brake ducts
- Thread starter gt40man
- Start date
AlohaGT
GT Owner
Though this thread has tendency to wander off topic a bit, I think you'll find it helpful.
http://www.fordgtforum.com/forums/showthread.php?t=1027&highlight=front+brake+ducts
cobrar1339
GT Owner
The short anwser is one side will plumb easy enough.
The other side has the AC condenser lines in the way. From the posts I have read, you have to have these lines custom built to work around them.
You may find it interesting that the Matech car no longer has a visible brake duct. There has been an evolution of sorts on the front nose of those cars.
Speaking with the engineers at the Rally, opening the duct was NOT advised for very high speed runs. For track days it should be fine. But in there opinion it was not needed. Brakes were not an issue in testing.
The other side has the AC condenser lines in the way. From the posts I have read, you have to have these lines custom built to work around them.
You may find it interesting that the Matech car no longer has a visible brake duct. There has been an evolution of sorts on the front nose of those cars.
Speaking with the engineers at the Rally, opening the duct was NOT advised for very high speed runs. For track days it should be fine. But in there opinion it was not needed. Brakes were not an issue in testing.
Indy GT
Yea, I got one...too
Engineers also pointed out opening up these ducts (and routing flow to brakes) INCREASES aero drag on the car ie slows the car down in high-speed regime. They advise not to do this. The brakes do just fine.
Brake testing during certification for our cars "excellent" rating (standard FGT Brembo's) had the car make a full ABS stop from 80% Vmax (164mph) with immediate accel to 60mph (3.3sec) and another full ABS stop, repeated nine more times without any cool down period in between accel/decel cycles. Last two stops of the 0-60-0 were the shortest of all stops.
Who honestly can say they really have any brake fade problems.....
Again, give Fred's team credit for building our car right.
Brake testing during certification for our cars "excellent" rating (standard FGT Brembo's) had the car make a full ABS stop from 80% Vmax (164mph) with immediate accel to 60mph (3.3sec) and another full ABS stop, repeated nine more times without any cool down period in between accel/decel cycles. Last two stops of the 0-60-0 were the shortest of all stops.
Who honestly can say they really have any brake fade problems.....
Again, give Fred's team credit for building our car right.
As one who has functional brake ducts, see pictures and other threads, totally disagree with the fact that the stock brakes work just fine. Easy to go through a set of pads in less than a day at the track. Airflow helps them last the full day. Brake fade and brake wear are two seperate issues that exist on the track.
The amount of drag created by openign the ducts is not important or noticeable.
Brembo offers special brakes, big bucks, to help with the situation.
Brakes may be fine for street but not for the track.
Dave
Fubar
Totally ****** Up
The problem with opening the ducts happens at higher speeds.
The way I understand it... the designers used diffusers at the front of the car (much like the back section) to create down force. Opening ducts to the front wheel well (and thereby adding a lot of air pressure there) reduces the ability of the front diffuser to create a vacuum (down force). These diffuser are moving air into the brake area; probably not as well as the ducts would but I don't know?
It has more to do with creating down force than reducing drag.
The way I understand it... the designers used diffusers at the front of the car (much like the back section) to create down force. Opening ducts to the front wheel well (and thereby adding a lot of air pressure there) reduces the ability of the front diffuser to create a vacuum (down force). These diffuser are moving air into the brake area; probably not as well as the ducts would but I don't know?
It has more to do with creating down force than reducing drag.
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BlackICE
GT Owner
Baronw, so do I understand correctly, the stock brakes stop fine, but the pad life is too short to last a day of aggressive track driving and the ducts aid in pad life.
Blackice
Yes.
We have beat this to death in other threads.
Also who ever started the thread should have done a simple search to find the other threads with all the same information including the red herring of drag resistance if you open the brake ducts.
Dave
Indy GT
Yea, I got one...too
Data Speak
Dave you are correct, this topic has been discussed at length in other threads...
I appreciate your technical comments as many others do as well. They are generally well founded. But to summarily dismiss the engineering data collected by the design team as they worked thru the aerodynamics of our cars as a "red herring" is a bit much.
As a technical appreciative individual, I hardly see why you dismiss the data collected. The data speaks for itself... (drag increases, whether you can "feel" it on the track or not).
Dave you are correct, this topic has been discussed at length in other threads...
I appreciate your technical comments as many others do as well. They are generally well founded. But to summarily dismiss the engineering data collected by the design team as they worked thru the aerodynamics of our cars as a "red herring" is a bit much.
As a technical appreciative individual, I hardly see why you dismiss the data collected. The data speaks for itself... (drag increases, whether you can "feel" it on the track or not).
Everyone can have their own opinions and beliefs which is what makes a forum of interest. But to assume that some one "summarily dismiss" is a bit of a strech without knowing the resources that individual has researched and has available before they make a decision.
Also while the design team did a nice job not everything that was done is perfect nor did the budget allow some items to be finalized and installed. That is not a criticism but a statement of fact. The car was late to market.
As mentioned before we are not doing a land speed effort at Bonneville where aerodynamics is super critical. So the increased drag of open ducts is relatively meaningless for the type of DE that people on the forum do. Doing 165-170 mph down the back strech at Watkins Glen is fast, closing the ducts would not help. Open ducts with proper ducting provide better braking which I find is more critical than adding speed on a straight-away.
Dave:cheers