[VA STI]

That setup looks amazing. Did you DIY the vents?

 

[joshua@arcflashllc]

That setup looks amazing. Did you DIY the vents?

Yes, but we're a shop and I've been doing motorsports fabrication for over 20 years... It's not exactly DIY

 

[TX STIG]

...(i think partly that is due to me trying to keep up to a 2018 zr1 corvette which i did, but i think it was due to the driver of the corvette)...

:lol: ya think?

 

[steve.schlos]

check out the boomba brake cooling flaps. After my first track day where I might as well have been without brakes, I did those flaps, removed my rotor dust shields, steel brake lines, RBF600 fluid, and G LOC R10 front/R8 Rear pads...SUUUUUUUCH a huge difference. Second time around the brakes didn't fade at all and definitely got the car stopped. Now I'm struggling with oil heating, even with a mishimoto 19 row cooler.


Going back to the track tomorrow!

 

[white STI type RA]

as a race engineer and having worked for a number of race teams over the years and testing brake temps with and with out the brakes backing plates in place or not. every car we tested had lower brake temps with a backing plate. we found out why is that your vented rotors is like a fan blade drawing air in from the center and blowing it thru the rotor vanes and out the top. with the backing plates removed the air will not get forced thru the rotors vanes as much as it does with the backing plates in place. i will add i have never tested this on a STI but with Paul newmans vett and his camaro GT1 cars and VW rallygolf rally car and our porsche 944's and gt3 cup car they all ran lower brake temps with the backing plates installed.

 

[yamahaSHO]

Are you talking about the dust shields? That's pretty common knowledge to remove them if they are not funneling in air by design.

 

[white STI type RA]

yes most all backing plates are designed to duct in thru the rotor vanes.
most people do not take there brake temps. hell most don't even take there tire temps!
most every one just assumes that the backing plates hold in heat when in fact if you really take brake temps you will find in most all cases they do not.
a vented rotor is a fan like any other fan it has to have air drawn in for it to work.
this is why i would guess places like subie speed offers there brake cooling backing plate kits with the plates.
like i said having worked for some IMSA teams and others we have tested and found you will get cooler brake temps ( in the cars we tested) if you keep the backing plates installed.
also like i said i have not tested any of the STI's to have data from them.
if you have real temps and data i would love to see it on the STI's.

 

[yamahaSHO]

I'll have to take a picture of my track car. Dust shields are removed, but I have plates mounted the extend out to the ID of the rotor and feed 100% of the ducted air through the rotor vanes.

On every car I have tracked, (yes, I took temp readings) OEM dust shields made the rotor temps hotter. On the S2000 boards, a guy recently posted heat issues with having dust shields in place with brake ducting... We told him to remove and no more heat issues. We also had a thread where they tested both sides of the rotor and the inside was significantly higher with the shields.

 

[white STI type RA]

what are the temps??
before and after .
at what tracks? and what were the track temps of each day?
what pyrometer was used?
as i'm sure you know a laser type pyrometer is totally useless so if it was used the data is worthless.
a brake pyrometer is the only way to take real brake temps.

 

[yamahaSHO]

what are the temps??
before and after .
at what tracks? and what were the track temps of each day?
what pyrometer was used?
as i'm sure you know a laser type pyrometer is totally useless so if it was used the data is worthless.
a brake pyrometer is the only way to take real brake temps.

I do not recall the temps anymore... we did most of our testing years ago. What tracks? Every track we used the brakes on.

Although I agree that a laser type isn't the best, it's not totally useless in the right hands, but it's not what I would rely on for making the most accurate measurements.

Most OEM dust shields don't really funnel a while lot of air in, especially under the lower pressure of the air under the car. Additionally, I've had a dust shield equipped car eat inner pads far quicker than the outboard pads, no temp reading needed. Also, no readings are needed when you cook a pad with shields and get fade, to getting now fade after removing said shields... Been there too.

Pictures of my car as spoken about in the last post.

These alone do no real funneling of air into the center of the rotor for the air to be pumped out. It's a low pressure zone in addition, the air in front of the wheel is being blocked and pushed around the area. The wheel well liners keep the higher pressure air from the front of the car from being funneled through as well.

Funny comment on people not taking tire temps... Many of the really fast guys (and I mean REALLY fast) I know don't bother (and they build their own cars - except when one of them races professionally). And they've gone on to really high levels motorsports and OEM's. So... I don't take tire temps, but I seem to be able to get the cars setup competitive anyway.

 

[white STI type RA]

funny your running backing plates with your air ducting.
as we now don't stick our tires with a probe sensors any more and haven't for many years the same for tire pressures and brake temps.
in IMSA now we all do it with on board real time telemetry it's so low cost now we even do it with our glass roots racing cars also.
i'm still not seeing any real data nor any proof with the STI's that removing the back plates will drop your temps one bit.
every thing is so vague invalid and undocumented my self or any other engineer will just take your some ones word on it.
adding a duct with a backing plate should drop brake temps but just removing the backing plate and adding no ducting i'm still wondering about that one.
if you would like to talk about air flow and pressures to a me ( i'm a aerodynamicist that was the 1st degree i got and what i went to school for then chassis and suspension) i'm all for it.

 

[yamahaSHO]

My plates are a bit different than the stock ones you were speaking about... Not quite the same argument.

I have a good friend who is an aerodynamicist as well. He just built me a wing and splitter for my track car. I like having conversations with him when it comes to me designing things for my usage. His twin brother is on the Porsche race team as well.

 

[stiprince]

so i finally had my track event last week.

installed stainless steel brake lines
changed my brake fluid with fresh dot4
flushed out my coolant with new fresh coolant

and the results were;
the car did run a lot cooler, ran about 210f throughout the day, so i am very happy with that.
the brake pedal feel was great with the stainless steel lines. oh wow was that a nice treat to have, what a big difference that made swapping them over, so no i did not have any brake fade or brake pressure loss during the day.

but i did have a new issue arise just before my day was over. i did notice during the last few laps that my brakes were making some weird grinding noise (could hear specifically the front right). didn't think much of it, so i finished my time on track and when i went to the pits and went to park i noticed that there was quite a bit of smoke coming from my right front wheel. went out and checked it out and my brakes were smoking/catching on fire. so i got a fire extinguisher and put it out....i later checked the pads and they still had life left in them so no metal to metal contact....don't know what could have cause this and why?

 

[8cd03gro]

as a race engineer and having worked for a number of race teams over the years and testing brake temps with and with out the brakes backing plates in place or not. every car we tested had lower brake temps with a backing plate. we found out why is that your vented rotors is like a fan blade drawing air in from the center and blowing it thru the rotor vanes and out the top. with the backing plates removed the air will not get forced thru the rotors vanes as much as it does with the backing plates in place. i will add i have never tested this on a STI but with Paul newmans vett and his camaro GT1 cars and VW rallygolf rally car and our porsche 944's and gt3 cup car they all ran lower brake temps with the backing plates installed.

What air is being forced into the center of the disc by the backing plates? Air from where? At least on the GD, the dust shields have no vents. They are literally as close to 100% coverage outside of the caliper as they could get, with a lip that wraps around slightly on the outer edge. I'm not experienced in aero so I'm more asking than telling, but I don't see how this could be beneficial for airflow to the center of the rotor.

 

[white STI type RA]

What air is being forced into the center of the disc by the backing plates? Air from where? At least on the GD, the dust shields have no vents. They are literally as close to 100% coverage outside of the caliper as they could get, with a lip that wraps around slightly on the outer edge. I'm not experienced in aero so I'm more asking than telling, but I don't see how this could be beneficial for airflow to the center of the rotor.

Image Link

a rear parking brake ?
the rears on many cars tend not to have the holes in the backing plates for vented rotors.
many front backing plates do tend to have the holes in the backing plates to aid in ducting air into the vanes of the rotors.
a vane rotor is essentially a fan it draws in air from the center and pushes it out the top of the rotor as it is spinning. like removing a shroud from just about any fan it will make the fan much less efficient.

 

[white STI type RA]

at no time have i said WITH THE STI's that you will not get cooler brake temps if you do not remove the backing plates.
i am looking for real data with temps that is all no one has given any really data on this for the STI's.
no one has taken there temps to know not by pyrometer not by thermochomic paints and not by temp strips.
as a race engineer i'm looking at this as if you remove the backing plates you will drop your temps down and have no more problems and this may not be the case.
depending on what brakes your using and how hot or cold they are working you may not be getting the most out of your braking system.
a brake that is not getting up to temp will not give you the best braking you can have. simply because your not over heating your brakes in no way means your getting every bit from them.
for a street pad they tend to work from 100 to 650 degrees F .
for a street /track aka sport pad they tend to work from 400 to 1000 degrees F.
for a race pad they tend to work from 600 to 1500 degrees F.
if your working no on the lower end of the temp range then your not getting all you can out of your brakes.
guessing is not getting you better braking. this is all i'm saying.
with no real data and some guys just saying on some on line forum that i know nothing about were they race there classing of car there finishes and so on i sure will not take there word for just do this and now every thing is good.
when you look a race STI and they have a backing plate in place and we run them on all our race cars in every thing from AER to LMP challenge because we do take and know our temps of each event of each day the cars are on track.
this hole discussion is really very pointless.

 

[8cd03gro]

Both of those cars have ducting...

 

[clapanse]

Backing plates with air ducting can be a fantastic thing, since it forces a large amount of air within close proximity of the disk, and also enforces a high shear rate in the boundary layer, encouraging heat transport off the disk surface (convection is more effective with a thin, high-shear boundary layer). This is very different from backing plates without air ducts, which I would bet nearly universally increase rotor temperature.

 

[white STI type RA]

the owner of this car was not having over heating problems he like so many others removed his backing plates in the thinking he would drop his brake temps down more.
his next two events ( the glen and NJMP ) he over heated his brakes and started cooking his balljoint boot.
i had some extra ducting so just put that on to get him thru the rest of the NJ event.
still no backing plate and his brake temps were still on the high side 1100F for the race pads he was running.
I HAVE SENSE MADE HIM ALUMINUM BACKING PLATES and painted the rotor vanes with thermochromic paint he is now running temps in the sweet spot of his brakes he's using about 850F average.
once again with out any data on the STI just removing a backing plate may not drop your brake temps. it also may but with out any data it's just a guess.
on the few cars we have just removed the backing plates from it did not lower the temps at all.



edit the photo doesn't seam to load.

 

[clapanse]

I completely believe you could have balljoint heat issues after removing the backing plates, since they will act as heat shields and protect the suspension from experiencing the brake heat as directly. However, I have a very hard time believing that the rotor temperatures dropped by 300F unless there's some kind of air scoop or duct incorporated in the plates you're talking about. I'd be curious to see the photo, but I feel pretty confident in the general statement that backing plates will nearly always increase rotor temperatures unless they incorporate some kind of forced air mechanism.