StreetStarsTc

that is true. so basically light flywheel and crank pully would suffice. you wouldn't really need to delete the balance shaft.

i mean i'm also putting on polyeurethrane mounts which would add more vibration.

i think it is a good question. hope someone could answer it for us.

SVicksTC

Well motor mounts are nice but dont help with the INTERNAL vibration of the motor....I dont think you where implying that but im just saying to those who might think motor mounts are going halt not only engine movement thus reducing internal vibration.....from some one else's words: you can encase a motor in cement and its still going to have internal vibration.....hahaha

But ya with a lighter weight flywheel you would accomplish all the same that one would try to get out of removing the balance shaft....

Although my research is not fully done in this matter im going to hold off a little longer, i mean my clutch is going to go some time and with that comes upgrades and flywheel

StreetStarsTc

hmm interesting.

well i didn't imply anything about internal vibrations lol so thanks for clarifying that *no sarcasm*

and i'll be doing a manual swap very soon so i'll be pulling out my motor for convenience sake and probably will do flywheel, pulley's at the same time.

interesting thread.

engifineer

An undampened crank pulley is not the same thing as removing balance shafts, and deletes the harmonic vibration damper (not to be confused with a harmonic balancer, which our pulley does not have) which is an important part of your motor. There are millions of threads debating this so I wont go into them.

While there is some inertial momentum change with balance shaft removal, it is very, very small, so this is also not the same as a lightweight flwheel (which is a good mod). Removing rotational mass affects the engines ability to rev up and down quickly. And although many inertial dynoes mistakenly read otherwise, this does NOT free up power.. although it will make the car accelerate faster (rotational mass only affects changes in rpm, not steady state power.. which is why it can increase performance without freeing up actual hp ... also a million posts about this as well).

The main reasons for removing balance shafts is to remove parasitic drag aka frictional drag on the motor and to prevent engine failure due to the gears on them failing (this has happened in the past).

yamaha16bw

well said.

someone needs to post up that pick of the balance shaft gear that fail. it completely destroyed the journals that the shafts sit in.

rhythmnsmoke

Mine is stock. My flywheel is not though (lightweight).

bbtc06

interesting discussion...definitely watching

Ghosty44

about the light weight pulley..i recently removed mind to go s/c and when i stuck back the oem crank pulley. My car would start up and run like crap idle was low and everything and kept at it for awhile even misfire when i started up the first time..hm..do you guys know why that would happen? I guess it still happen but i pulled my ecu for ecu swap for the s/c so the tc is not running right now..

engifineer

Any time you reset the ECU it will "relearn" its idle and some other settings". This makes for a low/rough idle for a bit until you drive the car a ways. Even on a stock tC this can happen. If it does not clear up after driving a while then there may be another issue.

crush02342002

iTrader: (2)

nice thread, glad i stopped in. so heres my stupid question of the day..lol
If you lessen the rotational mass ie light flywheel will you see faster 0-60 times? Im not talking seconds but more in miliseconds. and how does this affect forced induction? I remember paul saying something to the extent of lessening the rotational mass will cause your revs to drop very quickly between gears and could hurt you when getting back into boost (ie lag)

rhythmnsmoke

I would say YES and NO. The revs do drop faster when you let off the throttle. BUT, if you drive like I drive, you don't loose boost when you shift...

thendawg

iTrader: (2)

Ill post pics of what the plastic secondary gear from my balance shaft looked like and everyione will remove them for fear of it happening to them lol - and this was only on 240-250 whp

engifineer

RPM will drop more when you let off, but you should be able to compensate.. just shift quickly

Since you are affecting changes in engine speed, this also affects changes in vehicle speed, so yes, you will decrease your 0-60 time to some degree, although to a small degree since the rotational mass of the rest of the engine, tranny and wheels far outweigh that of the flywheel.

The flywheel swap is mainly good for rev matching. And on a track (especially an autox course) it would have the added benefit of increasing engine braking. Throttle lift is used a lot in autox rather than braking in some situations. Since you decrease rotational mass from the flywheel, there is less momentum in the system, thus more engine braking.

SVicksTC

Interested in seeing this, but was this only in one isolated case, or has this been issues for others, because from what im seeing it doesnt seem to be a big concern....

crush02342002

iTrader: (2)

lol

chicotunner07

i remember seeing a video of someone who had all three mods, lightweight flywheel, lightweight crank pulley, and balance shafts removed, he reved super fast!!

j3st3r

iTrader: (1)

I dont run balance shafts Travis

rhythmnsmoke

Well hell, guess I'm going to have to come over for a balance shaft removal then if your up for it..... Then again, you are on built motor too.

I will do it on the spare motor for sure. Trying to tie up the loose ends with this Emanage Ultimate presently. I got it started and idling so making some progress. It has all to do with the injector settings.

Guest

Eliminating the balancer shaft assembly is not worth it on a stock motor, especially with the motor still in the car. To do it right, the motor should be out of the car, the complete balancer assembly, bearings, etc. should all be removed. The oil feed hole to the balancer bearing should be tapped and plugged with a threaded set screw and loctite--not jb weld. In addition if you're removing the balancer assembly to free up hp, the balancer drive gear on the crank should be removed as well--can't do that without the motor apart. This is all done on our built motors.

Yes, the balancer assembly does reduce engine vibration given the stock motor rotating assembly, but if you lightened your crank, run different rods, pistons or increase the redline, it would throw off the rotating assembly mass and the balancer assembly is no longer as effective. As far as racing motor is concerned, the less rotating mass the engine has to turn the more hp you'll free up. When you start upping the rev limiter, the less moving parts you have, the less chance for something to fail.

One of the main reasons DSM guys removed the balancer assembly is for reliability reasons. The balancer shafts on the 4g63 motor is driven by a balancer belt similiar to the timing belt. If the balancer belt snaps, it will take out the timing belt as well. So the primary reason is for realiability issues and the other reason is for freeing up hp and again raising the revs and having different components weights for the rods, pistons, etc, throughs off the effectiveness of the balancer shafts.

MrC

rhythmnsmoke

^^Good info as always MrC. That is what I was really interested in finding out about "Stock" motors without them.