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recian
01-05-2013, 07:24 PM
After a pretty lousy day at the junkyard all I found was a cam and some original rockers (no 1.8s for solid lifters) As I searched for the info on that I came across old posts about balance shaft deletes. I'm curious from someone who's done it is it worth it? What did you do? just leave the belt out? How did the engine feel afterwards?

Acuta73
01-05-2013, 11:43 PM
Many people will say GO with the delete.

I say don't.

WHY? My short block was done by an SCCA engine builder. His rationale was simple: The small Hp gain for the delete of rotating mass wasn't enough to offset keeping the engine smooth.

The alternative is go ahead with the delete, but have the engine balanced. Fair chunk of change there! Nevermind the pain in the ass screwing with bits and pieces for the delete...

LSR Mike
01-06-2013, 07:17 AM
If you are going to be a daily driver, don't bother, it's $15 in parts but a lot of work.

http://www.vfaq.com/mods/balance-shafts.html

manorchurch
01-06-2013, 10:13 AM
After a pretty lousy day at the junkyard all I found was a cam and some original rockers (no 1.8s for solid lifters) As I searched for the info on that I came across old posts about balance shaft deletes. I'm curious from someone who's done it is it worth it? What did you do? just leave the belt out? How did the engine feel afterwards?

There is not much of a HP gain from it, but if you do a rebuild, you might as well take the crankshaft for balancing. After that, pulling the balance shafts and plugging the oil gallery is just a matter of course -- why would you leave driven rotating mass in place that no longer needs compensating? You might also weigh the assembled rod-and-piston sets (including bearings and rings), and gingerly remove metal from the three heavier sets (by grinding off casting "fin" metal on the rod) until all four weigh exactly the same. Without real fancy machine tools, I think that's about as far as your basic amateur (me) can go towards eliminating out-of-balance conditions produced by reciprocating mass.

Maybe it's not a major benefit, but if you rebuild your engine, why not?

I've always wondered what Mitsubishi did in the manufacturing process that made it cost effective to add 20 pounds of spinning steel plus a pinion and belt. What the hell, why not balance the cranks when they're turned? But then, sounds easy now, maybe not so easy in 1989.

archinstl
01-06-2013, 12:21 PM
My engine is a reman from Jasper, which has (apparently) always deleted the balance shaft feature. This was done some time ago - 2002, so I do not know if that is still current practice. Frankly, I never noticed any difference in "smoothness" between the engines. Perhaps it was more apparent in passenger cars than the trucks?
I've owned my Swiss-cheese chassis Sport cab since new in 1988.

77amc
01-06-2013, 06:36 PM
I did mine and it was a SNAP! Only felt a slight shake at under 800 rpm's

I have a guy here that can balance to ZERO if you want. (2g is a penny) BUT He's 200.00, and another place (Bullet cams) charges about 175.00
Well worth it if you ask me, and guy one is going to do my 4.1 Buick V6 (they can be a challenge)

Jasper does it to save on $$ each engine that needs a balance shaft.

That's pretty interesting that a racer builds an engine with excess rotating mass that the engine doesn't need..
Usually they go to extreme lengths to make EVERYTHING as light as possible.

E

77amc
01-06-2013, 06:37 PM
HOW in the world did I get that avatar?
i didn't do that.
E

pennyman1
01-06-2013, 06:51 PM
but you are lovin that avatar, aren't you?

manorchurch
01-06-2013, 06:58 PM
I wonder how much out-of-balance weight it takes to produce noticeable shake/roll at idle, and how much that amplifies into wasted engine power at speed? The machinist who balanced the crank most recently said he drilled-out a 17g correction, which he seemed to think was quite a bit.

LSR Mike
01-07-2013, 06:51 AM
The balance shafts are there to compensate for an inherent harmonic condition in a 4Cyl Inline motor, they all shake a bit even in the most balanced of setups.
The shafts are there strictly for your butt.

77amc
01-07-2013, 09:42 AM
but you are lovin that avatar, aren't you?

Don't get me wrong, I like Fry..
I seem to have several things in common with him, and it seems that some of my friends could be the other characters..
Hhhmm..?

E

manorchurch
01-07-2013, 12:18 PM
The balance shafts are there to compensate for an inherent harmonic condition in a 4Cyl Inline motor, they all shake a bit even in the most balanced of setups.
The shafts are there strictly for your butt.

Smart ass.

camoit
01-07-2013, 03:26 PM
Smart ass.

It's true,,, People don't like there tooshy to be numb when they get out of the truck. It's the pins and needles when the feeling comes back they can't stand. It's not polite to scratch your self in public. :)

LSR Mike
01-09-2013, 07:07 AM
Smart ass.

Thank you! :-)

manorchurch
01-09-2013, 07:11 AM
It's true,,, People don't like there tooshy to be numb when they get out of the truck. It's the pins and needles when the feeling comes back they can't stand. It's not polite to scratch your self in public. :)

Pretty good (and interesting) Wikipedia article describing the 2nd order harmonics created in an inline 4-cylinder engine.

I feel stupid that it never crossed my mind that harmonics would be generated, and that balance shafts are actually a work of genius, not a worthless sub-system to be removed. Live and learn (especially now that there's not much time left for either :-))

http://en.wikipedia.org/wiki/Inline-four_engine

manorchurch
01-09-2013, 07:12 AM
Thank you! :-)

Yup. You were right; I was wrong.

camoit
01-09-2013, 11:54 AM
HOW in the world did I get that avatar?
i didn't do that.
E


I stuck it in there about 2 months ago. Got tired of seeing a blank hole. It was the only thing I could come up with to match your user name.

naci777
04-19-2013, 10:16 AM
Hi guys..My car engine is so superb but i do not know that how the balance is deletes oil of the engine is discharged.Any body tel me how the oil is stooped for discharged?

BradMph
04-19-2013, 11:22 AM
Wha? (scratching head)

LSR Mike
04-19-2013, 02:25 PM
you rotate the bearing 180 degrees to block off the oil hole.

camoit
04-20-2013, 01:36 AM
Wha? (scratching head)

French to English, I think. He is in Canada. Fordbushi's neighbor.

BradMph
04-20-2013, 05:16 PM
le canadian ae' :grin:

PowerRam348
05-10-2013, 12:45 AM
i deleted the balance shafts when i overhauled my motor and there was a noticeable difference in how fast it accelerated. but, i did have my rotating assembly balanced. mine is a daily driver and i got better gas mileage.

ikeepzitclean
05-11-2013, 01:42 AM
Camoit suggested we do it on mine, since machine shop messed up and caused my oil pump sprocket to drag da engine to a point where it seized. So we went to machine shop and made da owner order me a delete kit, then we installed it in less than an hour. motor was out of my truck tho. Haven't had a chance to drive it yet, just put da motor back in yesterday, but it seemed to rev. up easier and it's smooth :grin: i'll see how it feels when i get it on da road.

internal pic after removing balance shafts below..

t8erbug
09-03-2013, 08:11 PM
I'm doing the balance shaft delete on my motor this week sometime. Does anyone have a quick step-by-step of how to do it. I already bought the kit and I'll be doing the timing belt while I'm at it. This project will be a first for me so I'd appreciate all the help I can get! Thanks in advance!!

BradMph
09-03-2013, 08:25 PM
You can probably find a YouTube video on the subject

camoit
09-03-2013, 09:25 PM
I'm doing the balance shaft delete on my motor this week sometime. Does anyone have a quick step-by-step of how to do it. I already bought the kit and I'll be doing the timing belt while I'm at it. This project will be a first for me so I'd appreciate all the help I can get! Thanks in advance!!

Look in the tech section. I think we did a little wright up on it.

ikeepzitclean
09-08-2013, 10:24 PM
these are the only pix I can come across related to the balance shaft delete kit. I need to figure out a way to get my other pix (so I can start my build thread too), until then here's the kit i got (in the 1st pic)..

ikeepzitclean
09-08-2013, 10:44 PM
another thing I've come across on youtube in my attempt to familiarize myself more w/ DSM motors is this video. It explains how to do a balance shaft elminitation. best video I found for this procedure so far and this guy really knows his stuff and he knows DSM's very well IMHO.. check out his channel. enjoy!

http://www.youtube.com/watch?v=LR-1adDayQY