Balance shaft elimination

[Rx3]

To make a long story short, I had a strange vibration in my car around 3K RPM. A few days later, my car died. After much cursing and troubleshooting (Mitsubishi AWD turbo engine= no free space to work. NONE! ) I found that my balance shaft belt somehow was stripped of it's teeth. All the rubber teeth fell to the floor as I got the covers off. Some of them probably took out the crank sensor. The shafts seem to move ok when I was turning the crank pulley.... so a few questions:


1) What causes a belt to lose it's teeth, yet not break? Could I have seized a bearing in the balance shafts?

2)Should I go through with the pain of installing a balance shaft elimination kit? What kinds of HP gains should I expect to see? Will the engine be more reliable (because that's one less belt to break and get caught in my timing belt)?

Or should I just put on another balance shaft belt ?


3) Just how bad will the vibration be if I take out the balancing system?



This car is my daily driver (when it is too cold/inconvenient to ride motorcycle), but I do plan to auto-x, run a few open track days, and possibly a hill climb in PA if the chance presents itself


Any suggestions on what path to take?

 

[NDgsx]

I'd remove them and leave the front shaft and bearings in place (ASSUMING they are in good condition and did not spin, you will have to look when you drop the oil pan). You can leave the front shaft in without it turning, but you won't get the higher oil pressure benifit of no BS. Pulling the shaft out with the engine in the car is a pita.
Use a mirage 1.6l stub shaft to replace the rear shaft.
Vibration is typically not that bad inside the car with stock mounts. I highly recomend loctiting everything with no BS though.

 

[2FastTSiAWD]

I eliminated the bs on my car, and the vibrations are hardly noticable. Only at idle, 1k, do you feel anything, and thats only in the steering whell really. I have stock mounts, and I did a full rebuild along with a port and polish, so I can't really say I felt a hp dif, but it elimated a belt that could potentially break and take out the timing belt, so it was worth it to me. I say go for it.

 

[RipperXX]

hey i have a question that might go along with his..

if you remove it but then have the engine balanced (all rotateing mass) it shouldn't vibrate then but then the BS will be gone too right?

 

[set3422]

i bought an used block with the front balancer shaft welded inside the block. The idiot ex-owner couldn't afford to buy some new bearings to block off the oil hole.

Originally posted by RipperXX
hey i have a question that might go along with his..

if you remove it but then have the engine balanced (all rotateing mass) it shouldn't vibrate then but then the BS will be gone too right?

 

[TSi90]

hey i have a ? that might go along with this. Where can i get a bs eliminator kit and how much are they i've never really heard of it and if theres a way around it i'd do it so let me know.

 

[Rx3]

You can get a kit from the dealership I think. I ordered mine from Talahassee Mitsubishi. Just say you are with the DSM club and they give you 25%-30% off the price. I paid $31.00, and it has all the hardware listed in the vfaq instructions for the install of balance shaft eliminator kit. Conicelli Mitsu probably has the kit too. Road Race has a kit as well. There is no "way around it". You either get the kit, or the separate parts mentioned in the vfaq (which Talahasse Mitsu says is already packaged in their "kit")

 

[set3422]

actually there's a way around it. Mike Hamilton posted on his site on how to remove balancer shafts for free. The only thing you need to get is to find a 10mmx1.25 bolt long enough to block off the oil hole on the chopped up rear shaft and a plug to seal the front shaft gear hole. The rear shaft has to be tapped deep enough for the longer bolt to go in. You would re-use old front oil bearings by taking them out and putting them back at some rotated degree, so that bearing hole would face anywhere but the block oil hole.

Honestly I wouldn't re-use bearings especially if they have high mileage, so do this at your own risk. Bearings are cheap.

Good luck

Originally posted by TSi90
hey i have a ? that might go along with this. Where can i get a bs eliminator kit and how much are they i've never really heard of it and if theres a way around it i'd do it so let me know.