GB Billet Oilpump Gears

Thread Tools
 
Search this Thread
 
Old 11-04-2008, 01:31 PM
  #201  
Elite Member
iTrader: (3)
 
AbeFM's Avatar
 
Join Date: Aug 2006
Location: San Diego, CA
Posts: 3,047
Total Cats: 12
Default

Oh, I wouldn't. I mean, I think you could, but I wouldn't.

Another set of gears seems hands down the way to go.

Travis, if you'd like, I could send you a VVT oil pump, with your gears in it, if it comes back with a set that fits. :-) And the OEM gears along for the ride, too.

While you're at it, you could optamised the radial tolerance for the VVT oil pump since it's a custom build anyway.

I'd want to know, like, yesterday, though since I'm putting one motor in tonight. I kinda don't want to pull the 2001 pump out but if you think it'll help and/or work better in the end, I'm there.
AbeFM is offline  
Old 11-04-2008, 04:26 PM
  #202  
Elite Member
iTrader: (16)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,292
Total Cats: 475
Default

Originally Posted by TravisR
They wern't ran in a car, but they are exact duplicates, we cmm'd another gear which reads down to .0001 as an additional precaution and we were provided files from the forum and they matched within thousands. A procedure like that would of added another month to the group buy atleast.

I also don't like the term "sell" perhaps passed along is the better term.

These are RC 16. Which is quite a bit higher then stock, but doesn't go into a dangerous RC that could wear the housing prematurely. For that reason durability should be extremely high. The originals did not go into the RC hardness range as I've been informed by loki.

We also spec'd the side to side clearance at .0033 in the 94-97 housing. I found my notes from the machinist. All the gears should be +/-.0005 of that.
Why make them any harder then the stock gears? The stock ones prove to last a long time, but being made of sintered steel, they are brittle and a few people that choose NOT to run a harmonic balancer broke them. (note nobody that runs a harmonic balancer breaks them in the first place...) Seems to me like simply making them from mild steel would get you a similar hardness as the stock gears or better, but they would be a lot stronger and less brittle then the sintered gears. Cheaper to buy stock, easier to machine, more durable. Win win win situation. I don't think making them any harder is doing us any favors, and only makes the gears more brittle, which is what we are trying to fix. Plus it's gonna cause more wear as the pump is cast aluminum, no? Why did you choose the material you choose to make them from?

Just me, but I would sure test my product before I started selling them. (or passing them along, you know what I mean) Sure, it might "seem" like they should be fine since they're an exact duplicate. But that doesn't mean much without testing. For all we know, the gears will shatter first time the engine spins 7K. I mean, you could have put them in an oil pump, put it on a engine, and put it on a dyno and load tested it or something. Would take a day to swap oil pumps, and another day to get the car on a dyno. At least some legitimate form of testing to make sure these gears are gonna work satisfactory. Seems like a good idea to me.

If it's not obvious, it looks like miataroadster requires you to send them an oil pump so they can machine it to some spec so that 1 oil pump gear will fit all pumps.
patsmx5 is offline  
Old 11-04-2008, 05:39 PM
  #203  
Elite Member
Thread Starter
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,850
Total Cats: 8
Default

Reason these are not tested is to keep cost down, I have no problem with that.
The only apparent problem is that the 01+ oil pumps are different and require different gears, that's all.
Zabac is offline  
Old 11-04-2008, 05:49 PM
  #204  
Elite Member
iTrader: (2)
 
BenR's Avatar
 
Join Date: Jun 2006
Location: ABQ, NM
Posts: 1,838
Total Cats: -7
Default

Originally Posted by patsmx5
(note nobody that runs a harmonic balancer breaks them in the first place...)


How many people actually have either the balancer or the gears, in the car and driving?
BenR is offline  
Old 11-04-2008, 05:55 PM
  #205  
Elite Member
iTrader: (16)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,292
Total Cats: 475
Default

Originally Posted by BenR
How many people actually have either the balancer or the gears, in the car and driving?
Most miatas came stock with oil pumps and a harmonic balancer. So I'd say a lot of people.

Zabac- I see your point. But this is an important part of the engine. It breaks, you're gonna loose a lot of money that you sunk into your engine. If this was say, a coil pack, and it broke, it might leave you stranded, but it wouldn't take out thousands of dollars worth of engine work with it. If I were sinking big money in a built engine, and doing so for RELIABILITY, I'd like to know all the parts I'm putting in are better than the ones I'm taking out. Not the other way around.
patsmx5 is offline  
Old 11-04-2008, 06:22 PM
  #206  
Elite Member
Thread Starter
iTrader: (39)
 
Zabac's Avatar
 
Join Date: Sep 2007
Location: High Point NC
Posts: 4,850
Total Cats: 8
Default

Understood, but we know (94-97 owners) that these are better then the ones we are pulling out, the issue as I see it lies only with the 01+ cars.
I just don't want anyone with the 94-97 oil pimp to panic for no reason.
Zabac is offline  
Old 11-04-2008, 06:54 PM
  #207  
Elite Member
iTrader: (3)
 
AbeFM's Avatar
 
Join Date: Aug 2006
Location: San Diego, CA
Posts: 3,047
Total Cats: 12
Default

Oh, no, you don't. And that's just Pat's point. How do you know it is better? Has your oil pump failed?

You have a at-least-one-works gear in the car. You're taking it out to put in a "has one EVER worked? no" gear in it's place.

Is that reason to scrap the whole idea out of hand? No. Would it be super awesome not to mention smart to try to do some testing on one before the first time someone revs to 5k or gets a hard knock the gear explodes?

Yeah, it would be good to know about that. These are a lot harder. Is it a problem? I dunno. Honestly I'm not familiar enough with the Rockwell scale to tell you if these are risky. I don't know if there's much to gain other than them not exploding.

The other bit of info I don't have: How many gears fail with the balancer on? I assumed the answer was "some" but I dunno.
AbeFM is offline  
Old 11-04-2008, 07:00 PM
  #208  
Elite Member
iTrader: (2)
 
BenR's Avatar
 
Join Date: Jun 2006
Location: ABQ, NM
Posts: 1,838
Total Cats: -7
Default

Originally Posted by patsmx5
Most miatas came stock with oil pumps and a harmonic balancer. So I'd say a lot of people.



You know what I mean.




In case you didn't, I was talking about the billet gears, and the ATI damper.
BenR is offline  
Old 11-04-2008, 07:06 PM
  #209  
Elite Member
iTrader: (16)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,292
Total Cats: 475
Default

Originally Posted by BenR
You know what I mean.




In case you didn't, I was talking about the billet gears, and the ATI damper.
So what's your point? I don't know how many people do that. Does that matter? It wasn't my point though. I'd say several hundred thousand have ran the stock oil pump and stock harmonic balancer. Broken OP gears is NOT a common problem. The few cases where engines HAVE broken oil pump gears have almost all been high HP engines that removed the factory harmonic balancer. It's pretty obvious that the balancer was put on the engine for a good reason. No surprise removing it can cause problems.
patsmx5 is offline  
Old 11-04-2008, 07:35 PM
  #210  
Elite Member
iTrader: (9)
 
TravisR's Avatar
 
Join Date: Jun 2008
Location: Houston, TX
Posts: 1,547
Total Cats: 13
Default

There are a couple of things we have to see here about all this hardness business. My material selection process was not unlike what any materials selection process undergoes.

I looked at the leading integral under the stress strain curves of the toughest steels commercially available. I then selected 4140 which was fairly priced and readily available, and very tough.

The next step was to evaluate the heat treating and if any was necessary. The hardness of processed material was available to two grades without further treating. One grade was RC 16 the other in RC 54. The stock gears were supposed to be somewhere in the area of RC 7-8. Rather than anneal the gears to stock specification I decided to keep them at their processed hardness. I then referenced an engineer I work alongside who has the better part of 35 years in engineering that runs engmanparts.com. If something I feel requires more experience then equations he’s the go to guy. He suggested to me through his experience that they would be fine at a slightly higher Rockwell as far as wear.

Given that I’ll visit toughness and resilience of modulus factors in predicting part durability. Toughness is the measure of energy any material would take until it fails. This measurement to at least some extent is independent of this value. It is very true that a hard material will facture rather than deform, it also true that there is a great amount of proportionality between the increase in resistance in deformation and the reduction of strain available.

The difference between these two different materials is not really their hardness. What the difference really is that a sintered material is just not as tough. That meaning that dp/dx on average is lower for the sintered gears.

Now how do I know that the gears will not shatter the first time they are spun up? I know two things.
The manufacturing process I chose is far superior to a sintered piece. A sintered piece is powder which is put under pressure and then heated to just below the liquidus marker. This results in poor crystalline structure and homogeny.

By contrast billet pieces are formed in a massive press under much higher pressures, and in such a way that is conducive to aligned and homogenous crystal structure. This reduces the dynamic flaws directly. In the milling process flaws are not created, so whatever the structure is that you see in forging that’s more than likely present in the end part.
Now given this knowledge how do we calculate that these are indeed stronger? Take energy and impart it on the stress strain curve and see if permanent deformation occurs. Looking at all the sintered steels there isn’t one that comes even close to 4140, and that assumes perfect manufacturing. So this is a no contest in that manner.

So I would say this, if these gears are in fact not even as good as the stock ones then there is only 2 explanations. One is that the metals are not properly formulated; the other is that the laws of physics simply do not work.

You know I’m working on my Ph.D. in Biophysics, I have 5 undergraduate degrees, and I’ve been doing engineering work for the last 5-6 years in very big rolls. I’ve been around this stuff for a while. You can sleep easy. What I can’t account for is when Mazda randomly decides to change the oil pumps, but as I have offered, I am willing to make the necessary changes to the part and keep everyone happy. Just relax guys you are in good hands, and I wouldn't have donated my time if I wasn't willing to work with you.

Last edited by TravisR; 11-05-2008 at 02:00 AM.
TravisR is offline  
Old 11-04-2008, 07:39 PM
  #211  
Elite Member
iTrader: (9)
 
TravisR's Avatar
 
Join Date: Jun 2008
Location: Houston, TX
Posts: 1,547
Total Cats: 13
Default

Yes, ship gears and pump housing back to me, I have to work it over with the machine shop still.
TravisR is offline  
Old 11-05-2008, 09:47 AM
  #212  
Elite Member
iTrader: (6)
 
Loki047's Avatar
 
Join Date: Sep 2005
Location: Chicago
Posts: 4,143
Total Cats: -5
Default

Originally Posted by TravisR
There are a couple of things we have to see here about all this hardness business. My material selection process was not unlike what any materials selection process undergoes.

I looked at the leading integral under the stress strain curves of the toughest steels commercially available. I then selected 4140 which was fairly priced and readily available, and very tough.

The next step was to evaluate the heat treating and if any was necessary. The hardness of processed material was available to two grades without further treating. One grade was RC 16 the other in RC 54. The stock gears were supposed to be somewhere in the area of RC 7-8. Rather than anneal the gears to stock specification I decided to keep them at their processed hardness. I then referenced an engineer I work alongside who has the better part of 35 years in engineering that runs engmanparts.com. If something I feel requires more experience then equations he’s the go to guy. He suggested to me through his experience that they would be fine at a slightly higher Rockwell as far as wear.

Given that I’ll visit toughness and resilience of modulus factors in predicting part durability. Toughness is the measure of energy any material would take until it fails. This measurement to at least some extent is independent of this value. It is very true that a hard material will facture rather than deform, it also true that there is a great amount of proportionality between the increase in resistance in deformation and the reduction of strain available.

The difference between these two different materials is not really their hardness. What the difference really is that a sintered material is just not as tough. That meaning that dp/dx on average is lower for the sintered gears.

Now how do I know that the gears will not shatter the first time they are spun up? I know two things.
The manufacturing process I chose is far superior to a sintered piece. A sintered piece is powder which is put under pressure and then heated to just below the liquidus marker. This results in poor crystalline structure and homogeny.

By contrast billet pieces are formed in a massive press under much higher pressures, and in such a way that is conducive to aligned and homogenous crystal structure. This reduces the dynamic flaws directly. In the milling process flaws are not created, so whatever the structure is that you see in forging that’s more than likely present in the end part.
Now given this knowledge how do we calculate that these are indeed stronger? Take energy and impart it on the stress strain curve and see if permanent deformation occurs. Looking at all the sintered steels there isn’t one that comes even close to 4140, and that assumes perfect manufacturing. So this is a no contest in that manner.

So I would say this, if these gears are in fact not even as good as the stock ones then there is only 2 explanations. One is that the metals are not properly formulated; the other is that the laws of physics simply do not work.

You know I’m working on my Ph.D. in Biophysics, I have 5 undergraduate degrees, and I’ve been doing engineering work for the last 5-6 years in very big rolls. I’ve been around this stuff for a while. You can sleep easy. What I can’t account for is when Mazda randomly decides to change the oil pumps, but as I have offered, I am willing to make the necessary changes to the part and keep everyone happy. Just relax guys you are in good hands, and I wouldn't have donated my time if I wasn't willing to work with you.
I am not worried at all about the material selection. I don't think it will be an issue, we are way above the stock gears in hardness and most likely less brittle.

When it comes to materials (especially metals) its 3% textbook 97% experience.
Loki047 is offline  
Old 11-05-2008, 11:18 AM
  #213  
Newb
 
mistersolo's Avatar
 
Join Date: Jun 2008
Location: Omaha, NE
Posts: 24
Total Cats: 0
Default

TravisR,

I purchased a set of the oilpump gears for my 01 motor. I was planning on doing an build in the future and I couldn't pass up the opportunity for billet gears at the group buy price.

I realize the gears probably won't work as they are, and I don't have a housing to send you because I'm currently using the 01 motor.

Are you planning on possibly having gears made specifically for the 01+ housings? I'm not really fond of machining the housing to fit the gears. Won't that reduce the volume of oil per revolution by 6 percent over the stock 01 gears and housing?

I'd like to just exchange the billet 94 gears for a set of 01 gears if possible.

Do you think there'll be enough demand for an 01+ specific gear set or should I return/sell my existing set?
mistersolo is offline  
Old 11-05-2008, 11:22 AM
  #214  
Elite Member
iTrader: (2)
 
BenR's Avatar
 
Join Date: Jun 2006
Location: ABQ, NM
Posts: 1,838
Total Cats: -7
Default

Originally Posted by patsmx5
So what's your point? I don't know how many people do that. Does that matter? It wasn't my point though. I'd say several hundred thousand have ran the stock oil pump and stock harmonic balancer. Broken OP gears is NOT a common problem. The few cases where engines HAVE broken oil pump gears have almost all been high HP engines that removed the factory harmonic balancer. It's pretty obvious that the balancer was put on the engine for a good reason. No surprise removing it can cause problems.



No need to get all defensive guy.


I'm wondering how necessary the gears, or the ATI damper are. If you're saying there has never been an oil pump gear failure in a car with a stock damper, I've gotta wonder why it's generally accepted that 8000rpm+ and 350hp+ on the stock damper kill the oil pump gears. I've never had one fail, but then I've never been over 350hp and 8000rpm at the same time with one of these motors.
BenR is offline  
Old 11-05-2008, 11:32 AM
  #215  
Elite Member
iTrader: (12)
 
JayL's Avatar
 
Join Date: May 2007
Location: Austin, TX
Posts: 1,881
Total Cats: 2
Default

Originally Posted by BenR
If you're saying there has never been an oil pump gear failure in a car with a stock damper, I've gotta wonder why it's generally accepted that 8000rpm+ and 350hp+ on the stock damper kill the oil pump gears.
There have been failures using the stock damper. It's just not very common because most people aren't anywhere near that power level. It also seems that most people are trying to take the proper precautions to prevent this from happening.
JayL is offline  
Old 11-05-2008, 12:31 PM
  #216  
Guest
iTrader: (6)
 
M-Tuned's Avatar
 
Join Date: Sep 2007
Location: Vaughan, On, Canada
Posts: 1,085
Total Cats: 1
Default

I personally broke 8 oil pumps on built balanced engines using stock pulley and gears. I even tried different builders and had this happen.
I was running 350+hp and 7700rpm. Any time I ran the RPM less than 7300rpm I would be fine. Problem is I made power till 8500rpm.

Just wanted to share my first hand info.
M-Tuned is offline  
Old 11-05-2008, 12:50 PM
  #217  
Elite Member
iTrader: (3)
 
AbeFM's Avatar
 
Join Date: Aug 2006
Location: San Diego, CA
Posts: 3,047
Total Cats: 12
Default

Originally Posted by Marc@M-Tuned.com
Just wanted to share my first hand info.
Thanks Marc, this is some useful info!!! Still it would be awesome to be able to test these. :-) It is hard to imagine them being worse though.
AbeFM is offline  
Old 11-05-2008, 01:10 PM
  #218  
Elite Member
iTrader: (16)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,292
Total Cats: 475
Default

Originally Posted by Marc@M-Tuned.com
I personally broke 8 oil pumps on built balanced engines using stock pulley and gears. I even tried different builders and had this happen.
I was running 350+hp and 7700rpm. Any time I ran the RPM less than 7300rpm I would be fine. Problem is I made power till 8500rpm.

Just wanted to share my first hand info.
Eight? Are you serious? How many engines did you build? Over what period of time? That sucks and is definitely a very unusual case. (IE-I doubt there are even eight cases of failed OP gears on engines with balancers not counting yours) And I'm gonna have to call you on "I made power till 8500rpm". It might have spun that fast, but no way on earth you were making peak power at 8500. Probably peak power around 7-7.5K tops.

99% of the built engines being built are gonna fall on their face at high revs just like every other miata engine. No need to spin the engine to 8K+. Sure, the over rev is nice, but other than that it's all those RPMs are good for.

Hard to imagine mazda would make different oil pumps for the same block. Hard to imagine they would change the oil pump on an 01. Hard to believe one guy broke 8 oil pumps. Hard to believe "billet" gears could break. (you know the factory gears are billet, right?) But that doesn't mean it isn't possible. I think the seller made too many assumptions and they catching up now one by one.

I think these gears are too hard for the application. I'm gonna laugh when someone puts these gears in their pump and breaks them. Who's gonna be the guinea pig to test these? Like Loki said, it's 3% text book, 97% experience. These gears might "seem" great (they're BILLET for crying out loud, they must be great! BILLET!). But the fact is nobody will know how durable these gears really are for a long time.
patsmx5 is offline  
Old 11-05-2008, 01:19 PM
  #219  
Elite Member
iTrader: (3)
 
AbeFM's Avatar
 
Join Date: Aug 2006
Location: San Diego, CA
Posts: 3,047
Total Cats: 12
Default

Good lord. Chill out. You raise a valid point that the gears are untested, and I for one would like to see someone push these, so I can feel better it's an upgrade and not a downgrade. I feel it is, but with some actual evidence, I would be more comfortable. I'm going to be running them.

The point of the post: Why even argue with what oil pump mazda put in in '01?? All it does it ruin your credibility. I posted pics and measurements for christ's sake. How do you expect someone to take you seriously when you're flying in the face of cold hard analytical reality? All the theory in the world won't change that I had two pumps side by side and they were different.

As to making power on the top end, there is likely something to be said for manifolds and cams and other tricks. I'd like to see a dyno plot, but while I might have my doubts on an untested dual feed rail, something which is testable and has been tested I won't discount out of hand if there's a chance to see some recorded results.

More useful would be to suggest how these gears might be tested, what you think will go wrong, etc.
AbeFM is offline  
Old 11-05-2008, 01:29 PM
  #220  
Elite Member
iTrader: (16)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 9,292
Total Cats: 475
Default

Originally Posted by AbeFM
Good lord. Chill out. You raise a valid point that the gears are untested, and I for one would like to see someone push these, so I can feel better it's an upgrade and not a downgrade. I feel it is, but with some actual evidence, I would be more comfortable. I'm going to be running them.

The point of the post: Why even argue with what oil pump mazda put in in '01?? All it does it ruin your credibility. I posted pics and measurements for christ's sake. How do you expect someone to take you seriously when you're flying in the face of cold hard analytical reality? All the theory in the world won't change that I had two pumps side by side and they were different.

As to making power on the top end, there is likely something to be said for manifolds and cams and other tricks. I'd like to see a dyno plot, but while I might have my doubts on an untested dual feed rail, something which is testable and has been tested I won't discount out of hand if there's a chance to see some recorded results.

More useful would be to suggest how these gears might be tested, what you think will go wrong, etc.
Reread my post Abe. I'm not saying your measurements are wrong.

I said "it's hard to believe....." about several things that are all hard to believe and accept, yet true. Wasn't saying Marc didn't break 8 OP's, or that you didn't measure two oil pumps, etc. Just trying to make a point that ASSUMPTIONS are poor things to make.

I have a crazy idea on how to test these gears. Install them in an engine. Run the engine. Run the engine hard and long. See how they hold up. But it's a little late now to start testing your product.
patsmx5 is offline  


Quick Reply: GB Billet Oilpump Gears



All times are GMT -4. The time now is 02:15 AM.