IW STi Forum banner

321 - 340 of 1193 Posts

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #323
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

So the ABS underbody panels I built for the "tunnel" area under the cabin of the car have warped pretty good... The "amplitude" of the waves is only about an inch or so, but I'm not satisfied and I think the "benefits" of the flat bottom are potentially not there as much now.

SO, I bought a 4'x8' sheet of 1/16" thick aluminum. I am in the process of cutting out the replacement panels. I had the sheet cut down to 2'x3' and 2'x2' sections to get them home and will weld some of them back together as needed. I will maintain the underbody in a couple large pieces just for ease of access to the bottom of the car. One giant sheet would be impossible to work with...

Heres the good news! Although I'm not finished yet, I am confident the aluminum panels are (while being more rigid and needing less support) will be lighter than the ABS panels! This is in part due to the extra hardware added to the ABS panels for rigidity.

I will take this opprotunity to add some stabilizers to the underbody panels as well. I can easily rivit or weld on a few of these guys for some extra air stabilization:


I have a feeling the benefit of the panels will be much improved with the stabilizers. Ultimately they will stretch from the back of the front wheels (probably) all the way back to the connection with my eventual diffuser.

I would like to be able to add front and side splitters at some point too, but the front splitter would be a track-day only feature due to how low the front lip is...
 

·
Registered
Joined
·
899 Posts
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Hawkeyes man :naughty:

If I ever crash mine I'll put the Hawkeye front on it :D

Love the wheels, bet they look awesome on rolling shots!
The whole car is :cool::tup:
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #326
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Hawkeyes man :naughty:

If I ever crash mine I'll put the Hawkeye front on it :D

Love the wheels, bet they look awesome on rolling shots!
The whole car is :cool::tup:
Thanks man! I've been wanting to do a rolling shoot forever but I havent been able to line one up yet... I'll get there one day (although probably not as cool as your shots at hockenheimring... haha)
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #328 (Edited)
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Heres the phase 2 panels welded up. Still need to drill the mounting holes, then I'm going to add the air stabilizer fin things... I'm not sure what they are called.


 

·
Registered
Joined
·
899 Posts
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Nice!
How much does it weight compared to your previous ABS version & in total?
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #330
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

i haven't' weight it yet since I still need to add the fins (whatevertheyarecalled) but I'm anticipating the wieight to be close but a little less. The aluminum by itself is both lighter and more rigid. FTW!
 

·
Registered
Joined
·
899 Posts
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Yeah I don't expect it to be heavier than the ABS.
I was just curious.

Total weight would still be interesting :)
I like the idea of closing the underbody.
Wondering if there would be any benefit in terms of Aero out on the Track.
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #332
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

there should certainly be a benefit, but exactly how much of one is unclear. I'd need a wind tunnel for that...

My goal of a complete flat bottom car and rear diffuser should lower drag under the car, as well as help to create stable low pressure air to increase downforce (technically its "reduce lift"). As with all aerodynamics, air speed over the surface plays a huge part, so I doubt much will happen outside of a track besides potentially seeing incremental gains in MPG around town...
 

·
Registered
Joined
·
899 Posts
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

It really is a interesting approach and I think worth looking into! Glad you're doing the pioneers work here :)

What plans do you have for a diffuser?
Building one on your own or spending the money on available Products on the market?
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #334
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

I had planned on buying one, but Ive started leaning towards building one now. Considering how much cheaper it would be and that I could make it exactly how I wanted... I just have to figure out how I would install it first, and then I can start planning it out. I am very seriously considering building my own (out of aluminum). It won't be big and crazy like a time-attack car though, it will still be smallish, like the Mature or HKS/Kansai diffusers.

mature:


hks/kansai:
 

·
Registered
Joined
·
899 Posts
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Yeah the Prices are kind a out of this world for carbon parts. And even more expensive to have them shipped to Germany :eek:

And it's a part that only looks good for the first time mounting it. Taking the car out for a drive and it's going down from then on. That's why I'm not a fan of carbon parts. Expensive to replace. Sure they are light but only worth to those who like spending the money on them.
So the DIY solution seems much more likely for me too.
And there's no need for a huge diffuser on our cars.
It's legit when building a full Track car like funk32 does but going too crazy on a non widebody, daily driven car is not very pratical from my point of view.

The HKS/Kansai would be my option for sure! (Using it as a reference for the selfmade one so to say) Best looking one imho :tup:
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #336
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Yeah I like the HKS one a lot, but you have to cut off part of the bumper to fit it :(

And i agree on the carbon completely! I was actually planning on the plastic equivalent but even that is like $700-$800 shipped for the HKS and way more for the Mature...
 

·
Registered
Joined
·
899 Posts
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

If you build it by yourself, just skip the part with the bumper cutting and make it fit without the need to cut. Will still look nice! :)

I ordered the DEI Gold Heat wrap: Project NASA Engine Bay will start this weekend :D
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #338 (Edited)
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Been working on the underbody panels today and finished the drivers side panel. (Although i may add fins to that one blank section in front... Not sure).





Im so glad I went with aluminum, this is SO much better!
 

·
Premium Member
Joined
·
2,612 Posts
Discussion Starter #339 (Edited)
Re: BlueScooby's 06 STI - Underbody Panels (Phase 2) Revisited...

Finished and installed the phase 2 aluminum panels!

Completed:


Installed:


With the addition of the fins the weight of the aluminum panels is about the same as the plastic panels. In total, 10lbs (about the weight of a gallon of water...) for the phase 2 aluminum panels; which isnt bad considering it's basically a 6'x3' sheet of metal with some extra bits... And now they are completely rigid rather than floppy plastic :tup:
 
321 - 340 of 1193 Posts
Top