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TRS · 11-12-2022, 05:52 AM

Hello all,

actually this post is more a question. But I didnt know where Else to put it since, surprisingly, there is no section for functional aero mods in the forum. (Or Im just too dump to find it)

So first things first, here is a pic of my self developed rear diffuser:

Now my question: Im considering to aim for the 200mph mark. Is somebody arround here expierienced with high speed behaviour of the 86 chassis in matters of aero?

To be very clear right away, I do NOT talk about giant Front splitters for timeattack racers. The car is and shall be street legal (in Germany if you know what I mean...). Im currently investigating my options to reduce overall drag while improving or at least keeping downforce (or better said lift) conditions of the car. In order to maybe giving kind of a frame, the inspiration/attitude of this build is the YellowBird Porsche. (What does not mean that I would actually compare my build with this masterpiece of automtive engineering)

Currently Im topping at round about 185-188mph, depending on conditions. The car feels still stable at those speeds and already accepted a little jump at arround 180mph without getting nervous. I had oversean a bump in the road what caused short lose of ground contact.

My current aeromods are minor. I have a guided radiator airflow by a radiator scoop & ducting, a vented hood (equal seibon TS Style), a bottom line kit equal to HT Autos (which was more intended for optical appearance, but the front lip actually makes a mesureable difference in top speed) and my rear diffuser. The car is slightly lowered on B16 coilovers, front Ride height about 3" and round about a 1" rake. Rims are currently way to wide and sticking out the fenders, what is one of the first things I will adress for drag reduction.

My planned further steps:
-changing 9.5" to 9" wheels with a Offset to ensure they are not sticking out the front silhoutte
-full flat underbody with a small exemption near the differential since I otherwise have no options to route a big enough exhaust pipe
-increasing power from currently 450 to ~520 flywheel hp
-custom setup Öhlins coilovers with spring rates and valving to match my exact wheel loads and as well some more freedom for Ride height adjustment without blocking out the dampers (Im expecting some gains concerning drag with slightly lower ride height, Im aiming for about 2" Front)

So If theres anybody out there having expierience with modifications of the 86 chassis for this kind of aero I would appriciate any contact to exchange some thoughts and knowledge.

PS: Mods, If theres any better section for this Post, please move...

Thanks in advance!

11-12-2022, 05:52 AM	#1454
TRS Senior Member Join Date: Nov 2019 Drives: 2013' Toyota 86 (EU spec) Location: Germany Posts: 160 Thanks: 32 Thanked 139 Times in 56 Posts Mentioned: 4 Post(s) Tagged: 1 Thread(s)	Hello all, actually this post is more a question. But I didnt know where Else to put it since, surprisingly, there is no section for functional aero mods in the forum. (Or Im just too dump to find it) So first things first, here is a pic of my self developed rear diffuser: Now my question: Im considering to aim for the 200mph mark. Is somebody arround here expierienced with high speed behaviour of the 86 chassis in matters of aero? To be very clear right away, I do NOT talk about giant Front splitters for timeattack racers. The car is and shall be street legal (in Germany if you know what I mean...). Im currently investigating my options to reduce overall drag while improving or at least keeping downforce (or better said lift) conditions of the car. In order to maybe giving kind of a frame, the inspiration/attitude of this build is the YellowBird Porsche. (What does not mean that I would actually compare my build with this masterpiece of automtive engineering) Currently Im topping at round about 185-188mph, depending on conditions. The car feels still stable at those speeds and already accepted a little jump at arround 180mph without getting nervous. I had oversean a bump in the road what caused short lose of ground contact. My current aeromods are minor. I have a guided radiator airflow by a radiator scoop & ducting, a vented hood (equal seibon TS Style), a bottom line kit equal to HT Autos (which was more intended for optical appearance, but the front lip actually makes a mesureable difference in top speed) and my rear diffuser. The car is slightly lowered on B16 coilovers, front Ride height about 3" and round about a 1" rake. Rims are currently way to wide and sticking out the fenders, what is one of the first things I will adress for drag reduction. My planned further steps: -changing 9.5" to 9" wheels with a Offset to ensure they are not sticking out the front silhoutte -full flat underbody with a small exemption near the differential since I otherwise have no options to route a big enough exhaust pipe -increasing power from currently 450 to ~520 flywheel hp -custom setup Öhlins coilovers with spring rates and valving to match my exact wheel loads and as well some more freedom for Ride height adjustment without blocking out the dampers (Im expecting some gains concerning drag with slightly lower ride height, Im aiming for about 2" Front) So If theres anybody out there having expierience with modifications of the 86 chassis for this kind of aero I would appriciate any contact to exchange some thoughts and knowledge. PS: Mods, If theres any better section for this Post, please move... Thanks in advance! __________________ Follow me on YouTube Last edited by TRS; 11-12-2022 at 06:03 AM.