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Re: Re: QR25 Balance shafts

Barry said:


Why would someone do that??
Barry
This is why:

This is a quote taken from the mailing list, it was said by Mike Kojima, "The balance shafts are good for 7-8 wheel hp on a
QR25DE. Surprisingly the affect on NVH is minimal. I
drove a QR25 with no balance shafts and it was quite
hard to tell, except posibly at idle. Without the
shafts the vibration was still better than a KA24DE.

Since the balance shafts spin at twice engine speed,
the bearing life on these could become an issue when
the car is raced. So for racing use with a higher
than stock redline, There removal might be considered."
 

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Haha....actually right now I am trying to gather up all the tools I think I'll need. Gonna head to the store quick to get a drill bit (realized I don't have the right size...musta broke mine). I'm also debating whether or not to start tonight or wait till tommorrow. I want to start tonight but don't know if I'll have enough light (doing it in the parking lot at my apt). But we'll see!
 

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Update on the project....

I now have no balance shafts!! Project went flawlessly (except for having to go buy an E-14 socket in the middle of the project to remove the main bolts). But the good news is it's done.

I have not driven it yet though because I'm going to let the oil pan cure overnight before I add oil to it. I will add oil tommorrow when I wake up and test drive it. I also have lots of pictures and will do a writeup on it and post it. It went pretty smoothly!
 

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Ah yeah.......

Well, I officially have a running car now with no balance shafts!!! Filled it up with oil today and took it for a test drive. It is noticeablly quicker. Not really in 3rd (highest I went). 1st and 2nd it pulls VERY strong though now.

One side note, my car now takes 6 qts of oil. Oil changes are gonna be expensive now!! 6 qts, at $4.50/qt!!! Makes me think I should go back to dino oil. Write-up is coming!
 

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balanced shafts

I would like to see some dyno numbers to see if it is worth the trouble to take them out. whats the vibration level like is it bad at low rpms or at high rpms. Please more information is needed, and some pics would be great.


mike
 
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ezcheese15 said:
Ah yeah.......

Well, I officially have a running car now with no balance shafts!!! Filled it up with oil today and took it for a test drive. It is noticeablly quicker. Not really in 3rd (highest I went). 1st and 2nd it pulls VERY strong though now.

One side note, my car now takes 6 qts of oil. Oil changes are gonna be expensive now!! 6 qts, at $4.50/qt!!! Makes me think I should go back to dino oil. Write-up is coming!
I recommend 5 and a half quarts.
Barry
 

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There was absolutly no vibration difference that I could tell.

I do not have dyno numbers, but as Kojima said, they dyno'd a 7-8 HP difference without them. As far as the pictures, I'm actually working on the write-up as we speak, so I'll post it in another 30 mins or so.
 

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Barry said:


I recommend 5 and a half quarts.
Barry
5 1/2 qts did not even fill up to the "min" on the dipstick. It took 6 qts to get half way between the min and max on the dipstick. The balancer is huge, theres no wonder it takes more oil now. I just made a lot more room for it :)

BTW...I didn't even see any oil on the dipstick till 5 qts. I think it will take 6.5 qts to hit max on the dipstick now.
 
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Would it make sense to just leave the balancer in? Or maybe take it out gut it, then put the housing back in? That would definitely decrease your oil consumption. Just a thought.
 

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Re: balanced shafts

cortrim1 said:
I would like to see some dyno numbers to see if it is worth the trouble to take them out. whats the vibration level like is it bad at low rpms or at high rpms. Please more information is needed, and some pics would be great.


mike
7-8 Wheel hp difference.

Mike
 

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I don't see how you could "gut it".

But as far as leaving it in, I wouldn't. In order to get the tensioner and chain out, you have to remove the balancer anyway. Also, you would be feeding oil to the balancer, and the balancer would not be turning. I'm not sure how it would effect oil pressure and such.

Also, the thing is heavy, you are cutting down on weight by removing it, as I'm sure it weighs much more than the oil it displaces.
 
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Balancer...

Your looking at a serious operation on your car. I might yet attempt it though. I'm just not to the point where I can bring myself to do it. Call me a puddin' but I'm not comfortable doing that kind of work, YET. I wonder how much A mechanic would charge to do it...

-Steven C:eek:
 

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I'm all about getting horsepower, but on a brand new car.... man i can't bring myself to void the warrenty yet. I'll be intrested to hear a long term update. I'm looking at starting 'real' work on the car next year when i graduate.
 
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