In our experience using a stub shaft when removing balance shafts can increase the chances of oil pump failures. This can be caused by the lack of support provided by the rear bearing on the original balance shaft. The support is needed to prevent the oil pump gears from pushing apart and wearing into the aluminum pump housing. Once the process begins the gears can continue and wear enough to cause them to seize. During this whole process the aluminum that is being worn away can enter the clean oil stream and contaminate engine bearings and other components causing them to wear prematurely.

To help prevent this process we have come up with a way to support the oil pump gears and still remove the rotating mass. We start with a stock balance shaft then, spin it in a lathe to make sure there is no radial run out. This ensures that the shaft will spin true in the bore and not cause premature bearing wear. We then machine the weights and extra material off in a precision lathe and re measure run out to verify nothing changed during the machining process. All parts get cleaned thoroughly and are ready for installation. In the pictures below you will see the differences in the three shafts available. There are also substantial weight differences in the three shafts as seen below.



http://www.amsperformance.com/store/...oducts_id=1550

 

How many oil pump failures has AMS seen over the years with engines running the stubby shaft?

Does Buschur use the stubby shaft?

I always have to get Buschur involved lol just because they are the most trusted builder on EvoM.

Dave B, sorry to drag you into something again. But let me ask you, how many oil pump failures do you see on your motors using the stubby shaft?

 

That is why I am running the AMS shaft!

 

The more support you have the better, once again AMS proving why they are the best at what they do.

 

Great way to start a pissing match again...

Great job on AMS's part for innovation...

 

This innovation has been used many many years ago!

 

That's about the most half a$$ed apology I've seen in a while. This is AMS' thread man.

 

Take it easy fellas!

FWIW, I've had an oil pump failure. I was using the stubby shaft. I personally don't believe the failure was caused by the stubby shaft, but it is hard to say.

The point is, my response in this thread was not academic. I'm truly interested in inciting an intelligent debate. If AMS and Buschur can't debate the merits of a particular engine mod without it getting ugly, that is not my problem, and personally I think they can.

I'm sure if you guys had it your way we'd all just post, "AMS FTW!"

 

You and I both know it is NOT about them debating the merits of this product amongst themselves. It gets ugly BECAUSE of the band-wagoners having to throw in their 2 cents into the debate... For that, it's a FAIL!

 

Totally unbiased myself as i have the stock shaft, but I also would like to know if there have been many failures with the stubby.

 

how high can a fully built motor rev with the stock? and how much higher with this race balance shaft?

 

The balance shafts have little to nothing to do with how high the engine can rev.

 

I dont think that this thread is here to be debated. This is simply a part that is being used by a specific company who has seen improved results due to its use. There is nothing to debate here it is just knowledge that is released to try to help the Evo community

 

You got to love people who want to stifle a debate.

God forbid some information actually gets out there that helps enthusiasts building their own motors decide which way to go.

 

Just to clear some things up.

1. We have been using this Race balance shaft in our motors for over three years now and we felt it was another finer point to our engines that needed to be made public. Anyone that has bought an AMS motor in the past three years can attest to this option that is now standard on all EVO engines

2. Buschur builds a good motor, so does AMS. I think almost everyone can agree that they are on a level playing field and that there is no debate needed on who is better. Our track record might not go back as many years as buschur but our components, quality, service and level of achievements are as Just as high.

3. This post was not just meant to highlight another finer aspect to our engines but also to inform the EVO Community on something they should always consider when building an engine.

4. The race shaft is healthier for the oil pump, this is not an opinion but rather factual information.

I hope that can put to bed any proposed Argument before it happens. If anyone else has any questions feel free to ask away.

To those that were attempting to keep the post on track...thank you

Eric