oldManTan

i know the SC has a few different stock spoilers. just wondering what are the downforce figures on all of them? i'm guessing the 97+ has a little more downforce since it's actually a wing and not a very flat spoiler. or i maybe wrong. also open to discussion are other wings or spoilers that people have used on their SCs. get like a fitment/info/archive thread of spoilers and wings going. or maybe point me in the right direction towards a thread like this if it exists and bring that back.

oldManTan

absolutely no one? nothing at all lol?

eknine9

iTrader: (8)

They're most likely all negligible and if they aren't run through the trunk an bolted to the frame all of that downforce will mainly go into flexing the trunk than into pushing the suspension into the ground. Unless you plan on serious bodywork I wouldn't count on a spoiler producing much usable downforce.

I mean maybe... MAYBE... if it was attached to some particulary strong body panel and near the corner of it so it wouldn't bend and then that body panel was connected to the frame somewhere efficiently to apply that downforce to the wheels those numbers would be worthy, but I wouldn't count on any performance changes from a spoiler to our cars.

KahnBB6

iTrader: (5)

I'm not sure the OEM spoilers did more than change the styling of the SC/Soarer although they undoubtedly changed the Cd number. The SC/Soarer had two different spoilers: one flat one prior to 1997 and the slightly raised one in 97-2000 cars. I have also seen a slightly taller one which *looks* like it might have been optional on JDM Soarers (probably 2.5GT models) or it could have been an aftermarket part. It is very, very similar looking to the 97-2000 OEM spoiler only it is raised more.

The big OEM wing on the MKIV Supra actually did generate some mild downforce at higher speeds at the expense of raising the drag coefficient. I'm not so sure Toyota was going for the same thing when they made the optional SC/Soarer spoilers.

Though it doesn't cover our vehicles the video below is very informative as to how one measures these things.

RedMansSC3

iTrader: (3)

Very interesting video. Good share man.

oldManTan

interesting video indeed, but i was in class early in the morning and fell asleep watching it lol. gonna relisten to it now while i do some work. i think mounting a wing on the corners of the trunk where it meets the quarter panels would be a stiff enough spot dont you think? it's pretty thick sheet metal there. i'm just looking for way to make the car slightly more stable at higher speeds. going about 80 and you wiggle the wheel and the car wiggles a little longer. i have coilovers on the stiffest setting so my suspension is ok. maybe a rear diffuser would help slightly with the fins on the bottom. what about the roof fins that evos have?

KahnBB6

iTrader: (5)

Roof fins found on Evolutions, some STI's and I think (could be wrong) some BMW M3's and Benz Black Series cars are meant to cut the air stream and redistribute the airflow before a downforce area can be reached. I'm out of my league in my understanding of fins though.

I have no wing on my car and have a set of 600fr/325rr coil overs with a TT rear sway bar, an LSD and 255 width tires. Alignmnent is a modified "Lance" spec. I don't have any extra rear wiggle at 80mph-90mph. There was before I sorted out my bushings and alignment though.

Going with an aftermarket aluminum wing is quite extreme and I'd highly suggest checking your rear differential bushings (aftermarket is all that is available), steering rack bushings (aftermarket Daizen) and rear end links and lower control arms first before going that far.

There has to be some more data on the 97-00 wing or that other JDM wing.

oldManTan

yea i need to check my bushings and end links. i already have poly diff bushings and i'm pretty sure my front LCAs are from a supra with poly bushings. got the car like that. but the rear i'm not sure about. spring will be a busy time for me.

1997Soarer

iTrader: (1)

Not sure how true this is, but I read years ago that the 97 spoiler just decreases drag, about .01. 1997+ aero needs the spoiler to keep drag at the famous 0.31 figure the 92-96 with rear lip spoiler was famous for. The 97+ bumpers actually increase frontal area and trap air exiting under the vehicle. The side skirts are more looks than anything. My car came with one, and due to the shape it channels air behind the car. It has a flat shape on top but it's thinner at the front than at the rear. So its more of a wedge than anything.

Your 'wiggling' at 80 sounds a lot like the issue I was having with some middle tier tires I had when I had all factory suspension besides coils. I switched to Yokohama SDrives and the 80 shimmy went away. I still had soft feedback though... However, everything went away when I swapped out to Ikeya formula control arms. I also switched to SuperNow tie rods with daizen rack bushings. Steering is precise now, like the car is smaller/lighter and slight input causes the car to change lanes at highway speeds. I'm certain thats the feel you're looking for.

I agree with Kahn; you're gonna want to look at your rear suspension. Look at the rear uppers, rear lowers, the subframe, and swaybar. Also take a look at your front uppers and your tierods / rack.

You mentioned that your coils are set to stiff. Well, how stiff is stiff? I run 18k 12k. This makes it very stiff at low speeds but suits me very well at high speeds.

For the record, I went wingless for a month. Well, ok, I bought a carbon trunk lol. I noticed an increase in mpgs, (car looked cool too, like a giant torpedo lol) but the car would get unstable above 100. Due to the weight reduction I had done on the car, I was experiencing a too stiff rear setup, causing it to hop sideways on high speed turns on 294. I put the wing on after that.

oldManTan

i have DZ102 tires which i know aren't great, but they're pretty good i think, they're a really soft compound so maybe that's why, the max PSI on them is like 52 i think so the sidewall is pretty soft, i keep it at like 44 usually. i should probably replace my subframe bushings in the back to either aluminum or poly, the car has a new rear subframe though, that was replaced before i got the car so i need to check what bushings were installed with it.

all the tie rods and stuff will be changed down the line since they're not cheap so for now i guess i gotta deal with it and upgrade the smaller things that i can. bushings is the first step that's for sure.

Biddles

iTrader: (2)

I believe I saw it in a 1997 SC brochure that the new spoiler increases down force and improves handling. How much of course is up for debate, but it's cool that they said it anyway.