No BS: why do they blow engines all the time?

[Matt93SE]

Originally Posted by Lynxis

I should clarify that I'm not counting autocross which is a different beast in my opinion. But at the track, at least around here, Miata's have been declining since 2019 to the point that the last 3 track days I've attended had exactly 2 Miatas between all of them, both NDs if that matters to you. Not a single older model though.

A few ex-Miata guys I've spoken to about it mentioned they let the cars go because of financial pressure and the cars are getting too difficult to fix. It's my opinion that the pandemic has forced many people into making decisions about which vehicles to keep and 2nd vehicles like Miatas are the first to go while twins are often the owners only car. Factor in supply chain issues and manufacturers are just not producing parts for old cars anymore. My own 2008 Forester is unusable right now because it needs a new alternator tensioner that Subaru doesn't make anymore.

I expected my experience was spreading around because I don't think the situation here is special at all but perhaps not as much as I thought. Anecdotal experiences are hard to quantify like this.

I'm on the other side of the continent and results are completely different. Miatas are strong here in TX with SCCA Club racing. Spec Miata is large enough they get their own run group, and they are present in just about every small bore class they're allowed from Spec Miata to GT3. There are more Miatas entered on an average race weekend than any other car make/model combined. For example, we just had a race last weekend with a whopping 82 entries. 29 of them were Miata/ MX5 in multiple classes. I was the only 86 entered.

But as you say, there are certainly regional variations. Miatas in TX are strong because we don't have rust problems and 30 yr old cars are still plentiful. We also have many national champions and race shops here that specialize in them since they came out, so the chassis is well supported.
There are several tuners that support the 86 platform in TX, but there is only one race shop that actively supports them at the track (at this time.....)

[Lynxis]

Originally Posted by Matt93SE

I'm on the other side of the continent and results are completely different. Miatas are strong here in TX with SCCA Club racing. Spec Miata is large enough they get their own run group, and they are present in just about every small bore class they're allowed from Spec Miata to GT3. There are more Miatas entered on an average race weekend than any other car make/model combined. For example, we just had a race last weekend with a whopping 82 entries. 29 of them were Miata/ MX5 in multiple classes. I was the only 86 entered.

But as you say, there are certainly regional variations. Miatas in TX are strong because we don't have rust problems and 30 yr old cars are still plentiful. We also have many national champions and race shops here that specialize in them since they came out, so the chassis is well supported.
There are several tuners that support the 86 platform in TX, but there is only one race shop that actively supports them at the track (at this time.....)

Obviously prevalence is always going to be strongly region dependent. It stands to reason a place with nicer weather, a larger population and more relative wealth is going to have more Miatas. Older Miatas might have an easier time in a place like TX getting parts because there are still enough donors to get parts from but I recall Matt Farah talking with a guy from Flyin' Miata before or around the beginning of the pandemic and they were talking about issues getting parts for older cars.

I did want to make just one point about spec racing in general; I'd warn against using it to suggest the prevalence of track vehicles because it might seem bigger than it really is by virtue of it (mostly) being the same vehicles at all the events. I mean, if one looked at spec racing local to me a few years ago, one might think the most prevalent make/model of track going car would have been the Nissan Micra. No joke.

[Matt93SE]

Originally Posted by Lynxis

Obviously prevalence is always going to be strongly region dependent. It stands to reason a place with nicer weather, a larger population and more relative wealth is going to have more Miatas. Older Miatas might have an easier time in a place like TX getting parts because there are still enough donors to get parts from but I recall Matt Farah talking with a guy from Flyin' Miata before or around the beginning of the pandemic and they were talking about issues getting parts for older cars.

I did want to make just one point about spec racing in general; I'd warn against using it to suggest the prevalence of track vehicles because it might seem bigger than it really is by virtue of it (mostly) being the same vehicles at all the events. I mean, if one looked at spec racing local to me a few years ago, one might think the most prevalent make/model of track going car would have been the Nissan Micra. No joke.

Spec racing- an entry is an entry is an entry. If 35 of any car enter a race event in the weekend, there's 35 of those cars in attendance whether they're in a spec class or not.
and yes, parts are getting harder to find for the NA and NB Miata chassis, but the aftermarket is stepping up and the rules are evolving to allow aftermarket substitutions. for that example, they just updated the ruleset to run a spec Penske shock in the class over the Bilsteins they've been using for 20 years.

Spec Miata is also the most active class in the club, which is a hard number that cannot be discounted. 2022 cumulative totals are at 3157 total entries for the year so far, and 514 of those entries are in spec Miata, accounting for 16% of the total participation in the club.
https://www.scca.com/pages/majors-participation-2

In 2021, there were 5777 total race entries, 791 of which were SM (13.7%).
https://www.crbscca.com/staffAdmin/p...p?theYear=2021

Miata are also allowed in at least 10 other classes that I can think of off-hand, but the stats immediately available don't break down total participation by make. (I'm not going to spend 2hrs digging through race results and tabulating what I can see at the race track to make point on an interweb argument.)

The point is, while the FRS is becoming more popular, it's not going to replace the Miata in US based club racing anytime soon. There is still significant support and there will be for another decade. Maybe Subaru will have figured out how to build a boxer engine that doesn't have oiling problems by then.

[blsfrs]

Has anybody blown a 2nd gen engine yet? I'd be curious about oil analysis now that some folks have had them on the track a few times.

[CSG Mike]

Originally Posted by blsfrs

Has anybody blown a 2nd gen engine yet? I'd be curious about oil analysis now that some folks have had them on the track a few times.

I've seen a handful, but they were blatently abused. None reported that I know of under normal use, including track.

[ZDan]

We lost one (2015) at the track at Palmer MA the other day. FWIW *with* oil cooler. Driver says he's gonna get a new Subaru shortblock, they're available for $2k!

My opinion: FA20 is marginal on oil delivery to some of the rod bearings to begin with, and oil pressure falls off at high rpm (cavitation?). IMO maybe 1% of engines with machining tolerances at the "bad end" for oil delivery to critical bearings are just not gonna have a long life regardless of how well maintained. Maybe bump that up to 10% of engines that see a lot of track usage.

[Petah78]

Originally Posted by ZDan

We lost one at the track at Palmer MA the other day. FWIW *with* oil cooler. Driver says he's gonna get a new Subaru shortblock, they're available for $2k!

FA20 or FA24?

[ZDan]

Originally Posted by Petah78

FA20 or FA24?

2015 FA20

[Petah78]

I "think" i have read that the FA24 does not suffer from oil pressure issues even with high oil temp like the FA20 did. As such, i think they could be more reliable for track use?
However, please do not quote me as i can't recall where i read that.

[NoHaveMSG]

Originally Posted by ZDan

We lost one (2015) at the track at Palmer MA the other day. FWIW *with* oil cooler. Driver says he's gonna get a new Subaru shortblock, they're available for $2k!

My opinion: FA20 is marginal on oil delivery to some of the rod bearings to begin with, and oil pressure falls off at high rpm (cavitation?). IMO maybe 1% of engines with machining tolerances at the "bad end" for oil delivery to critical bearings are just not gonna have a long life regardless of how well maintained. Maybe bump that up to 10% of engines that see a lot of track usage.

It is almost always #2 or #3 rod bearing because the 3rd main feeds both those rods and the oiling hole is pretty much the same size as the 2nd and 4th mains. 2nd main feeds #1 rod only, 4th main feeds just #4. Before solidsnake11 got mad, threw the ball in the dirt and took his glove home, he had a thread with a bunch of posts detailing this. I believe he was slotting an oiling grove in the #3 main bearing to help get more oil to the rods. I can't remember exactly. I have some PM's from him on it but not all the detail.

We have upstream issues with oiling on the FA as well, pickup tube size and ect.

Edit: added corrections.

[NoHaveMSG]

Originally Posted by Petah78

I "think" i have read that the FA24 does not suffer from oil pressure issues even with high oil temp like the FA20 did. As such, i think they could be more reliable for track use?
However, please do not quote me as i can't recall where i read that.

It looks better but it's hard to say for certain. I have never gotten numbers anywhere near this at 200F oil temp on my car. my car also shows signs of pump cavitation above 5800rpm so My car is usually 40-50psi close to redline.

https://www.ft86club.com/forums/showthread.php?t=149512

[FrickingReallySlow]

Originally Posted by CSG Mike

I've seen a handful, but they were blatently abused. None reported that I know of under normal use, including track.

Mike you mean FA24 and not 2017+ shortblock right? was this during product development or testing the limits on a dyno? did they fail on the rod/bearing or did the failures look different from FA20

[blsfrs]

Originally Posted by NoHaveMSG

It looks better but it's hard to say for certain. I have never gotten numbers anywhere near this at 200F oil temp on my car. my car also shows signs of pump cavitation above 5800rpm so My car is usually 40-50psi close to redline.

https://www.ft86club.com/forums/showthread.php?t=149512

I don't know what Element Tuning does, but my OP is over 100psi when I'm over 4000rpm. When my engine was rebuilt after the rocker arm/timing chain disaster, my new engine guy didn't see anything unusual with the oil pump or other components except an aftermarket oil pick up tube. Per Element's instructions, I run Mobil 1 10w30.

[NoHaveMSG]

Originally Posted by blsfrs

I don't know what Element Tuning does, but my OP is over 100psi when I'm over 4000rpm. When my engine was rebuilt after the rocker arm/timing chain disaster, my new engine guy didn't see anything unusual with the oil pump or other components except an aftermarket oil pick up tube. Per Element's instructions, I run Mobil 1 10w30.

Damn, 100PSI !!!

Are you on an element block? I have my suspicions on a couple things they do. I need to figure something out before I start spinning 8k rpm.