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Old 07-25-2016, 12:42 PM   #601
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Says the hundreds of kits sold and exactly zero issues reported Across this country, Canada, Europe, etc.... plenty of places with a lot more rainfall than where we are.

There are a couple spots in the engine bay you actually wouldn't want a vent directly over during a storm, so naturally we avoided those areas, and the template we provide means nobody will accidentally put the vents in the wrong place. We get the question about water probably once per week from someone who is guessing that is is an issue (as you are). We have a perfect record of it not being an issue for anybody.
I keep getting beer in in my engine bay, can you warranty?
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Old 07-25-2016, 12:47 PM   #602
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I bought this, but it doesn't fit.
NA Miata Aluminum Aero Undertray

Did a better job with DIY.
I have that now, fits but just. It does nothing for the sides of the radiator though.
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Old 07-25-2016, 12:50 PM   #603
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What part doesn't fit? Intercooler pipes?
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Old 07-25-2016, 12:58 PM   #604
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For me it rests right up against the bottom of the intercooler. Small spacers had to be used to attach it to the front air dam.

Driver side, leading edge needed to be trimmed for piping (through fender) . Passenger side, same thing plus a slot for the pipe to pass back into the engine bay to throttle.

If this where plumbed conventionally, then another hole would be needed for the driver side. Over the top plumbed intercoolers will need no modification to the tray.



Cliffnotes:

Anything you need to do to a factory tray, you will do to this one, but it's not floppy and hole saws work well.
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Old 07-25-2016, 01:12 PM   #605
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Re downflow/crossflow

Probably the same reason most intercoolers are crossflow and not downflow like early FM. All packaging constraints being equal, crossflow on the wider dimension of a rectangular shaped heat exchanger would allow more time for the fluid to exchange heat for a given volumetric flow. It may also allow. for some configurations, a multi-pass operation like the trackspeed setup. If radiators where square, I'd imagine design would be trivial between the two.
Bingo. Longer tubes = more efficient. Triple pass is also slightly more efficient because forcing the water through only 1/3 of the radiator increases the velocity of the water through the tubes, which improves heat transfer between the radiator and the coolant. This is why all high-end hot-rod radiators are both crossflow and triple-pass.
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Old 07-25-2016, 02:09 PM   #606
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Bingo. Longer tubes = more efficient. Triple pass is also slightly more efficient because forcing the water through only 1/3 of the radiator increases the velocity of the water through the tubes, which improves heat transfer between the radiator and the coolant. This is why all high-end hot-rod radiators are both crossflow and triple-pass.
This is really what I was grappling with. The fact of the matter is that longer tubes are not more efficient per se. As the coolant cools more, the delta T reduces and less heat transfer happens. So, that, by-itself, wasn't making sense to me.

The velocity thing makes perfect sense though -- and even single-pass cross-flow in a Miata configuration will have more velocity for a given flow rate than down-flow.

It also seems like you can improve the heat exchanger frontal area vs. tank frontal area ratio with crossflow?
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Old 07-25-2016, 02:11 PM   #607
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Originally Posted by ThePass View Post
Says the hundreds of kits sold and exactly zero issues reported Across this country, Canada, Europe, etc.... plenty of places with a lot more rainfall than where we are.

There are a couple spots in the engine bay you actually wouldn't want a vent directly over during a storm, so naturally we avoided those areas, and the template we provide means nobody will accidentally put the vents in the wrong place. We get the question about water probably once per week from someone who is guessing that is is an issue (as you are). We have a perfect record of it not being an issue for anybody.
Only issue I've ever seen was water leakage into the power steering reservoir. I suspect the person had a degraded O-ring. Apparently, they didn't report the issue . . . .
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Old 07-25-2016, 02:30 PM   #608
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This is really what I was grappling with. The fact of the matter is that longer tubes are not more efficient per se. As the coolant cools more, the delta T reduces and less heat transfer happens. So, that, by-itself, wasn't making sense to me.

The velocity thing makes perfect sense though -- and even single-pass cross-flow in a Miata configuration will have more velocity for a given flow rate than down-flow.

It also seems like you can improve the heat exchanger frontal area vs. tank frontal area ratio with crossflow?
Yup. The single largest factor in cooling efficiency, besides surface area is velocity of both air and coolant, assuming pressure remains constant. The I/C that TSE is using is a low tube count unit with I/O at opposite ends. The I/C that JR is using on their Rotrex kit, likewise is a long, low tube count unit with I/O at opiosite ends. Our crossflow is just a few percent more frontal surface area than the downflow.
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Old 07-25-2016, 04:19 PM   #609
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Quote:
Originally Posted by ThePass View Post
Says the hundreds of kits sold and exactly zero issues reported Across this country, Canada, Europe, etc.... plenty of places with a lot more rainfall than where we are.

There are a couple spots in the engine bay you actually wouldn't want a vent directly over during a storm, so naturally we avoided those areas, and the template we provide means nobody will accidentally put the vents in the wrong place. We get the question about water probably once per week from someone who is guessing that is is an issue (as you are). We have a perfect record of it not being an issue for anybody.
While I trust your info, I don't trust the populous to report issues. I park the car outside, at 8200 feet where it can hail literally any day out of the year, and snow every month except august.

I'm not putting hood vents (if i even need them, we will see) without a car cover. (which i need to get anyways lol)

Plus, I am a little girl. I'm all emotional. I feel better about it.
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Old 07-25-2016, 04:35 PM   #610
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Are you sure you don't have other issues, head gasket, pressure leak? Mine cycles between 205 and 195 (fan settings) even in hot weather. With just a single stock fan.
I hope not. Like i said, it only seems to happen when traveling at a high rate of speed. I've got a couple ideas i'm going to try, first being wiring the fans in parallel.
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Old 07-25-2016, 04:37 PM   #611
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Theoretically fans will just impede air. At high speeds its all about forcing air in with ducting, and letting it out of the engine bay somehow. Fans would actually be a restriction.
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Old 07-25-2016, 04:37 PM   #612
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Originally Posted by psyber_0ptix View Post
I have that now, fits but just. It does nothing for the sides of the radiator though.
I bought one for my NA and NB. The one for the NA fit so poorly, i ended up hacking it up and only using pieces of it to DIY. So i guess i got some use out of it.
It fit so bad i didn't even try to install it on the NB, which made me kinda sad. I may sell if someone wants it.
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Old 07-25-2016, 05:01 PM   #613
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I hope not. Like i said, it only seems to happen when traveling at a high rate of speed. I've got a couple ideas i'm going to try, first being wiring the fans in parallel.
Do you have AC in your car?

--Ian
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Old 07-25-2016, 05:11 PM   #614
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Do you have AC in your car?

--Ian
Yes sir.
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Old 07-25-2016, 05:13 PM   #615
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When was the last time you burped your coolant and how did you do it?
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Old 07-25-2016, 05:18 PM   #616
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When was the last time you burped your coolant and how did you do it?
Last time i lifted the front and started it until warmup, let it cool and repeated a few times was almost 2 years ago now when i installed the reroute.
But i have been checking it periodically throughout the season.
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Old 07-25-2016, 07:40 PM   #617
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Originally Posted by sixshooter View Post
My WRX vents are placed so water falls between engine and radiator. I don't want water in my spark plug holes and the location is good for pressure differential.

I'm using a crossflow triple pass stock-car racing radiator because I wanted to try it. I'm happy with it but it is all custom.
I was wondering about this as I drove by a WRX today. After reading a post earlier in this thread saying how as air rushed outwards with the singular vents, it prevented water from going into the bay once at speed. Looking at the WRX, using the vent as an air intake rather than exhaust I thought that lots of water would enter at speed. I knew Subaru would come up with a clever way around it.

Now I wonder how the Evo 8/9 deals with it, as the vent is more just a flat opening right over the turbo.
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Old 07-25-2016, 08:59 PM   #618
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I was wondering about this as I drove by a WRX today. After reading a post earlier in this thread saying how as air rushed outwards with the singular vents, it prevented water from going into the bay once at speed. Looking at the WRX, using the vent as an air intake rather than exhaust I thought that lots of water would enter at speed. I knew Subaru would come up with a clever way around it.
I'm not using the WRX hood inlet. I'm using the 2014 WRX front bumper side air outlets. I have since removed the little screens in the openings. They clip in.
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Old 07-25-2016, 11:50 PM   #619
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+1 copied sixshooters method with using front bumper side outlets. Works well enough, though have never done an hpde since installed
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Old 07-26-2016, 03:44 PM   #620
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Only issue I've ever seen was water leakage into the power steering reservoir. I suspect the person had a degraded O-ring. Apparently, they didn't report the issue . . . .
I didn't officially report the issue, but I did post about it in some thread about the louvers on here!

I replaced the o-ring and it helped a little, but didn't fully solve the issue. The small amount of water just makes the fluid look a bit milky. I'm sure over the years it would cause corrosion in the system, but I will yank the system out before then.
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