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Gotta say i've been super busy with work the last couple months and the winter weather has me focused on other projects aside from the lexus but I come back and see the level of quality and cool that you've been up too making that oil cooler duct. Seriously makes me feel the need to step up the quality in my build cause hot damn you've invested some time and thought into that creation alone. I applaud you dude!
Honestly it seems only the OG's chill on the forums any more, i usually check on my weekends casually but my build thread will be pretty quiet until warmer weather comes until i get a shop at least but that isn't any time soon.
Thanks a lot for the kind words!
Yeah, it's kind of weird on the forums nowadays lol I remember when the forums used to be REALLY active in the 2000's and early teen's. Now, everyone's on FB asking the same "what turbo should I get?" questions....ehhhh...The thing I worry about is losing content on the forums if not active enough.
Wow. This is my first time seeing your thread and I’m immensely impressed! This is the most 21st century build I’ve seen on these forums! Well done.
I think you should monetize your work (a little lol) — people like me would love high quality parts like the oil cooler ducts you’ve designed, but with no experience, two kids and a career, just don’t have the time to learn. But, I could buy a 3D printer and use your files! Might be worth it to make a few bucks back on your end and the community would benefit tremendously.
Now for my unsolicited and lay person advice (loll). I wonder if your high beam vents wouldn’t be best used as a source of low pressure, rather than a direct vent? In other words, if you ducted them behind the radiator, thus increasing the flow and decreasing the pressure behind said radiator, you would induce greater flow from the high pressure in front of the car? If not, then capping them may be best and ducting from the radiator to the hood vents, like this Supra:
My second hare brained idea is to use the center slit vent in the nose of the bumper as the inlet for your engine. It’s quite a large plenum in there and otherwise unused for most. If that area inside the nose were to be sealed up and you plumbed the turbo’s inlet to it, you could have a bountiful source of cool, fresh air to pull from. This would free up both of the lower inlets for your oil cooler(s) and keep the temps as low as possible. You may need/want to enlarge that nose opening, but I know the bumper is freshly painted so perhaps that’s a non-starter for you. I’d tend to believe though, that it could flow enough air as-is, especially if you could perhaps divert the driver’s side high beam vent into this “plenum” as well, though this may just introduce turbulence without much actual benefit.
I happen to find aerodynamics fascinating and I’ve thought to myself quite a bit how I would do it “one day”, so to see it coming to life here is really cool. I’ll check back with the build and wishing you luck!
Nick
EDIT: I missed your earlier post showing the ducting of the radiator to the hood, as I suggested. I’m surprised it’s not sufficient to pull that air more efficiently. Why do you suppose that is?
I really appreciate your kind words! I was surprised to see any responses to my mumbo jumbo lol I'm glad people find this stuff sorta interesting.
I hear you on the monetizing part, my wife and friends have been pushing me to get into the "youtube" stuff. I don't really like the exposure and I'm an undercover introvert lol I'm warming up to the idea though. As far as duct files and what not, I have no problem gifting these to hobbyists in the community possibly a different arrangement with people wanting to make profit off of it.
That Supra in the link is very cool. My radiator exit duct almost looks identical.
I think we have/had the same thought. My thought/idea about the high beam opening was to introduce high pressure, fresh air directly to the radiator (without having to go through the intercooler. It wasn't meant to be a vent. However, what ended up happening is air is fed from 2 opposing sources (the two high beam sides), virtually hitting a wall (radiator), then travelling sideways and swirling/circulating pretty violently. The front bumper opening makes matters even worse. I predicted some of this behavior but it was difficult to predict the severity. Adding vertical fences in that area would restore or mitigate most of that circulation.
That radiator/intercooler/ high beam area is definitely complex, flow-wise. I have the swirling/circulation problem in the upper portion between the high beam opening and radiator. Additionally, the air flowing back to avoid going through the radiator and flows above the hood instead. Then, air is swirling in the lower portion between the intercooler and radiator. Some of it is also avoiding going through the intercooler. Tricky area to optimize and definitely needs more work.
To answer the question about why it may not be pulling air more efficiently; It's all about pressures, or pressure differential to be more precise. If pressure at point A is higher than pressure at point B, then air will flow from A to B. The higher the difference in pressure, the faster the air will move. If pressure at point A is not that different from pressure at point B, it won't move, and it won't care how fancy the ducting is between A & B. In this case, I think pressure is dropping drastically across the intercooler, then drops some more across the radiator. In addition, the exit strakes are not sticking out enough to cause a low enough pressure at the exit. So, flow is probably not that great. I can't even imagine how much having a condenser will decrease performance even more (I took my condenser out).
By the way, I'm already planning to feed the turbo from the right fog light opening. Initially, I wanted to feed it from the HB opening instead. I may still go back and tap into the high beam/ radiator area and feed the turbo from there.
Appreciate your brainstorming I'm always brainstorming about this stuff, sometimes in my sleep haha
MadMax,
It seems that Nick has got some very interesting comments regarding your fantastic finds. Boy two great minds.
I have a question, you were showing the rear of the car and mentioned the "Horned Owl" effect. Could this be eliminated by using a rear window spoiler instead of the trunk spoiler ( or with both ). Just thoughts from an old fellow.
Bill
Hi Bill, always good to hear from ya.
The "horned owl" comment was more of me being silly than being an effect haha The rear view has what looked like the horns on a horned owl lol The "horns" are those strong vortices crawling on the A pillars and flow all the way to the rear. Yep, just me being silly lol
I don't think you can get rid of the "horns" or the A-pillar vortices. Additionally, I think that's the best form of A-pillar vortices (on the SC). That vortex is basically all the air hitting the windshield, causing a high pressure area, and trying to find a route around the car. Some go over the roof and some go around the A-pillar. The portion that goes around A-pillar can't turn fast enough and tumbles/swirls violently, forming the A-pillar vortex. Lexus did some work to optimize that vortex. This's why you don't hear buffeting when you open the windows. The angle of the A-pillar is a big factor. A lot of cars and SUV are notorious for the annoying/disturbing buffeting noise when you open some windows.
Sharp edges in the rear (or front) help to control and predict air flow. They force air to separate exactly at the edge, thus making it predictable. The same can't be said about rounded surfaces, especially in the rear, like on a naked trunk (without spoilers or flaps). Having rounded surfaces on the back of the car cause unpredictable or unsteady cyclic flow. This can/will cause drag and instability at high speeds.
We did a lot of work with a small air tunnel during engineering school that used an airfoil with various ports on it to read air pressure, speeds, etc. I love you work with the aero on this car and I'd love to have the time and resources one day to design and build some aero parts for myself. Keep up the awesome work - I'm loving it!
I really appreciate your kind words! I was surprised to see any responses to my mumbo jumbo lol I'm glad people find this stuff sorta interesting.
I hear you on the monetizing part, my wife and friends have been pushing me to get into the "youtube" stuff. I don't really like the exposure and I'm an undercover introvert lol I'm warming up to the idea though. As far as duct files and what not, I have no problem gifting these to hobbyists in the community possibly a different arrangement with people wanting to make profit off of it.
That Supra in the link is very cool. My radiator exit duct almost looks identical.
I think we have/had the same thought. My thought/idea about the high beam opening was to introduce high pressure, fresh air directly to the radiator (without having to go through the intercooler. It wasn't meant to be a vent. However, what ended up happening is air is fed from 2 opposing sources (the two high beam sides), virtually hitting a wall (radiator), then travelling sideways and swirling/circulating pretty violently. The front bumper opening makes matters even worse. I predicted some of this behavior but it was difficult to predict the severity. Adding vertical fences in that area would restore or mitigate most of that circulation.
That radiator/intercooler/ high beam area is definitely complex, flow-wise. I have the swirling/circulation problem in the upper portion between the high beam opening and radiator. Additionally, the air flowing back to avoid going through the radiator and flows above the hood instead. Then, air is swirling in the lower portion between the intercooler and radiator. Some of it is also avoiding going through the intercooler. Tricky area to optimize and definitely needs more work.
To answer the question about why it may not be pulling air more efficiently; It's all about pressures, or pressure differential to be more precise. If pressure at point A is higher than pressure at point B, then air will flow from A to B. The higher the difference in pressure, the faster the air will move. If pressure at point A is not that different from pressure at point B, it won't move, and it won't care how fancy the ducting is between A & B. In this case, I think pressure is dropping drastically across the intercooler, then drops some more across the radiator. In addition, the exit strakes are not sticking out enough to cause a low enough pressure at the exit. So, flow is probably not that great. I can't even imagine how much having a condenser will decrease performance even more (I took my condenser out).
By the way, I'm already planning to feed the turbo from the right fog light opening. Initially, I wanted to feed it from the HB opening instead. I may still go back and tap into the high beam/ radiator area and feed the turbo from there.
Appreciate your brainstorming I'm always brainstorming about this stuff, sometimes in my sleep haha
That’s interesting about the vertical fences. I hadn’t considered that you could fix all that turbulence with vertical fences. Pretty cool!
I had dreamt about building a car one day that would manage all the air that hits the nose of the car. Optimized cooling and some aerodynamic benefits, of course. For me, it’s more about just trying to always improve on the existing design. My car is and always will be strictly a road car. I’ll continue to follow your thread for more ideas and enhancements I can stea— uhh borrow lol
Will your oil cooler ducts work on a “stock” car? If so, I’d love to get that file. Would be for my own use, I don't even own a 3D printer yet but I’ve been thinking about getting one for just this kind of thing! Any advice along these lines would be much appreciated.
madmax,
Thank you for your most detailed message re my comments. I do understand your answers much better since you put it in information that I could understand.
Thanks again,
Bill
The "horned owl" comment was more of me being silly than being an effect haha The rear view has what looked like the horns on a horned owl lol The "horns" are those strong vortices crawling on the A pillars and flow all the way to the rear. Yep, just me being silly lol
I don't think you can get rid of the "horns" or the A-pillar vortices. Additionally, I think that's the best form of A-pillar vortices (on the SC). That vortex is basically all the air hitting the windshield, causing a high pressure area, and trying to find a route around the car. Some go over the roof and some go around the A-pillar. The portion that goes around A-pillar can't turn fast enough and tumbles/swirls violently, forming the A-pillar vortex. Lexus did some work to optimize that vortex. This's why you don't hear buffeting when you open the windows. The angle of the A-pillar is a big factor. A lot of cars and SUV are notorious for the annoying/disturbing buffeting noise when you open some windows.
Sharp edges in the rear (or front) help to control and predict air flow. They force air to separate exactly at the edge, thus making it predictable. The same can't be said about rounded surfaces, especially in the rear, like on a naked trunk (without spoilers or flaps). Having rounded surfaces on the back of the car cause unpredictable or unsteady cyclic flow. This can/will cause drag and instability at high speeds.
I hope that helps.
Two part question on this: what do you plan to do with the backend of the car? And, for those of us who are street focused, did you have any suggestions?
I’d be real curious to see what affect some of these duck bill spoilers have on this flow. Perhaps a factory spoiler is the best overall solution for street cars…?
We did a lot of work with a small air tunnel during engineering school that used an airfoil with various ports on it to read air pressure, speeds, etc. I love you work with the aero on this car and I'd love to have the time and resources one day to design and build some aero parts for myself. Keep up the awesome work - I'm loving it!
I'm getting some flashbacks, Rudy LOL I remember sitting in the control room watching our first project in the windtunnel. I think it was doing 120 mph or so. It suddenly started buffeting and just disappeared! We stopped the tunnel and reviewed the footage. It basically became a thousand pieces from the buffeting/flutter. My team of 6 spent the whole day walking through the tunnel sweeping and cleaning the floor.
I'm more than happy answering any questions you may have process wise, technicals...etc
As always, thank you for the encouragement
That’s interesting about the vertical fences. I hadn’t considered that you could fix all that turbulence with vertical fences. Pretty cool!
I had dreamt about building a car one day that would manage all the air that hits the nose of the car. Optimized cooling and some aerodynamic benefits, of course. For me, it’s more about just trying to always improve on the existing design. My car is and always will be strictly a road car. I’ll continue to follow your thread for more ideas and enhancements I can stea— uhh borrow lol
Will your oil cooler ducts work on a “stock” car? If so, I’d love to get that file. Would be for my own use, I don't even own a 3D printer yet but I’ve been thinking about getting one for just this kind of thing! Any advice along these lines would be much appreciated.
Nick
Yeah, based on my interpretation of the mechanism causing the swirling ahead of the rad, fences/strakes would counter that mechanism. The strakes would only improve/ encourage a normal/orthogonal flow through the radiator (perpendicular to the rad). I.e. no more swirling, at least a lot less of it. The majority of turbulence will still be there. However, it's at least heading in the right direction and not in circles lol
You're more than welcome to "borrow" lol my concepts. As long as you give me credit . I'll find that file and shoot it your way. It's important, though, to realize that most aero parts are not universally efficient or useful. Something that does good on my setup may not be beneficial on your setup. Some things can be beneficial across the board: Think fender liners, flat or smooth bottom, tire deflectors, trunk spoilers/flaps. Some of these items may even require optimization for each application. E.g. Tire deflectors.
The cooler duct may work ok on your car if you implement a couple of other things. Note the position of my oil cooler: it's directly ahead of the fender liner on a stock SC. This basically blocks any flow through the oil cooler. I don't have to worry about this because I don't have the OEM liner any more, and I plan on ducting the cooler exit as well. At a minimum, you would need to cut the liner section behind the cooler. Additionally, the area in front of the tire (behind the cooler) is a high pressure area due to all the air hitting the tire head-on. I'm planning on reworking the area ahead of the tire in order to lower the pressure behind the cooler. Without those 2 steps, flow won't be great through the cooler. FYI, tire deflectors are the easiest way to lower the pressure near the tires (see my early CFD posts that have tire deflectors in them). That's my take on interchangeability of aero parts.
Note the high pressure area ahead of the tires.
Regarding spoilers, I would stick to the OEM spoiler. I think there was another version that looked like a flap. Could have sworn it was on the SC400. I might be thinking of S13's.
This's the one I have
This's the one I was thinking of... Very classy in my opinion. However, its not OEM (VERTEX).
I think a flat bottom is a great solution, even for street cars. It doesn't have to be a one-piece floor. It can be multiple pieces. This really makes the car more efficient and stable.
madmax,
Thank you for your most detailed message re my comments. I do understand your answers much better since you put it in information that I could understand.
Thanks again,
Bill
I'm Baaack lol
2024 and 2025 have been HECTIC. Between work and family, there was almost no time to get any work done on the car- I turned the car on once in 2 years lol
HOWEVER, I'm back with a vengenace. A plan on multiple fronts is already in motion. First I decided to put the aero work on hold in favor of the mechanical stuff. "What mechanical stuff" you say.Well, for starters I decide that I want more than 5-600 WHP, 8-900 WHP is my new target. A lot of dominos are going to fall based on this decision. I will tackle them in parallel to be more efficient with my time.
First domino is my 13 YO fuel setup. Currently, I have a 10 gallon fuel cell mounted where the spare tire goes. which feeds a Bosch 044 pump pressurizing a 10AN into a Weldon FPR. The FPR then feeds the rail with dual 8an lines. Very simple setup. Pump gas only. I remember it approaching the limit on the dyno.
I'm ditching the fuel cell for safety reasons- going back to the stock tank. Stock tank has better capacity to support my long-wished fuel (E85). I'm also going to use dual Walbro 450's in-tank, feeding the same Weldon FPR. PTFE hoses will be used as well as other E85 supporting components.
These pumps look like they carry some punch...
Bulkhead connector to power the pumps
Bulkhead plumping to the pumps.
hmmmm I'm trying to figure out how to resize these photos....
Flex Fuel setup- I made a parallel line to the main feed line on the pessure side.
Man... this forum is becoming a ghost town lol is everyone on youtube now, Facebook?
I have noticed the traffic go down too but many of us are still very much here and active even if there is less discussion right now. If we're not actively posting about our SC's it doesn't mean we won't or don't still have them.
I haven't posted much about mine because there hasn't been a lot of progress lately that's very visually oriented. My car has been down for repairs for some time while I've had to focus most of my spare time on doing renovations to an old house mostly by myself.
I am just about to receive custom restored rear seats from an old school auto upholsterer in a couple of days and I've been collecting parts for a Haltech ECU conversion and have been working on some wiring repair, sunroof maintenance and will soon be doing a new sub-harness for extra sensors. I see others having posted some really cool updates to their SC's or Soarers over the last couple of months.
As for other community systems... personally I use youtube plenty for many interests but it's not anywhere close to being a replacement for this forum specific to our cars with our vast searchable wealth of information, pictures and discussions. I'm on Facebook (never use marketplace though) but again it's also not a replacement for this forum in my eyes. I'm on a couple of FB Soarer/SC groups and occasionally comment with info whenever helpful but since you can't search for anything there... you'll never find those posts again as a community resource the way you can with this forum and other car model forums.
I think a lot of the OG owners (including myself since I've been building Toyotas since the late 1990s) still love the feeling of permanence afforded by the forums.
Although I use social media for posting about my cars and projects, it's such a toxic and short lived place to post. No one has any attention span, and I feel almost like it's a throw away to post detailed posts there, whereas quick video links or 'look at me' stuff seems OK. For highly technical posts and build threads, the social media world has never been able to replicate old school internet forums, and I do really enjoy being able to follow projects from start to finish here.
@madmax98 your build is absolutely sick and I'm enjoying catching up on it! Best wishes for your progress in 2026 my friend.
possibly a different arrangement with people wanting to make profit off of it.
. I'll find that file and shoot it your way. It's important, though, to realize that most aero parts are not universally efficient or useful. Something that does good on my setup may not be beneficial on your setup. Some things can be beneficial across the board: Think fender liners, flat or smooth bottom, tire deflectors, trunk spoilers/flaps. Some of these items may even require optimization for each application. E.g. Tire deflectors.
