I will keep a closer eye on it

[bmxmike]

Well now mitsu makes balance shaft removal bearings so abviously it cant be that bad or they wouldn't be aiding in the removal. Dealer ship i bought my car from even offered me and asked if i wanted them removed with the install of the mitsu bearings. I don't know if they just started this or what.

[seth98esT]

Well they didnt make them for our motors or the 4g63t, the stubby shaft is made for the 1.8L motors that dont require the balance shafts, yet they use the same casing as the 4g64/4g63t.

Its not something that was inteded to use for the 4g64/63t but it fits like it should as the 1.8L motor is similar. Balance shaft belts suck, I prefer a little vibration vs balance shaft belt failure.

[bronxbombr]

Ya i been thinking about doing mine for over a year now.

[DOHCstunr]

its really not hard.
its actually a very cool expierience.
next time you have the timing belt off, just do it.

[Proto]

ill be doing this within the next couple weeks. ordering all my parts tomorrow from SBR.