09-07-2022, 02:09 PM | #771 |
Senior Member
Join Date: Jul 2016
Drives: Subaru BRZ
Location: Atlanta, GA
Posts: 838
Thanks: 868
Thanked 562 Times in 337 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
|
Going with the Tomei baffle.
|
09-07-2022, 06:36 PM | #772 | |
Senior Member
Join Date: May 2019
Drives: 2022 GR86
Location: Between Sonoma and Laguna Seca
Posts: 1,707
Thanks: 2,129
Thanked 1,297 Times in 718 Posts
Mentioned: 30 Post(s)
Tagged: 1 Thread(s)
|
Quote:
As some people don't have time to click every link in this 50+ page thread, but those photos are very important to understand what's going on, I'll take the liberty to re-post them here:
__________________
Follow the build thread for my GR86!
|
|
09-07-2022, 07:28 PM | #773 | |
Senior Member
Join Date: May 2011
Drives: '23 BRZ
Location: Providence, RI
Posts: 4,584
Thanks: 1,377
Thanked 3,891 Times in 2,032 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
|
Quote:
I would say that while the upper screen portion may only be ~15% of the screened area, it is by far the most important 15%! The fluid can easily pass through the open areas on the screen as it's traveling perpendicular to it. On the sides, the flow is roughly trying to flow more parallel with the fluid flow. It's going to present much more of a blockage, and in addition will locally force the flow more perpendicular to the direction it needs to be going in. Something of a WAG but I'd say blocking off the top portion of the screen only and leaving the sides open could represent something like a 50% blockage... Might be OK for piddling around at low rpm but I would *not* want my car to be taken above 5k rpm with any frequency with that kind of blockage. Last edited by ZDan; 09-08-2022 at 08:10 AM. |
|
09-07-2022, 07:29 PM | #774 | |
Senior Member
Join Date: Jul 2014
Drives: 2020 Hakone
Location: London, Ont
Posts: 69,845
Thanks: 61,656
Thanked 108,283 Times in 46,456 Posts
Mentioned: 2495 Post(s)
Tagged: 50 Thread(s)
|
Quote:
It does support the theory that there is more than just the plugged pickup at work though.
__________________
Racecar spelled backwards is Racecar, because Racecar.
|
|
09-07-2022, 07:40 PM | #775 | |
Senior Member
Join Date: May 2019
Drives: 2022 GR86
Location: Between Sonoma and Laguna Seca
Posts: 1,707
Thanks: 2,129
Thanked 1,297 Times in 718 Posts
Mentioned: 30 Post(s)
Tagged: 1 Thread(s)
|
Quote:
My most conservative eyeball estimate is that each of the larger sides has 3x the surface area of the top; and the smaller sides are at least as large as the top. That gives the top at most 1/9 of the total surface area (~11%), and more like <10%.
__________________
Follow the build thread for my GR86!
|
|
The Following User Says Thank You to timurrrr For This Useful Post: | AndyRC (09-09-2022) |
09-07-2022, 07:43 PM | #776 | |
Senior Member
Join Date: May 2011
Drives: '23 BRZ
Location: Providence, RI
Posts: 4,584
Thanks: 1,377
Thanked 3,891 Times in 2,032 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
|
Quote:
I certainly wouldn't look at blockage of that area and conclude that it's no big deal... |
|
09-07-2022, 08:23 PM | #777 |
Senior Member
Join Date: May 2011
Drives: '23 BRZ
Location: Providence, RI
Posts: 4,584
Thanks: 1,377
Thanked 3,891 Times in 2,032 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
|
Also, even though the outer tube bulges out a bit, if the central area is blocked, the flow around the sides is going to have to make a hard turn to fill in behind the blockage, creating opposing vortices that will further act to reduce flow. Probably not as bad as trying to run fluid the "wrong" way through a Tesla valve but kinda in that direction...
Last edited by ZDan; 09-07-2022 at 09:00 PM. |
The Following 3 Users Say Thank You to ZDan For This Useful Post: |
09-07-2022, 09:00 PM | #778 |
Senior Member
Join Date: Jul 2014
Drives: 2020 Hakone
Location: London, Ont
Posts: 69,845
Thanks: 61,656
Thanked 108,283 Times in 46,456 Posts
Mentioned: 2495 Post(s)
Tagged: 50 Thread(s)
|
Damn we were writing at the same time!
__________________
Racecar spelled backwards is Racecar, because Racecar.
|
09-08-2022, 09:42 AM | #779 | |
Senior Member
Join Date: May 2011
Drives: '23 BRZ
Location: Providence, RI
Posts: 4,584
Thanks: 1,377
Thanked 3,891 Times in 2,032 Posts
Mentioned: 85 Post(s)
Tagged: 0 Thread(s)
|
Quote:
Also consider the cross-section of the tube where the top of the screened box is, and the area of the top of the screen relative to *that* cross-sectional area and not relative to the total screen area. And *also* consider that with all screens clear the flow velocity in the *middle* of that area (i.e. the horizontal upper screen area) is greater vs the perimeter. Blocking out the upper horizontal screen (middle of that area) is gonna be very bad for total flow rate... |
|
09-08-2022, 10:13 AM | #780 | |
Senior Member
Join Date: Jul 2014
Drives: 2020 Hakone
Location: London, Ont
Posts: 69,845
Thanks: 61,656
Thanked 108,283 Times in 46,456 Posts
Mentioned: 2495 Post(s)
Tagged: 50 Thread(s)
|
Quote:
Cramming a square filter into an oval tube that tapers in immediately after the box ends isn't giving a pile of clear flow around those sides either.
__________________
Racecar spelled backwards is Racecar, because Racecar.
|
|
The Following User Says Thank You to Tcoat For This Useful Post: | AndyRC (09-09-2022) |
09-08-2022, 10:19 AM | #781 | |
Senior Member
Join Date: May 2021
Drives: GR86
Location: Kansas
Posts: 323
Thanks: 168
Thanked 249 Times in 139 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Quote:
Foreign objects in a fluid flow will get caught in a screen at the point of higher flow first, because there is more/stronger flow in those locations. If a piece of RTV got sucked onto the side before the end was completely blocked the flow through the open part of the end would pull that RTV along until it filled that gap. It's a fairly simple way to test where your flow is strongest. |
|
The Following 4 Users Say Thank You to Spektyr For This Useful Post: |
09-12-2022, 01:34 PM | #782 |
Senior Member
Join Date: Oct 2013
Drives: '22 BRZ
Location: PA
Posts: 1,833
Thanks: 2,298
Thanked 1,472 Times in 767 Posts
Mentioned: 24 Post(s)
Tagged: 2 Thread(s)
|
I'm glad Dan was able to succinctly explain what I've been trying to explain to the morons on facebook that are always like "omg that's so little blockage" because they don't understand fluid dynamics in the least.
__________________
|
The Following 3 Users Say Thank You to DocWalt For This Useful Post: |
09-20-2022, 10:10 AM | #783 |
The guy w/o an FRS or BRZ
Join Date: Sep 2019
Drives: '23 GR86 Premium 6MT Halo White
Location: Planet Erf
Posts: 446
Thanks: 276
Thanked 399 Times in 215 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Noob questions: I see the diameter of the pickup tube. How much oil is being sucked up at once? Is it a slow suction or fast? (not sure how to quantify this, maybe in cups per second or quarts per minute?)
If RTV is to be sucked up in there, is it instant? (slower/weaker flow, happens over time; faster/stronger flow, happens "instantly" or much quicker) Could the tube be under-sized? (I know, regardless of size, a blockage leads to starvation) |
09-20-2022, 10:20 AM | #784 | |
Senior Member
Join Date: May 2021
Drives: GR86
Location: Kansas
Posts: 323
Thanks: 168
Thanked 249 Times in 139 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Quote:
As your pickup tube diameter increases beyond the size of the oil pump inlet you're going to see less flow around the outside because the pump cannot lift the entire volume of oil in the tube uniformly. The height of the column of oil is set, so the wider you make the pickup the heavier that much oil becomes and the pump has only so much lifting power. The result will be a column of oil within the total volume that actually moves upward, concentrating any particulates or chunks suspended in the oil to that part of the screen. As the center of the screen gets blocked, the column will "hunt" around for an unblocked path, kind of like a tornado looking for a trailer park. Again, I'm not certain, but my guess would be that the smoothest, most efficient (laminar) flow would be achieved when the tip of the pickup tube is at or very close to the same surface area as the inlet of the oil pump, so I doubt that it's undersized. |
|
The Following User Says Thank You to Spektyr For This Useful Post: | DocWalt (09-20-2022) |
|
|
Tags |
oh no not again |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
New stock GR86 '22 Dyno Runs: Twins packing more power than advertised!! | steel86gt | GR86 General Topics (2nd Gen 2022+ Toyota 86) | 14 | 03-09-2022 01:15 AM |
Driver's side window seal/door seal | KAB-FRS | Issues | Warranty | Recalls / TSB | 255 | 01-01-2021 06:09 PM |
Is my engine blown? | dallenj | Engine, Exhaust, Transmission | 39 | 01-30-2017 04:18 PM |
Blown engine due to 0W-20? | Benschneider06 | Engine, Exhaust, Transmission | 45 | 07-23-2015 02:33 AM |
Subaru BRZ complete engine gasket & seal kit 2.0L | JPxM0Dz | Engine, Exhaust, Transmission | 0 | 12-18-2012 11:11 AM |