94-00 gasket, no other mods. Engine runs too cool so, no problems. We'll run a fairly fine mesh rad protector screen at Thunderhill to cut aero drag and keep clt temps near 195°

silly question really, but is there a reason you picked 195*? Are you guys running an oil cooler btw (and which one if you are)?

that's the optimal operating temperature.

optimal for longevity I assume? I am just trying to understand why 195 as opposed to any other value, like say 180, or 205?

With my current cooling, I am running at 190-195 on track. We will find out what I end up at when it gets cooler since my Tstat is 180.

195° works for us. Setrab, -10 Aeroquip socketless

My Aeroquip socketless blue hose leaked after about 1-year, through the ply.

We have been using it for many years without issue. We'll keep an eye on it though. Thanks for the heads up.

Hmm, temperature controlled radiator louvers anyone?
Which also close partially at high speeds?
When the temps are low they're shut, to reduce drag...

Prop airplanes have been doing this for decades.
And now the GM Cruze does it too...

I've read an engine's wear rate is dramatically higher when it is warming up/under optimal temps vs high revving at optimal temp.

Yep, and ecomodders have been doing it for a while now. They run the ECT and AFR hotter for more MPG.

Movable aero = points. We thought of that. We can not modify the front bumper skin without taking points either. Rad protector screens are free and the rules do not state what open % or how they are fitted. So we fit it flush with a low open %, just like NASCAR and for the same reasons.

Is a adjustable radiator screen considered "Movable aero"?
I'm thinking about a cable operated screen ("Radiator Curtain shutter" seems to be one term, precursor to the thermostat).
It would in principle be a adjustable aero, but maybe not in the rule book. :)

It would actually be moveable aero and bumper skin modification. Fine mesh screen is the simple solution and achieves our goals. Besides it's not like teh temp swings 60° in one race. We can uses different screens based on checking temps in practice. Not a big deal.

hmmm would running the radiator fan backwards achieve a similar result?

Fan running backward wouldn't reduce aero drag significantly nor protect oil cooler and rad from Honda connecting rod bolt heads. It's not just solving a problem, but trying to maybe solve a few problems with one mod, in the simplest way possible. Eliminate redundancies. Emilio likes elegant engineering solutions.

You guys are funny. Presented with the same problems we were, your gearhead minds all go into overdrive trying to out think the competition and stay legal like we did all year. That aspect is one of my favorite things about racing, particularly enduros. Lots to think about, ideas to try.

If said shutters are behind the radiator, does that count as "aero"?

No, but that doesn't do much to protect the radiator and is far more complex, difficult to implement, test and service than a screen.

Cars from any sanctioning body can run NASA enduro. There only 4 classes for production based cars, ES, E1, E2 and E3. Cars from other series are "mapped" into their respective endurance class. We are mapped in from NASA's own Performance Touring series as a PTD car. So those are the rules we work within as well as the enduro supplement and T25 specific stuff.

Current versions of the NASA rules. They get updated without warning and sometimes randomly so it pays to know where all the latest versions are hosted and check them frequently.

2011 NASA enduro rules
2011 NASA Thunderhill 25 hours supplement
2011 NASA Club Codes and regulations
2011 NASA Performance Touring rules

Knock yourself out.

The Focus does that as well. It would be possible to do with MS3. I'd also set up a condition that kept the shutter(s) open at high speed if coolant > X°. But as Emilio said, not possible with his classing.

Most of the enduro cars I see have a simple, small high flow fan tied to the radiator. No fancy control. No fancy behind radiator shroud. Just a little ducting.

I usually find the race car engineering more fascinating than the race itself.

Well you could have the screen to protect the rad *and* the shutters to improve aero. ;)

Yup. We're using a single 10" Derale fan, no shroud. Set to come on at 200° clt. The Derale weighs about half the stock fan. We have found that the shrouds on Miatas reduce the airflow substantially when the fans are off. The shrouds are good band-aid when you have inadequate ducting. So we just seal off everything to make sure it's all going through the core. The undertray helps a bunch by reducing pressure behind the rad so the differential across the core is good anytime the car is moving. We have yet to see the fans turn on when the car is moving even racing in 90° heat.

OK, we'll build it just for you.

So with the screen is doing it's job reducing aero lift/drag while protecting the radiator and reducing airflow to the required amount for a given event during practice, how would one tune the shutters knowing that the car will overheat unless they are full open?


edit:
It's really easy to get caught up doing stuff just because it sounds cool while losing sight of the bigger picture. In our case, even of the shutters were a free mod, weighed nothing, zero cost, 100% reliable, 1 minute to install.. we would still not do it because we still need a screen and it does both jobs. In race engineering, one has to sometimes pull their ego out of the equation. As a guy with a substantial ego, I have been reminded of this constantly when developing Crusher. You Jason, like to question everyone else assumptions and solutions. It's your raison d' etre and the right frame of mind when building a system. You're also an engineer and suffer from, well, thinking too much.

Cooler ambients perhaps?

Or use a less restrictive screen and close the shutters some at very high speed where the aero matters most?

:)

Tell you what, you build an enduro car with shutters and we'll see which solution works best.

Hey, I'm just throwing out food for thought for everyone, I'm not saying you should do it! :)

one thing to remember is - December at Thunderhill is most likely going to be 20F-50F

true. but that don't apply to race car as much.

for a street car, it is started up cold a minimum of 14 times a week (going and leaving work), 700 times a year.
for a race car, it is started up cold may be 30 times a year tops (that would be a lot, average racer races 10 days a year). imo, for a race car, most wear happens at high revving at optimal temp.

50*F? You wish. :giggle:

The last time I did a Thunderhill event in December:

-The car, which sat on an open trailer all night, was frosted over from front to back. The low was ~25*F IIRC.
-I tried pouring a cup of water on the windshield to de-ice it - this is known as a "terrible idea" to anyone from the east coast, but in California it's how we defrost windshields. Apparently Thunderhill is on the east coast, because the water I poured onto the windshield IMMEDIATELY froze.
-The driver's side door lock had nearly seized - luckily the passenger side worked, but it still took some effort to unlock the door from the inside.
-We arrived at the track at 7:30am - the trunk would not open until shortly before 9am (frozen shut).
-I have a photo of the car sitting on pit lane, waiting for its first session, with ice on both sides of the windshield left over from the ice scraper.

Now you're just getting technical lol and I was just giving input to "Track's" question. I'd pick 195 if you can keep it there, I've read somewhere where it will wear less at 195 than 180. I have mine at 180 w/ 180tstat since I don't have a reroute yet, and the supposed drawback of a re-route-less setup is Cyl 3 and 4 run 20* hotter.

For 24h race when the ambient temps change you always have the pit stops where the team can change small things.
Tearoffs and other simple stuff (strips of tape to add/remove) works, servo motors and delicate mechanics don't :)
Even a simple cable pulling on a spring loaded shutter can jam when you really want it to work.

I don't have a reroute, and my car runs 190-195* on track. I am pretty sure this setup is working optimally for my setup. But I am more curious about how people determine 180 over 195? Its not like there is a magical meter which tells you wear. But yea, I picked the 180* because with the stock one, I was sticking around 205-210, so I figured dropping it some to assist my oil would be good until I get an oil cooler.

Never really anticipated the coil months, but no big deal, i can seal off part of the radiator if it runs reallly cold at RA. Doubtful though.

aka K.I.S.S.

:)

Hey what do light plane shutters look like? They need to be reliable and freeze proof, right?

Questions for u engineers ? Most of the teams are from socal. We don't know what snow look like. Are there any particular issue with low temp on car parts ? Will regular wiper be enough ? Will say any parts become brittle ?

I'm only a software engineer, but have lived in reasonably cold regions. To change my DD from "summer" to "winter" mode, I change the tires and make sure I have 0* washer fluid. That's it, and is sufficient down to about -10* where gearbox fluid is a bit stiff first thing in the morning.

For racing, I would consider tire choice carefully considering the temperatures.

Plastics are a bit more brittle when working with them, but I generally try to avoid working with them in the cold. Working with 28 y/o plastics in my MB is just as much of a pain. If you have the option of a mostly enclosed (3-4 sided) work area, get a heater of some sort for both your sake and the parts.

i would say about the only thing would be to get premium wiper blades rated for cold climates. oh yeah, and sorry jason, but gotta say what everybody's thinkin' "fuck yo shuttas fool!"

:facepalm::facepalm::facepalm:

There is some stuff, not sure if its sold in cali *shrug* who knows. called window de-icer. they make it in spray cans, great for opening doors that are frozen shut, and for your windshield washer bottle, it'll get any ice off. I haven't used it much myself, so you may want to try it before committing to it, ie see if it smears on the window. what not.

But its certainly a good idea to try

just dont put HOT water on the windshield. or as they say "your future former windshield"

Lexan

in that case you can consider it the removal process.

Windshield is quick release already. Car also has monster custom built defroster. Pretty sure we won't have issues with windshield frosting.

More details on defroster? I'm still looking into option to make my gutted car driveable in rainy/winter conditions.

The OEM heating unit is enough to melt the ice off of my REAR window in the dead of winter, when it was around -15C...I don't think a huge one is too necessary.

OEM heater core removed from housing. 6" or so Derale fan, small fabricated sheet aluminum box, OEM dash ducting. Fan is a bit overkill but it blows a fogged windshield dry in about 20 seconds at 80 mph. That its also about 85db goes relatively unnoticed in a 100db interior.
Whole thing weighs maybe 4lbs. Nuclear defroster.
https://www.miataturbo.net/attachmen...ine=1320804684
https://www.miataturbo.net/attachmen...ine=1320804684

We need to think about the windshield washer system, as well. If it rains enough to get the track wet (and hence muddy, since most cars don't have driver selectable ABS!) but not enough to keep the windshield clean, clear vision becomes a struggle against the constantly-muddied-windshield from spray from other cars as we zoom past them. Having to do an extra pit stop to refill washer fluid would be a bummer.

Cheers,

Dean

Gotcha. I was hoping some fancy CF ducting and vents. I hate setting stuff up onder the dash, especially since all the OEM vents etc. are gone.

Good idea. Yet another thing on the list for John. Probably run some alcohol or anti-freeze as well to keep it liquid. Probably fit a really big tank so we don't have to refill it every stop if the track gets ugly.

We have no heater, just a defroster. So all of the system's substantial heat is aimed at the windshield only. That is exactly what we want for what we are doing.

If you are referring to what might be necessary for a track day or street car, maybe so.

Text in mirror: "Objects in mirror are losing"

Read aloud in Italian accent: "Whats ina da rear view mirra doesn'ta matta!"

Uh, unless that thing in the mirror is an approaching LMP-1 car, and rumors have more than one showing up to do this race! All cars running amber lights SHOULD be at least 10 seconds a lap faster than us. Many won't be, but they SHOULD be... :)

Wet weather testing
 

BRP open test day. Rained early in the day so we got everything good and soaked, tried different tires, defroster, wipers, abs and whatnot. Gradually dried out all day and was finally dry when we left around 1pm. Went from tippy toeing around short shifting, looking offline for grip to hammering through the esses in 5th at about 110mph in the last session.

We were playing around with a big rear spoiler config matched with different tires trying to get a read on what combos would be best for what conditions. Since weather and track were changing all day, we were chasing pressure all day. So every time Sonny or I rolled out of the pits its was an easy lap to get a feel for the changes before going for it. A few laps to stabilize lap times and generate some driver feedback then back in to try the next combo. It's actually more tiring than just staying out the whole time. For the big test days I like to bring another team driver to switch off with. Easier to stay fresh and sharp that way. Otherwise, 6 hours in the seat in one stint with a constantly broken rhythm of frequent pit stops melts your brain.

Based purely on analytic research, I believe this to be the most optimum configuration. The later gaskets appear to starve the front of the head for upwards-flowing coolant, which is a good compromise given the front-mounted thermostat, however I believe the most optimal cooling system configuration to be precisely what Emilio has implemented- the nearly-model gasket combined with a rear-thermostat reroute.

My god, that torque curve look DELICIOUS! What a great advantage to be able to avoid shifting so often. Fewer gear changes = less wear and tear AND less chance for over rev/missed shift/etc. You've done this right!

BTW, nice hand work there, brother! Nice to see you drive through the moments where the car gets very unsettled but then comes back to you...

Linkie to dyno plot?

I think since Dean is on the team, he gets access to privileged info.

Won't be posted as far as I'm aware.

I'm pretty sure Dean hasn't seen it (neither have I!) but its very apparent from the video Emilio posted.

Nick's right - I was just commenting on what I was seeing in the video - the strong acceleration out of corners where Emilio is not downshifting where you might expect him to.

Is that the 1" wilwood brake master in the first post? Which booster are you using with it?

I'm trying to decide between the NA or thin/msm NB booster. I give up trying to modulate the brakes with the fat NB booster and the v8r brake kit.

NB1 base model manual booster. Our brakes are a bunch smaller than your but the modulation is fantastic, effort just a little less than stock. Dumb luck in my case. I figured I'd start somewhere and just keep trying boosters until I got the pedal I wanted. Stock boost from that tub was perfect.

I have driven an NA6 with the full V8R kit and it was overboosted. Too little effort and not much feedback. Apparently, booster choice is critical.

Im trying to figure out sizes so I can just ditch the booster. How about a full V8R kit with no booster? what caliper piston sizes do they run?

Bob

Goodwin front, Wilwood front, V8R rear 1.38" piston 120-6806 caliper
V8R front 1.75" piston 120-6816 caliper

Then they run 1.38 4 piston in the rear with 1.75" 4 piston in the front?

Seems like you wouldnt need a booster at all?

It's like double the clamping force for the same pedal effort.

Bob