Balance shaft deleting, for economy?

[19bonestock88]

So, I've been reading a little into modding my new to me Nissan, and there are apparently many ways to gain power(intake, header, exhaust, etc) it turns out that on the QR25DE engine, it's balance shafts are spun by their own separate chain, and that chain powers nothing else... I never really considered this on the Malibu I had, as the BS chain also ran the water pump, but Nissan faithful(Mostly in the Sentra SE-R crowd) claim a gain of 6-8whp by simply cutting and removing the balance shaft chain, presumably while the oil pan was off anyway due to rust(they supposedly rust out)...

Would this aid engine efficiency, albeit at slightly higher NVH?

[Stubby79]

I don't see it making you much more efficient.

There will be a tiny bit less drag on the engine/less friction. So little that I doubt you'll notice it.

There will be less weight to spin up, so you will waste a bit less energy as you accelerate. That might be noticeable enough if you do a lot of city driving. If you spend most of your time cruising on the highway, it will be negligible.

[Fingie]

the ride'll be bit harsher, but I think it's not a big issue.

[skyking]

Not something I would do, myself. It is small potatoes in return.
I'd want to see back to back dyno tickets before I'd believe that claim too. Just like ecomodding, if it is not properly documented it didn't happen

[19bonestock88]

I agree, it's a small gain if anything... I wouldn't drop my oil pan to do the mod, but I'd likely try it if my pan were off anyway, and it looked easily doable...

In the LSJ community(Cobalt SS and Ion Redline), doing neutral balance shafts(non weighted) is known to be good for around 5whp, but that's on a 2L engine that can turn over 7kRPM in stock form, and the larger 2.5L engine only turning 6200 might not notice it as much, and were only talking peak gains at near redline... I'll try and find some dyno evidence of this doing anything...

Now, normally, I'm cruising well below 2k, and this might not help too much, but as the engine spins up climbing a hill(can't help it at all, CVT programming) this might help slightly... If nothing else, it'll help in situations which require quick acceleration, and if done at the same time as installing a different oil pan it's essentially free...