To Balance Shaft Or To Not Balance Shaft?

[navylife59]

Ever to increase the knowledge of out Member's I came across some good information on the topic of removing balance shafts in an inline engine. Is this really a good idea? Drop the rotational weight and reclaim lost horsepower, right? Yes and no. Yes you will reclaim wasted HP but at a price. Second Order harmonics will limit power in the higher RPM band and soon destroy your engine. According to Kenny Tran of Jotech Motorsports and Scion Racing/Nitto tC fame, removing the balance shaft on the 2AZ-FE will shorten the life of the motor drastically, kill the top-end, and in high HP motors will cause the crank to flex. The crank flex will cause increased friction and lower HP. This was evident when the Leslie Armendariz Scion race car lost several tenths in the 1/4 mile are they removed the balance shafts in their 400+WHP N/A 2AZ-FE. Per Kenny's advice, the lost tenths returned once the shafts were reinstalled.

Here is a short and simple explanation of the engineering principles behind balance shafts.

Wapedia - Wiki: Balance shaft

[Redneck4csa]

Navy, weren't we having a conversation about this before?

[navylife59]

Yep. I am just slow to post.

[Redneck4csa]

I think that was brought up when I was considering buying that 2AZ-FE that a guy had on here for sale.

[navylife59]

Trust me, I would love to wrap it over 9K RPM and was sorely tempted to do the delete. It would have been great for the 2~4 months that the motor would have been running. Something about ruining an engine that I have spent over $8K for.

[Redneck4csa]

Is that what your new motor cost?

[navylife59]

$5200 for the long block
$1900 for the head work
$700 BC cams
$300-$400 for the +1mm high RPM valvetrain
$670 for Descendant Intake
$200 for Descendant fuel rail

Not to mention the undecided forced induction factor.

[Redneck4csa]

I'd really like to see you take on a turbo project. I would definitely take alot of your cues. Plus, you could think of some new ideas for custom parts that other may be interested in...

[navylife59]

Well, this project might just change to that. Been watching the Legends of Nascar and the Dale Earnhart story. The little Misses is freaked out about me road racing with so many cars. She fears the odds. We watched Pass Time last night and she said that she much prefers that I drag race as the odds are better that there won't be a crash. Just may have to go with that turbo kit. Been reading up on the Jackson-Dawson Racing TC2 Scion tC. I firmly believe that they are doing so well because of the S/C.

[Redneck4csa]

So, you're thinking about going with a turbo kit but are also wondering about the power that the Jack-Dawson tC has due to the supercharger?

[navylife59]

Christan Rado is kicking but with his big turbo for Time Attack because that racing is all balls to the wall cutt'n thru the corners for time. With NASA, SCCA, GT2type racing it as about making passes which are sometimes in turns. This is where the S/C shines because there is no lag and the power is very predictable.
Imagine braking early then pouring on the power to pass someone in a hairpin turn by darting towards the inside of the turn. There is no time to spare for a turbo to spool and heaven forbid that the boost controller has a hiccup. I love 3rd gear on my car. This is where I have full control of the powerband because this gear is so long. It is fun to enter behind someone on the highway in 3rd holding about 4 grand on the tach then rocketing past them without hesitation. Yes a more powerful turbo would eventually catch and pass me but let's see them try to do that in a turn, consistently. From what I see, when Rado does go up against the field, he does all his passing well past the exit of the turn on the straights or long sweepers. Mind you, I don't follow his racing and could be totally wrong. This is just what I have seen in a few videos.

[justplayxtragic]

Gah. I hate Chris Rado. He's annoying haha. Don't hate me though.

[navylife59]

Don't be hating the Rado. He is repping Scion, although, he makes us all look like a bunch of freaky, weird tools.

[justplayxtragic]

In all honesty, the only reason why I don't like him is cos I'm a die-hard PTuning nut, that's all.

[navylife59]

Nutt'n wrong wid repp'n da home crew.

[justplayxtragic]

I'm glad you understand