Looking for some balance shaft information
 

I have done a ton of research and I can't find anything on the second gen balance shaft removal. Everything comes up is just first gen, I need to have the car back on the road tomorrow Friday the 9th. So I'm hoping somebody could give me some information as to whether or not someone else with a 2nd gen has done it and what they used to plug the oil passage. I appreciate any info from people who have actually done it.
Thanks everyone!

The motor is internally balanced with 2 balancer shafts and 10 crankshaft counterweights. This thread is a bit old now, but please don't do this unless you know what you're doing and rebuilding a better motor than Toyota did. From the fact that you posted this to begin with.. I'd say that's not the case, and it would be in your best interest not to remove them.. Not trying to be rude, just don't want you to destroy your car in the hopes of picking up a few (realistically unnoticeable) hp.

It would be a lot easier to just throw on a lightweight crank pulley, and it won't destroy your motor.

Waaay too late, balance shafts are long gone and the car runs incredible with out the assembly. Over 8,000 miles since the removal and not one issue. Thanks for your concern tho

Good deal. Seen too many guys ruin their rides on the Mazda forums by removing these, didn't want the same fate for you. What kind of benefits have you noticed?

So far not much as far as MPG's but the cars top end maxed out at 138 before, now it quits pulling around 153. That's an impressive difference. It revs faster and is definitely peppier thru all the gears. I should mention I have a lightened flywheel installed so I think the combination coupled with the intake and exhaust helps. I personally don't have any of the vibrations that others with earlier Gen's have said they got after removing the balance shafts. So far I don't regret pulling it out at all, and its not like I couldn't just throw it back in if need be.

Did you do anything to help balance it out after removing the balancers? Definitely can believe the rev's. Upgrading the crank pulley on my tC made it rev quicker and pull harder. Can't wait to do the LWFW/Stage 1 clutch as well - the combo was one of my favorite upgrades on my 6 - not pulling the trans until it needs a clutch tho - hopefully not for another 100k or so lol.

No not a thing. All the research I did said that the balance shaft was primarily for vibrations that you can feel inside the vehicle and that no damage would occur because the crankshaft balancer was what is actually "balancing" the motor. I have thought about upgrading the crank pulley just as a precaution and to help free up a little bit more power

What crank pulley did you go with?

I went with the Agency Power. I got it for $125 from FastScions but found out afterwards that they were a bit cheaper direct from Agency (polished only if there's any left) as they were closing them out. It's a nice piece and very easy install, can't really see it so I don't really care what color it is lol.

Link in my thread to the installed pic: https://www.scionlife.com/forums/sci...5/#post4282845

@ Agency: https://www.agency-power.com/shop/li...lley-scion-tc/

Hmm, that's just a pull not a damper. I was hoping it was both. I'll have to look into it some more

Well.. with most internally balanced i4's (that have their balancers still in place) you don't need an external harmonic damper/balancer like you do with v6's and v8's (FWIW I had a heavier Fluidampr underdrive pulley on my 3.0 Mazda as it was properly dampened for that application). Your case might be different with your internal mods. But the stock unit is not 'dampened' or specially balanced, it just has a rubber ring to help eliminate NVH. Honestly I like the 0.1% more noise this part makes being on than more than the stocker, and I don't have to worry about that rubber ring separating while driving and causing bigger problems. IIRC this dropped about 3-4lbs from the crank by itself. Nobody makes a 'damper' for this motor, I looked for the hellofit when I was pricing my options out, and there was nothing - only lightweight pulleys from Agency and NST.

Here's one
https://www.summitracing.com/parts/a...hoCuc0QAvD_BwE

That's for the 2AZ, not the 2AR, as per ATI's site. They don't make one for the 2.5l.