How many of you with no balance shafts on an unblanced motor are still running?

Boostd4 · Mar 20, 2003

I just got a little scare-

One of my friends knows the Sound Performance guys well, and one of the techs used to be a tech for Eagle back when 1G's were NEW, then he worked for AMS, now he works for Sound Performance.

He said that the 4k harmonics will grenade a no-balance shaft having 4G63T in no time unless you get the reciprocating assembly balanced by a shop. He's watched it happen many many times (so he says).

I JUST finished my jdm swap and removed the balance shafts. The car runs BEAUTIFUL. I noticed ZERO new vibrations and I even just put in a Fidanza flywheel.

My question is:

HOW MANY PEOPLE WHO HAVE REMOVED THEIR BALANCE SHAFTS, AND *NOT* HAD THE MOTOR REBLANCED, ARE STILL RUNNING? HOW LONG HAS IT BEEN?

Thanks guys. I'd like to prove this guy wrong - he's awfully cocky.

Dsmman · Mar 20, 2003

I've removed my balance shafts and my bottom end is untouched. And I haven't had any problems. I don't know of too many people that would have the rotating assembly balanced just because they removed the balance shafts. :dunno: It doesn't make any sense. The balance shafts are there for driver comfort, more than anything.

Dsmman · Mar 20, 2003

BTW- if you did about 10 sec. of searching. You would of found this thread half way down the page.

http://www.dsmtalk.com/forums/showthread.php?threadid=67963&perpage=25&pagenumber=1

turbofwdtsi · Mar 20, 2003

Mine works like a champ. We also pulled my buddy's BS's out of his car a few weeks ago. We didn't align the rear pump gear, 180 out. After tearing the motor apart & realigning it, it idles like a honda now. Well as quiet as a honda. LOL

Rob

TALONTED TURBO · Mar 20, 2003

My brother is on 80k with no balance shafts

That guys theory is poop.

Boostd4 · Mar 20, 2003

Dsmman said:
BTW- if you did about 10 sec. of searching. You would of found this thread half way down the page.

http://www.dsmtalk.com/forums/showthread.php?threadid=67963&perpage=25&pagenumber=1

Yea, I read that thread, thank you. I wasn't asking for a discussion on the matter, I was taking a poll.

I know the reliability/performance issues with the mod, I just wanted a list of people who have done it WITHOUT balancing the motor, and their mileage since.

One guy says 80k.. that's awesome... seems like everyone else is under a year before problems... that's not so cool.

greenstreak · Mar 20, 2003

I haven't ever heard of someone with their balance shafts pulled having a problem. :dunno:

Van · Mar 20, 2003

Zip... flamesuit on.

Alot of people seem to have alot of little problems with their dsm's. You can't directly say that it's been the bs elimination that did it.

Also, some people pull them and say it's the same. However, that's the exception and not the rule. Many, many more say it's very buzzy about 3300rpm or so. In my opinion, any vibration that can be felt is not good, period. It shakes things apart and extended vibration frequencies can also weaken some things.

I find it interesting that our two dsm's are both daily driven, mine runs 12's on pump gas at full street weight (hers is lightly modded) and our dsm's have both been virtually trouble free and our bs are still in.
Coincidence or not?

Mine will be staying in until I can balance the complete rotating assembly. Even then I'll be getting a nice harmonic dampener for it.

But please do as you will, because my opinion is in the minority here and I know it. I don't really give a fuck because my dsm's seem to be way more dependable than most and the balance shafts are still in.

MNGSX · Mar 21, 2003

It's simple

Are the balance shafts part of the main rotating and reciprocating assembly?

No.

They are driven off a belt any thing they cancel out is only reduced as mesured between the motor mounts and frame. Any vibration produced by the crank rods and pistons still occur between the bearings regardless if its in phase (therby cancelled out) with the b-shafts or not.

It's effect is still on the bearings. Retaining a harmonic dampener is a good idea. I'm surprised that these companies even designed these without one.

Precise engine balancing will decrease vibration at all rpms and phases of rotation. However it won't completely eleminate the inline fours inherent vibration that the b-shafts are designed to cancel out. Once again cancel out not prevent or eliminate. They don't really balance the lower end they are counterbalances designed to cancel out vibrations to the frame and ultimately a new car buyers buttocks.

About our flywheels, pullys and balancers. They can/should be balanced seperately. There are no counterweights designed into these to counter an inbalance somewhere else.

On balancing.

http://www.dsmtalk.com/forums/showthread.php?s=&threadid=84401

http://www.babcox.com/editorial/ar/eb10330.htm

Mirageman · Mar 21, 2003

Shakin without the BS

My 6-bolt had them them removed and not balanced on a new rebuild. At anything below 2500 it vibrates like a 2.2 Mopar, enough so that the images in the mirror are fuzzy. My motor mounts are stiffer, but it is annoying in low speed driving. 3000 and above is only slightly worse than stock. I think rebuilders like to eleminate the BS because they don't like dealing with the install of new bearings, a PITA job. I would keep them in . As for reliability, look at all the 100K+ engines with BS in them.
Is it normal to have a shaking engine below 2500?

TALONTED TURBO · Mar 21, 2003

Re: Shakin without the BS

I took mine out, I hardly feel any vibration at all, in fact, unless if someone took them out with no one telling me I dont think I could tell the difference! But thats me!

MNGSX · Mar 21, 2003

There are alot of varibles on this.

"My 6-bolt had them them removed and not balanced on a new rebuild. "

Not balanced. Key word a conrod (big or little end) or piston assembly (piston, pin rings) could have weights alot different than the other. This could be increasing the vibration.

"At anything below 2500 it vibrates like a 2.2 Mopar, enough so that the images in the mirror are fuzzy. My motor mounts are stiffer, but it is annoying in low speed driving."

Stiffer mounts. I'm doing window weld for now.

"I think rebuilders like to eleminate the BS because they don't like dealing with the install of new bearings, a PITA job."

I knocked mine out and put them back in in under 5 minutes. Its easy for a rebuilder since the block is out of the car.

"I would keep them in . As for reliability, look at all the 100K+ engines with BS in them. "

Your average 100k+ engine has never seen and upgraded turbo, cams, and many drag launches or the stress of sombody reaching for 3.5 zero to 60 times. If you are really building a firebreather and let that baby roar on a regular basis I don't care how well you built it. You are eventually going to wear something out and the worst case scenario is breaking something.

I have seen a v8 street and strip car that runs high 10s it made it to 120k still purring like a kitten but. He had to valve seals, re-ring and do bearings at 80k. He used synthetic and good filters. The bore just needed new crosshatch to break in the new rings and the crank was unscored- in spec and was repolished polished in his garage.

"Is it normal to have a shaking engine below 2500?"

If it was'nt balanced it could shake below 2500 with the balance shafts in or out. With all the shaking your describing I bet if you put the shafts back in there will still be many other 4g63's with shafts smoother than yours.

Gonzo2 · Mar 21, 2003

Van said:
I don't really give a fuck because my dsm's seem to be way more dependable than most and the balance shafts are still in.

I didn't give a f*** either, thinking that my DSM was way more reliable with the balance shafts in. That is, until I threw a balance shaft bearing, busted my bs belt and had my timing belt skip 180 degrees out of phase. If more dependable means there is a possibility of the bs belt breaking (which is not an uncommon occurrance in DSM's), and bending every one of your valves, then yeah, by all means, leave 'em in.

Boostd4 · Mar 21, 2003

GRr...

Well, I was trying NOT to have <sigh..> another pro/con on balance shaft removal.

All I wanted to know was how long people have ran their unbalanced motors with/without problems. A simple tally to let the facts speak for themselves.

Opinions are BS. Let the ends justify the means. Numbers don't lie - if there are 50 people with no BS on unbalanced motors with no problems and 1 guy who blew up, then there you have it. It could be the other way, too...

I just wanted to see how many people who have FIRST HAND experience are still running unbalanced, problems or not. Regardless of who you worked for or how many physics classes you've had.

Blackboost · Mar 21, 2003

Not to brag about this, but I have removed them from a LOT of cars and they're all running very nicely.

Do it and move on to the next mod.

stevep · Mar 21, 2003

Boostd4 said:
One of my friends knows the Sound Performance guys well, and one of the techs used to be a tech for Eagle back when 1G's were NEW, then he worked for AMS, now he works for Sound Performance.

Let me know who this guy is, so I can keep my car away from him. He's full of it.

Steve

Brandon92DSM · Mar 22, 2003

Well I took both balance shafts out of my car and it runs fine. I installed Prothane motor mounts at the same time, so I cant comment on how much more vibration could be atributed to the B-shafts alone.

MNGSX · Mar 25, 2003

Pics of my homebrew stub shaft.

http://www.angelfire.com/theforce/mngsx/6bolt.html

You other 2g guys still running 7bolts look at this and start looking for a 6 bolt to rebuild.

http://www.angelfire.com/theforce/mngsx/7bolt.html

MNGSX · Mar 25, 2003

I'm over my bandwidth. Bookmark and comeback later.

MNGSX · Mar 25, 2003

Back Up!

How many of you with no balance shafts on an unblanced motor are still running?

Boostd4

Dsmman

Dsmman

turbofwdtsi

TALONTED TURBO

Boostd4

greenstreak

Van

MNGSX

Mirageman

TALONTED TURBO

MNGSX

Gonzo2

Boostd4

Blackboost

stevep

Brandon92DSM

MNGSX

MNGSX

MNGSX

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