Page 5 of 5

Re: st 205 water to air intercooler MOD,St215

PostPosted: Thu May 04, 2017 4:26 pm
by soarer.jzz30
Yes, that's what you're worried about isn't it.
That harsh angle that's hard to get around. The only difference between ours is on the far side his has less angle right before the throttle body. If i cut that flat panel of mine and peeled it up, then resealed it to have less angle than would you agree the issue is resolved.

Sent from my SM-G935P using Tapatalk

Re: st 205 water to air intercooler MOD,St215

PostPosted: Thu May 04, 2017 4:29 pm
by soarer.jzz30
Also, one quick note, the St215 Ata top mount isn't designed like jdm's. It has a slight angle on the left and thats it. It doesn't wrap all the way to the one side.
Not that that means anything as I have no data of efficiency and no comparisons.

Sent from my SM-G935P using Tapatalk

Re: st 205 water to air intercooler MOD,St215

PostPosted: Thu May 04, 2017 5:50 pm
by Redrkt01
Ok, so I'm not at all concerned with turns whether the turn is harsh or not. A discussion about turns, angles, et cetera is basically a discussion about CFM. That's not my point. My point, whether it can be measured or not, is about heat transfer. This is true whether we're talking about a pressurized FI air charge or NA air. So pressure has nothing to do with it.

If, for some reason, we were to run an intercooler on a normally aspirated motor my point would still have merit. At normal atmospheric pressure we could take a charge of air and blow it through a square intercooler. Divide the square into right and left halves. Cut a hole at the top right and bottom right ends. This is your intercooler. Now imagine that it has no core, that it's just an empty box. As a stream of air moves from the bottom right inlet to the top right outlet the air that is on the left hand side of the box will move in an counterclockwise elliptical pattern separately from the inlet-to-outlet airstream. Very little of the air from the stream moving from inlet to outlet gets mixed with air on the left side. And very little of the air moving in the ellipse bleeds into the straight line stream. You can actually see it in action when you're driving on the interstate and someone has a bunch of styrofoam cups and paper trash blowing in a circular ball behind the cab of a pickup truck. As long as the truck stays the same speed the trash has very little opportunity to make it into the slipstream going over the cab roof and over the top of the bed.

The same thing is happening in the intercooler in your setup. Except instead of it being an empty box your intercooler has a core. All that really does is prevent elliptical airflow. The passenger side of the intercooler isn't receiving a lot of fresh(new,hot) air to cool and that air is just kind of hanging out and bouncing around. So my point is that the way you've directed the air through the intercooler fails to make full use of the core to lower temps as much as possible. And again, it doesn't matter if it is turbocharged air or not. Fluid dynamic principles (aerodynamics) do not change based on if the fluid is pressurized or not. You can remember that fact when thinking about this in the future by reminding yourself that liquid fluids such as water cannot be compressed. Water would move through the intercooler the same way air does.

In my first post to you I said that your reasoning that pressurized air will flow through the core the same no matter where the outlet is located is incorrect. I said that based on your comment saying "I assume if it's pressurized air, that it will expand to every part of the system and therefore probably not affect performance much." I'm just saying that's not how fluid dynamics work. I don't think you have an issue, per se. But I do think that if we swapped out your 205 IC for JDMSD1's you'd have lower temps. And I say that having no idea what your temps are. It's all just something to consider for next time. Either way, great job taking the initiative to get a W2A system on the 215. Both of you are inspiring me to get off my ass and do something with the spare 215 motor I have sitting in the garage.

Re: st 205 water to air intercooler MOD,St215

PostPosted: Thu May 04, 2017 6:13 pm
by soarer.jzz30
So, with this in mind, considering most large fmic have essentially the same left to right (if you turn the wta sideways) so by the same merit it would be better to just run a smaller intercooler because the air never "passes" through it?
Not being condensending I just want your thoughts

Meaning hot spots in any intercooler where there is a great offset.

I'd definitely like to rip into it again one day to make it more like his.
But at that point I'd probably just go fmic.


Sent from my SM-G935P using Tapatalk

Re: st 205 water to air intercooler MOD,St215

PostPosted: Thu May 04, 2017 6:48 pm
by Redrkt01
I've never ripped into a FMIC, but usually I see what I'll call "endcaps".....where the standard pipe diameter expands to the full height of the core over a distance of a few inches. That allows the air to sort of spread out before it moves across the core. In most FMICs we see out there I doubt the air has enough time to completely spread out from bottom to top. The more time (distance) air has to go from a standard pipe diameter to a widening funnel towards the core, the more efficient the core will be. Similarly, if the piping enters and exits the core from the middle (rather than the top or the bottom) I think that would be more efficient. But it all really depends on what's happening on the inside.

And yeah, if there are big offsets then you're gonna see hotspots. In any intercooler just as you said. Even JDMSD1 is going to have a couple hotter spots in a couple of corners. To be sure, bigger is usually better since you're gonna have more core to cool air. But depending on the design you could have a lot of unused sections of the intercooler. I'd bet that if you looked at certain configurations in infrared you'd see lots of hot spots. There would definitely be situations where a guy could've gotten away with buying a smaller intercooler because 45% of his core surface area isn't really being used. But it all depends on the situation and the construction. I'm not saying that it's always true, but your scenario where you could go smaller and get the same temps could certainly happen.

Re: st 205 water to air intercooler MOD,St215

PostPosted: Thu May 04, 2017 6:50 pm
by Redrkt01
.

Re: st 205 water to air intercooler MOD,St215

PostPosted: Thu May 04, 2017 6:54 pm
by soarer.jzz30
Well I hope the tumbling air means it won't build up too bad, seeing how the water flows over the whole thing, it should do it's job and at least neutralize some of that offset heat. I also think that since the most I plan to run this on is like 20-22, the Temps should be OK at least.
Anything higher I bet it would heat soak because it couldn't keep up with the flow

Sent from my SM-G935P using Tapatalk

Re: st 205 water to air intercooler MOD,St215

PostPosted: Sat May 06, 2017 4:03 pm
by JDMSD1
Redrkt got it right. Thanks man.

Nice quiet return system.no pop and whistle. I used a stock bov for a friend who wanted quiet.
I like the noise. I'm actually gonna have a muffler this time,lol

Re: st 205 water to air intercooler MOD,St215

PostPosted: Sat May 06, 2017 5:32 pm
by JDMSD1
I originally wanted to make this IC for my AW113SGTE,
Which I scrapped to build this ST185..
I need it for the dessert I live in,hope it's good to 21psi.
Had a custom (by me)front mount system on last celica,
My friend complained of "turbo lag",so I'm trying this out.