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but I tend to stop for the night when I reach a question like this in the evening to sleep on it.
This hits super hard for me. Half the time I try to make a late night game time decision like that, I just come back the next day and undo whatever it is I was contemplating/trying to finish. Half the time, it's rolling the dice on some sort of ETA anyways. If Mountune hits you back tomorrow and tells you they'll be here by Friday, you're gonna be bummed if you've already resealed the oil pan.
I feel like the info must be on this site but baffles in general might not make a difference in oil pressure drops below "X" amount of g's, no? And/or say "X" amount of tire width/aero/weight? I mean for sure, overkill is better than underkill here. I put an upper baffle plate from Supermiata in my built BP, but I don't remember seeing any oil pressure drops on my original motor with 225s and mild aero.
This hits super hard for me. Half the time I try to make a late night game time decision like that, I just come back the next day and undo whatever it is I was contemplating/trying to finish. Half the time, it's rolling the dice on some sort of ETA anyways. If Mountune hits you back tomorrow and tells you they'll be here by Friday, you're gonna be bummed if you've already resealed the oil pan.
I feel like the info must be on this site but baffles in general might not make a difference in oil pressure drops below "X" amount of g's, no? And/or say "X" amount of tire width/aero/weight? I mean for sure, overkill is better than underkill here. I put an upper baffle plate from Supermiata in my built BP, but I don't remember seeing any oil pressure drops on my original motor with 225s and mild aero.
I was seeing pressure drops on my stock BP4W with stock pump and 205 section tires. By pressure drops I mean nose dives to the single digits on a hard braking zone and teens on some turns. Ignorance truly is bliss and that motor was still going when I yanked it. I've had no such issues with the supermiata baffle and Stage 2 pump with the VVT motor on stickier 225s. I can go find some logs if you would like.
T]I feel like the info must be on this site but baffles in general might not make a difference in oil pressure drops below "X" amount of g's, no? And/or say "X" amount of tire width/aero/weight? I mean for sure, overkill is better than underkill here. I put an upper baffle plate from Supermiata in my built BP, but I don't remember seeing any oil pressure drops on my original motor with 225s and mild aero.
I summarized my thoughts last summer in this post here, but I'll just go ahead and quote the most relevant part in another thread I linked there.
Originally Posted by emilio700
After building many engines here, most of which went into track cars, we can unequivocally say that oil pan baffles are a good thing. Looking at OP (Oil Pressure) data for various builds over the years, we see only minor oil pressure drops in long high G braking events. We see significant drops in oil pressure under sustained 1G+ cornering however. The engine in Vegas which saw 32psi and 420+whp at Super Lap last year didn't have a baffle. I simply forgot to tell our engine builder to install one. As a result, we saw scary pressure drops during sustained cornering, eventually leading to a spun rod bearing. In comparison, data from a similar engine with baffle plate running similar boost for much longer (w2w) sessions so virtually no lateral G relative pressure drops. To date, we have only lost two motors on track. One was a severely lightened crank spun at 8500 rpm that lost a main bearing. The other was Vegas motor run without a baffle, data showing exactly what killed it.
There are a few good baffle plates on the market. An experienced engine builder can easily make one from sheet steel. We offer the Mazda piece on our site, which needs minor trimming to fit the BP sump. The Maruha also works and I'm guessing there are others. The OEM baffle is too small to work at sustained high G's. You may wonder how Spec Miata engines survive. The answer is they don't. The fastest specs in the country run expensive 0W20 1~1.5qts low, all in the quest for 130whp through the stock airbox, restrictor, manifold and ECU.
The front running SM engines make that power for 5-15hrs, not 100+hrs like most of you expect from your BP's.
Supermiata says they get them from Mazda, and Mazda says they source them from JPM. So those should all be the same, and while it's executed differently and made out of aluminum, the Sagespeed unit I have should function just as good.
I'm a bit surprised I don't see any different style of baffle out there that extends these 45* baffles out. It would require quite a bit of fiddling to get around the pickup, so maybe there's my answer.
Originally Posted by redursidae
I was seeing pressure drops on my stock BP4W with stock pump and 205 section tires. By pressure drops I mean nose dives to the single digits on a hard braking zone and teens on some turns. Ignorance truly is bliss and that motor was still going when I yanked it. I've had no such issues with the supermiata baffle and Stage 2 pump with the VVT motor on stickier 225s. I can go find some logs if you would like.
This pretty much matches my experience on grip level, pressure dips, and engine life. My original engine was worn out when it was removed, but the bearings weren't the issue. 200k miles and 35+ track days isn't a bad run. While having the vertical wall baffle installed with the horizontal plate was belt and suspenders, I should still be comfortably benefitting from the 80:20 rule. If it's good enough for 1.5g cars, it should be good enough for me and my full interior. I spent some time studying the baffle options instead of assembling the engine, but I think it was time well spent.
Last edited by OptionXIII; Apr 20, 2026 at 09:16 PM.
I sealed up the oil pan on Tuesday. Last night before installing the engine, I test fit the spare JDM 6 speed I have laying around to confirm the clutch plate was centered. While it was connected, I tested the spare starter it came with and used that to prime the system until oil came out of the filter housing.
Doing an engine install twice in two months definitely helps speed things along. I'm still far from @Z_WAAAAAZ work pace though.
There's still plenty to do to button it up - radiator install and coolant fill, rear brake pads, hood, etc etc. But I'm hoping to be driving it by the weekend.
I got it out in time for dinner, actually. It's amazing how much less time it takes once you do it once, and when you learn what the factory did that you don't really have to do.
The engine pulls... Good? It's a BP. It moves the car. It has good oil pressure, no VVT clatter on startup like my old engine, idles quieter, the crankcase pulls a vacuum while idling too, and seems to have most of the factory horsies still in the stable.
Do I sign up for a Track Night in America next week without redoing the timing belt and water pump? 😂
I heard a great interview of Les Claypool by Nick Beato recently. Lots of history with other bands I was unaware of. He went to high school with people from Green Day and a bunch of other bands. Really fun to hijack your thread with this, lol.