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NB fuel pressure is 60 psi, but is not manifold referenced because the regulator is in the fuel tank. So as boost goes up, the effective flow rate of the injectors drops, meaning you need to be careful with rules of thumb about how much injector you need for how much power
But then you throw 10psi of boost into the engine.
With an NA and its manifold referenced 1:1 pressure regulator and 43.5psi (3 bar) base pressure, the fuel pressure rises at the same rate as boost. So by the time you hit 10psi in the manifold, your rail pressure is now 53.5psi but the injectors stay at a constant 425cc/min.
With an NB with is 58psi (4 bar) base pressure and NON manifold referenced regulator, your pressure actually drops at the same rate that boost increases. 58psi (4 bar) base pressure + 10psi of boost = injectors see 48psi fuel pressure. This means that at 10psi of boost, your 490.75cc/min injectors are now 446.44cc/min
But that's ok! Because you still have plenty of headroom for 200hp at that pressure.
Notice that says "(Static flow) injector required @ test PSI 43.5"
As long as you keep pressures in check and understand the relationship between boost pressure, supply pressure and injector flow rate, you should be fine. This was all calculated at a (probably) conservative 80% DC and 0.65 BSFC so you definitely have some headroom.
Spend some time playing with it and you'll learn all kinds of cool stuff
Originally Posted by Steve Dallas
I checked all the quick and obvious things, with regard to the oil consumption. The only potential cause I found, is a PCV valve that does not rattle as freely as it should. There was more oil in the hose than I'm used to seeing, so hopefully it is as simple as that.
The BP tends to make a lot of windage inside the block due to the oil squirters constantly blasting the bottoms of the pistons with oil. When we start tracking these things and running them at high RPM for extended periods of time, the stock PCV system tends to get overwhelmed. This is why you see so many threads with elaborate catch can setups and ginormous -10AN fittings welded to their valve covers. In my opinion, at a minimum, you should consider some sort of basic catch can setup if the car is going to see track time. The last thing you need is all that oil vapor going into the engine. It reduces the octane rating of the fuel, and that's not something you want at the track.
Originally Posted by Steve Dallas
Otherwise, the 5W30 synthetic I am using may be too light for track work. I will change the oil and inspect it for any oddities, and probably send a sample to Blackstone for analysis out of an abundance of caution.
What specific 5W30 synthetic are you using? The NB is crippled in that it has a fake oil pressure gauge and no oil temp, so its going to be difficult to quantify oil things, but I'll share some of my experience.
Back when my NB was stock (AC/PS, etc) I would see oil temperatures excess of 240°F on the highway. From what I understand that's a bit on the high side, and that's just highway usage. One particular incident I remember quite vividly before I added aftermarket gauges for pressure and temp, I'd pulled off the highway to get dinner or lunch or something after a several hour long run up I5 in NorCal heat, and my engine was rattling like crazy. After leaving the car parked for an hour, I started it up and it sounded fine. As soon as I had arrived at my destination, the death rattle had come back. The next morning, rattle was gone. After some research I came upon the some data about the 5W20 Mobile1 (that M.net was telling everyone to run at the time) was garbage at super high temps, and my oil was probably shearing down like crazy to probably a 5 or 10 weight. No Bueno. Disassembly of my motor some time later showed contact scuffing on the bearings, and I attribute that to the above incident.
I've read people are seeing as high as 260-270°F on stock motors at the track, so I would imagine yours are as high, if not higher. We all used to recommend Shell Rotella T6 5w40 (before it was reformulated) because it was one of the only things that would not shear down at super high temp, and it was $20/gal at the walmart. Getting a Blackstone analysis of your CURRENT oil after your track day will definitely let you know how badly the oil was abused, or how far its sheared down from its initial advertised viscosity, or if its full of bearing material :( You may wish to consider something slightly more exotic than an off the shelf synthetic, and you may want to go to a heavier weight to maintain viscosity at temp. Andrew @ Trackspeed Engineering would be a good person to call and talk to about oil. He's an Amsoil dealer and a Miata guy so he can get you pointed in the right direction as far as oil goes.
With the turbo I'm now seeing 270°F+ at the track, and about the only thing that is going to work for me at these temps is 15W50 Amsoil Dominator (or one of the heavier grades of Royal Purple) but I know I'm right at the limit of common sense. I'm abusing my oil so I change it before every track day. Its expensive, but then so was my motor. For me, an oil cooler is no longer a good idea, its pretty much a requirement.
I hope some of this rambling will help. I'm no expert, but I'm happy to share my limited experiences.
But then you throw 10psi of boost into the engine.
With an NA and its manifold referenced 1:1 pressure regulator and 43.5psi (3 bar) base pressure, the fuel pressure rises at the same rate as boost. So by the time you hit 10psi in the manifold, your rail pressure is now 53.5psi but the injectors stay at a constant 425cc/min.
With an NB with is 58psi (4 bar) base pressure and NON manifold referenced regulator, your pressure actually drops at the same rate that boost increases. 58psi (4 bar) base pressure + 10psi of boost = injectors see 48psi fuel pressure. This means that at 10psi of boost, your 490.75cc/min injectors are now 446.44cc/min
But that's ok! Because you still have plenty of headroom for 200hp at that pressure.
Notice that says "(Static flow) injector required @ test PSI 43.5"
As long as you keep pressures in check and understand the relationship between boost pressure, supply pressure and injector flow rate, you should be fine. This was all calculated at a (probably) conservative 80% DC and 0.65 BSFC so you definitely have some headroom.
Spend some time playing with it and you'll learn all kinds of cool stuff
Thank you for the lesson. That all makes sense. Just when I thought I knew what I was doing! I was calculating for the 1:1 ratio. Damn NB weirdness!
So, if I am shooting for 230BHP to account for drivetrain loss and end up at 200WHP, I actually need injectors that flow at ~467cc at 48.5psi to be perfectly safe and by the book. That means my yellows may be a little small for my purposes. I also have a set of brown secondary injectors from a 2010 RX-8 on hand. Their flow rate has not been easy to find, but I'll keep digging. I know they flow more than yellows, but I don't know how much.
Originally Posted by EO2K
The BP tends to make a lot of windage inside the block due to the oil squirters constantly blasting the bottoms of the pistons with oil. When we start tracking these things and running them at high RPM for extended periods of time, the stock PCV system tends to get overwhelmed. This is why you see so many threads with elaborate catch can setups and ginormous -10AN fittings welded to their valve covers. In my opinion, at a minimum, you should consider some sort of basic catch can setup if the car is going to see track time. The last thing you need is all that oil vapor going into the engine. It reduces the octane rating of the fuel, and that's not something you want at the track.
A catch can is on my TODO list. I will move it up in priority. In all honesty, I have probably placed too much faith in what the local Spec Miata racers do. More on that in a minute.
Originally Posted by EO2K
What specific 5W30 synthetic are you using? The NB is crippled in that it has a fake oil pressure gauge and no oil temp, so its going to be difficult to quantify oil things, but I'll share some of my experience.
Well... Since you asked... I use Valvoline Synpower 5W30 in my Tacoma (230K miles), and I happen to have several jugs of it in the garage. So, that's what I poured in, thinking it shouldn't matter much, since I'm still N/A, I exchange the oil every 3 track days anyway, and it hasn't been more than 80F out there yet. This obviously deserves much more consideration.
Originally Posted by EO2K
Back when my NB was stock (AC/PS, etc) I would see oil temperatures excess of 240°F on the highway. From what I understand that's a bit on the high side, and that's just highway usage. One particular incident I remember quite vividly before I added aftermarket gauges for pressure and temp, I'd pulled off the highway to get dinner or lunch or something after a several hour long run up I5 in NorCal heat, and my engine was rattling like crazy. After leaving the car parked for an hour, I started it up and it sounded fine. As soon as I had arrived at my destination, the death rattle had come back. The next morning, rattle was gone. After some research I came upon the some data about the 5W20 Mobile1 (that M.net was telling everyone to run at the time) was garbage at super high temps, and my oil was probably shearing down like crazy to probably a 5 or 10 weight. No Bueno. Disassembly of my motor some time later showed contact scuffing on the bearings, and I attribute that to the above incident.
I've read people are seeing as high as 260-270°F on stock motors at the track, so I would imagine yours are as high, if not higher. We all used to recommend Shell Rotella T6 5w40 (before it was reformulated) because it was one of the only things that would not shear down at super high temp, and it was $20/gal at the walmart. Getting a Blackstone analysis of your CURRENT oil after your track day will definitely let you know how badly the oil was abused, or how far its sheared down from its initial advertised viscosity, or if its full of bearing material :( You may wish to consider something slightly more exotic than an off the shelf synthetic, and you may want to go to a heavier weight to maintain viscosity at temp. Andrew @ Trackspeed Engineering would be a good person to call and talk to about oil. He's an Amsoil dealer and a Miata guy so he can get you pointed in the right direction as far as oil goes.
M.net. That's where we go to sell our used junk, right?
I exchanged the oil last night with Mobil 1 0W40 and drove the car to work this morning. I was not able to recreate the rattling sound with the higher viscosity oil, so this may be the same thing. Good news / bad news. :/
I did take a sample of my old oil for analysis. There was no metal on my paper towel drain "filter" and no traces of water/coolant, so those are good signs. I'll post Blackstone's results, when I get the report.
That Rotella 5W40 is very popular in the rotary world--even after the reformulation. People who do not have cats are still running it successfully. Blackstone reports on other oils have created a consensus that Mobil 1 0W40 is next in line for shear resistance, and I have had very good luck with it in my RX-8, which is absolutely brutal on oil on the track. Designer oils like Amsoil are always on the table, but it would be nice to be able to continue to buy oil, bullets, and beer at Wally World.
Originally Posted by EO2K
With the turbo I'm now seeing 270°F+ at the track, and about the only thing that is going to work for me at these temps is 15W50 Amsoil Dominator (or one of the heavier grades of Royal Purple) but I know I'm right at the limit of common sense. I'm abusing my oil so I change it before every track day. Its expensive, but then so was my motor. For me, an oil cooler is no longer a good idea, its pretty much a requirement.
I hope some of this rambling will help. I'm no expert, but I'm happy to share my limited experiences.
The Spec Miata guys I have spoken with like to use the lightest oil that will maintain pressure (to reduce frictional loss), and use as little of it as possible (to prevent frothing). I see a lot of various brands of 0W20 and 5W20 in use, and they tend to fill it only to the bottom of the dipstick. I realize that's a totally different ballgame, and don't plan to take that advice, but I do find it to be an interesting approach. But, given that information, I kinda figured 5W30 would be OK--at least in cooler weather.
An oil cooler is also on the TODO list. I have most of the parts on hand, but I'm stuck in analysis paralysis over its location. The realist in me knows I should just yank the A/C and copy Hornetball with a big cooler right behind the radiator, but the sissy in me sure loves pointing the car toward home, setting the cruise control, turning on the A/C, cranking up the radio, and zoning out for 2 hours after 8 long hours of driving and instructing on a hot, humid track day. Anyway, this just moved up on my priority list as well.
Thanks for taking the time to share your experience. It is very much appreciated.
.
Last edited by Steve Dallas; May 19, 2017 at 02:04 PM.
I finally got around to doing a compression test, and the engine passed with flying colors. A friend of mine has a leak-down tester, and he helped me do that for the first time. Also passed that test. All good so far. Just awaiting the results from Blackstone, but I am mostly convinced this is a mechanical rattle that is not related to the drivetrain.
While replacing the PCV valve and grommet, I went ahead and installed a used catch can that I picked up from a member here.
To Do List
Brake ducting
Use wire ties for something
Brake lines
Oil cooler before spring (have parts)
Coolant re-route before spring (have parts)
Remove pesky little coolant lines
Make environmentalists cry
Radiator sealing and ducting before summer
Oil and water temp gauges before summer
Seats and harnesses
Clutch (have parts)
Learn to drive (hopeless endeavor)
ECU
Match spec Miata record (never gonna happen)
Trubo!
I seem to be behind on that sorta important stuff I was planning to do before spring. Should probably get around to doing those things. Good thing this has been an unusually mild spring, and the ambient temp has topped out at 80F on track days so far.
Looking to build a fast-spooling, low-boost, track-reliable setup for about 200WHP. Was thinking of buying a FMII setup, with all reliability upgrades, without electronics. Assuming the manifold is track-worthy, and my #searchnewb seems to indicate that it is, why wouldn't this get me where I want to be for less $$ and more awesome?
That comes with the best manifold, the best turbo, and the best oil/water lines available anywhere at any price. It is brand new and proven.
That other little setup is a very nice setup, but there's no way I'd pay $2500 for it. This is also the same reason I'm still running my setup -- its value plummeted once TSE finished their kit.
I hear what you are saying, believe me. The TSE kit is undeniably the best available.
I don't want to be that annoying newb, who asks for expert advice, then argues against all of it. But, I do have some budget and time constraints on this build, and I can't afford to let the perfect become the enemy of the good. (As long as we're riding ****-ches, "If it's worth doin', It's worth doin' right!") I also have to be able to pass emissions every year, and want that to be as easy as possible.
I started putting together a spreadsheet of TSE vs. track-worthy FM, and the TSE setup got expensive quickly with all the needed extra bits and shipping for all of that stuff. Financially, I can do the used kit or an FM kit now, or save for another year. I am also about to start building a house, which means having to sell mine and rent for several months, which likely means no garage, which means next summer on that too.
Maybe I should finish that spreadsheet and post it for forum review. It might be an exercise that is beneficial for many people. Maybe?
I can PM you about what I spent for my various turbo bitz. I ended up with a full FM setup from manifold back (2.5 exhaust), MS3X, Mustang injectors with the FF adapters, AEM wideband, Vibrant intercooler, and 2 inch piping. I think I ended up in the realm of 3200-3500 for all the turbo related stuff.
I can PM you about what I spent for my various turbo bitz. I ended up with a full FM setup from manifold back (2.5 exhaust), MS3X, Mustang injectors with the FF adapters, AEM wideband, Vibrant intercooler, and 2 inch piping. I think I ended up in the realm of 3200-3500 for all the turbo related stuff.
Yeah, but yours isn't finished. It has to be finished to be track-worthy. That means cooling, heat shields, allthethings.
Yeah, but yours isn't finished. It has to be finished to be track-worthy. That means cooling, heat shields, allthethings.
I have a reroute waiting to go in.
Have the trans tunnel shielding that sixshooter recommended.
Have an oil cooler waiting to go in.
Just needs to get hood vents tbh.
I've been too lazy to install the undertray (have to cut it up for the piping) and I still haven't had any heat issues yet with crippled radiator flow.
All that said, 10 mins on the track puts more stress on your ish than a 4 hr drive does on mine from what I know, so....
Guessing you'd have to have a catch can setup, brake ducting, etc. Right?
I have a reroute waiting to go in.
Have the trans tunnel shielding that sixshooter recommended.
Have an oil cooler waiting to go in.
Just needs to get hood vents tbh.
You did the trubo, before you did the reliability stuff? No wonder the vets give you such a hard time! Your enthusiasm is understandable, but your planning may need some work...
Originally Posted by ridethecliche
I've been too lazy to install the undertray (have to cut it up for the piping) and I still haven't had any heat issues yet with crippled radiator flow.
All that said, 10 mins on the track puts more stress on your ish than a 4 hr drive does on mine from what I know, so....
The Koyo radiator is JUST. THAT. AWESOME. Not really. You need to get around to the sealing and ducting part sooner rather than later.
As an aside, I have not seen my coolant temp rise above 205F on the track yet, although ambient temps have stayed below 85F so far this year.
Originally Posted by ridethecliche
Guessing you'd have to have a catch can setup, brake ducting, etc. Right?
I have had brake ducting since the beginning. A catch can went on last weekend (look toward the top of this page). Something about reading more and posting less rings a bell, but I can't put my finger on it... :P
Originally Posted by ridethecliche
Get an MS, run it NA for a bit and go from there!
Always in the back of my mind. The MS plus wideband will be my next purchases. Maxing out N/A performance will give me a chance to learn to tune, and who knows? I may net enough ponies for my butt dyno to actually feel something for realsies. I have given real thought to installing the typical bolt-on "power" mods, tuning for them, and letting it ride for another season.
.
Last edited by Steve Dallas; May 31, 2017 at 01:18 PM.
Right, I'm using the car as a DD, so it sees boost when I feel like it. If this was a track car, then doing everything as you suggested in that order would be the way to go.
I had a few minutes to kick this around again last night, and this is where it stands now. I know I am forgetting a few things. I also know there are ways to do things cheaper (eBay intercooler and DIY intake hoses, etc.), but some solutions are too elegant to not implement.
The two kits are not as far apart as I remembered, although the difference does technically put the TSE kit outside my $5,000 budget.
EFR also has EBC built in with the one from TSE I think. I also trust the TSE inconel studs far more then the FM studs. TSE has shown lap times sub spec-miata with no stretching, while FM has not.
EFR also has EBC built in with the one from TSE I think. I also trust the TSE inconel studs far more then the FM studs. TSE has shown lap times sub spec-miata with no stretching, while FM has not.
I've done plenty of sub-spec miata laps @ Laguna on FM's inconel studs, they work fine.
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