I run newer high grade bolts on the stock damper which are loctited in... The factory bolts should have been M8 sizing. My damper has the power steering / AC pulley lathed off so that it is a single 4-rib pulley. It's probably close to half the stock damper weight.

Running a billet oil pump and harmonic damper aren't bad recommendations, I'm just putting it out there that there is another different option that isn't as well known. As far as I know, the guys here running the Peterson valve aren't even using the billet oil pump gears. The external relief valve by itself is enough to stop shattering pump gears.I should point out that nearly all these cars are N/A not turbo'd, but most rev far far higher than 7400rpm. I also know that the billet gears were tested with stock dampers and there were multiple failures, so the billet gears alone aren't enough to stop the pump failures.

The external relief valves aren't overly expensive, and if you are already running an oil cooler then it's just the return feed into the sump that is tricky. It's also nice to be able to adjust oil pressure externally.

 

I am highly skeptical of this. I have pictures from the gears that came out of one of my motors that broke the a factory main bolt several years ago. 300+whp with no #1 main cap support, so the end of the crank was supported entirely by the oil pump. OEM damper too, since this was before the SPM damper existed. It fractured the oil pump housing in three places and cracked the #2 main cap as well. The billet gears were unscathed. In my experienced opinion, those gears are virtually indestructible.

 

This was told to me by a very reputable source so I don't doubt it. I'm not sure on the mechanics but I don't think the oil pump failure is caused by contact loading. It's something to do with the internal relief being overwhelmed or vibrations from the valve opening and closing causing the pump gear to blow apart. This failure occurs in high reving engines and may be different to a high power turbo build that sees more hp rather than revs.

 

Sorry, but I strongly doubt it. I would need to see pictures of the gears to convince me otherwise. My first-hand, direct personal experience indicates that the gears are indestructible.

 

That's fine, doubt away. I don't have photos and it's not my first-hand experience so I can hardly vouch for it. They weren't Boundary Engineering gears either as this would have been before their time, so they were probably custom made in Aus. It's not an easy thing to get experience with as the end result is a destroyed motor.

I have actually thought about buying a SuperMiata Damper, machining off the outer pulley and running it as a replacement to my stock one. It would fix my concerns with the two piece hub, although it might end up being too light to be effective.

 

I think you can already buy exactly that straight from BHJ dynamics.

 

OK, makes more sense now. Didn't mean to be a dick, but I know the torture I've put the Boundary billet gears through, and it's literally unfathomable to me that a set could shatter like the OEM gears. Like I said, I broke the housing first

Race Special Mazda MX-5 Miata BP Series 1.8 L 4-Cylinder Harmonic Damper [MAZ-IB1.8BP-6-SP] : BHJ Dynamics, Harmonic Dampers and Specialty Crankshaft Vibration Dampers. Butthole-puckering price, though

 

Just something that was pointed out to me while considering picking up the external valve. Pretty sure you need a non thermostatic sandwich plate, or you would get weird behavior on startup.

 

Unless I'm missing something, the thermostat just bypasses (most of) the cooler and loops the oil back into the filter. You could run the external valve pre or post cooler (smarter to run it post-cooler IMO, unless outlet pressure exceeds the max for your cooler core).

 

But if you are bypassing the cooler then you are bypassing the relief valve. Which would cause oil pressure control issues if its not open?

 

The external relief valve has to be first after the oil pump. I have never run a thermostat so I've never really thought about it but there are cars that do.

 

Ok. thats what I thought.

 

Only if you have the relief valve plumbed inline with the cooler.

 

this assumption was made a few posts back

 

So is there any more runs of these being made ??

 

Seconded...

 

Out of production until further notice. Too many production runs had to be reworked and parts scrapped because they did not meet the drawing or our quality standards. Simply put BHJ is just not able to make a consistent high quality product so we threw in the towel. We don't like the subject our customers to the inconveniences that come with parts that are not ready to install.

We are currently reviewing samples from other suppliers and have made a few design improvements along the way. No ETA or other information available at this time.

if you need a quality damper right now I would suggest the ATI from Flyin Miata. It's a bit more expensive but a proven piece.

 

Well ****. I have a used one that was sitting around, waiting to go on. How do I tell if mine is a P O S?

 

Its fine.

 

You won't know until your front main starts leaking :v