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Discussion Starter #1
Hi,

Are Turbine covers effective as BMW claims ? They are saying it does better cooling with about 25% more compare to regular.

Turbine Covers cooling vs Throwing stars, they are more open ?

Anri
 

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I can only tell you this Anri :

A friend and I did a track day . He had Throwing Star covers and I had Turbines .

We completed 5 laps together before pulling into the pits .

Without the use of specialised temperature recording equipment , I put my hand on his front discs and he put his hand on my front discs .

We both got burnt , although I'm sure that my burns were worse than his !

Hope this helps !

D
 

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Discussion Starter #3
Dave,

So you mean that their is not much difference between both sets, you felt more heat on his wheels ? I hope I did understand you.

I mean I am not expecting huuuuge difference, but I think your hand test was not exact because you must use the laser temp tool to show the exact difference.

A
 

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true david, your friends heat tolerance levels might be greater than yours resulting in your scientific testbeing inconclusie,,,,:)

as for the original question,,

if the turbines are that much better why did BMW change them? i got to admit they do look great but so do the throwing stars, not a patch on the M Pars!

now fuse is lit i will stand back
 

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I think both systems were engineered to function in a way that will aid in cooling the brakes, not sure that one is "better" than the other, rather they work slightly different. On my car, there are 2 functioning brake ducts in the lower bumper that directs air to the backside of the brakes and the T-Stars suck that air out keeping things cooler and eliminating much of if not all brake fade. The turbines act like a fan and pull air in toward the brakes thus cooling things off from that perspective. I think both are equal in function.
 

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true david, your friends heat tolerance levels might be greater than yours resulting in your scientific testbeing inconclusie,,,,:)

as for the original question,,

if the turbines are that much better why did BMW change them? i got to admit they do look great but so do the throwing stars, not a patch on the M Pars!

now fuse is lit i will stand back
M Pars better than Turbines or Throwing Stars!!!!! Have you gone mad Steve? ;)

TBH if your really concerned about brake fade on the road then try some different pads or fit a BBK. I dont think there is that much in it between the two types from a function point of view.
 

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Discussion Starter #7
Thanks for all reply.

Turbine covers import air to the brake rotors. Throwing stars takes the air out. So I guess they are very equal.

Anri
 

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to work with brake ducts, go with TStars.... to keep OEM cooling, choose for you taste...
 

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to work with brake ducts, go with TStars.... to keep OEM cooling, choose for you taste...
 

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Discussion Starter #10
Actually now I am thinking that the T-Starts are absolute effective because after I clean the wheels along with my car. After a few day of driving my wheels are dirty black on the lip.

With turbine covers my wheels never gets black, because they import the air.

May be the benefit of using the is not to clean the wheels that ofter :hihi:

Anri
 

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One option might be slightly more effective than the other but lets be honest,
if you're after maximum braking performance you simply throw away the standard
set up and start somewhere else don't you ?

I love my car (and it's completely standard).
I don't track the car anymore but when I did I could quite easily reduce
the standard brakes to mush in three laps.

At no point did I ponder which wheel fan would improve the fade resistance,
I simply knew that I was driving a heavy, fast, road machine on a track.

Put the covers you really want on your car,
the ones you like best :)

If you want to improve the brakes overall, change the brakes !


Regards,

Alan.
 

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Actually now I am thinking that the T-Starts are absolute effective because after I clean the wheels along with my car. After a few day of driving my wheels are dirty black on the lip.

With turbine covers my wheels never gets black, because they import the air.

May be the benefit of using the is not to clean the wheels that ofter :hihi:

Anri
my turbines get very dirty with brake dust, especially the outer lip, so i'm not sure if that is a good way to gauge their cooling abilties.

As to why bmw changed them? the press hated them, and when dirty they made the car look like it was wearing 'white wall' tires.
 

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Discussion Starter #13
One option might be slightly more effective than the other but lets be honest,
if you're after maximum braking performance you simply throw away the standard
set up and start somewhere else don't you ?

I love my car (and it's completely standard).
I don't track the car anymore but when I did I could quite easily reduce
the standard brakes to mush in three laps.

At no point did I ponder which wheel fan would improve the fade resistance,
I simply knew that I was driving a heavy, fast, road machine on a track.

Put the covers you really want on your car,
the ones you like best :)

If you want to improve the brakes overall, change the brakes !


Regards,

Alan.
For now I will run 850Ci Brakes 325x30, Rear 300mm vented from E34 M5. Car is E24 M6 lighten to around 2700pounds. That is just 1000pounds lighter than standard stock E34 M5.

The reason started this threat is because I like both sets. But since they are even, I guess I will keep the T-Stars.

Anri
 

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I read the Turbines are better but, yes got bad press for looking tame - like plastic wheel covers on white walls. Of course they look much better now, intricately complicated. I thought the fans draw air in the middle which passes through the brakes and is then expelled under centrifugal force via the outer part?

Having once picked one up the Turbines seem very heavy for a wheel cover, and given the importance of unsprung weight I concluded BMW must have thought the braking benefit worth the penalty!
 

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Bwahahahaha @ David. Really scientific. hehe

What I don’t understand is why the turbines suck air into the wheel well.
Isn’t the wheel arch/well a high pressure point at speed and therefore the high pressure generated at speed that tries to escape will fight/clash with the turbines trying to force air in???
In that respect I think the System II covers are better in that they suck hot air out.
I think that the turbines would work better if they were reversed. Any comments on that??
 

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I measured the brake-temp on a few M5's during a visit to the Nordschleife in October 2002; now more then eight years ago; I posted the results on the mailing list from which I quote:

raymondw on the E34 M5 mailinglist (message 22100) said:
@Finn,

I hope you arrived not too early monday morning. almost 2k km on a single day.
Ouch. When I drove home yesterday evening, I was tired so I did not go over
180km/h. If any of us needs to improve the brakes, it is you. My laser
temperature meter has a range to 500 degrees Celcius, but this was not enough to
measure your front brake temp. Your rear brakes where around 140 degrees
Celcius. I should have measured your brake temps after your cooling down also.

Just a moment before, Stevie and I measured the brake disk temperature of the
Winckelhock E34 M5 that was driven privately by one of the fahrsicherheits
instructors. His temperature readings showd 400 degrees Celcius on front disks
and 100 degrees Celcius for the rear. This was measured only 30secs after he
came of the track. Although not a valid comparison, we can conclude that the
turbine rims provide for better cooling of the brakes.

Just for the record:

E34 M5 #1 (FRONT: 260, REAR 60) (Raymond's E34 M5 with throwing stars)
(Measured after cooling down)
E34 M5 #2 (FRONT: 320, REAR 100) (Serge's E34 M5 with throwing stars)
(Measured after cooling down)
E34 M5 #3 (FRONT: 400, REAR 100) (E34 M5 Winckelhock with turbines)
(Measured 30sec after it came of the track)
E34 M5 #4 (FRONT: >500, REAR 140) (Obviously Finn's E34 M5 with throwing
stars) (Measured 30sec after it came of the track)
 

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Thanks Raymond, now I know why rear brakes are so long lasting and don't need ducting.

Bwahahahaha @ David. Really scientific. hehe

What I don’t understand is why the turbines suck air into the wheel well.
Isn’t the wheel arch/well a high pressure point at speed and therefore the high pressure generated at speed that tries to escape will fight/clash with the turbines trying to force air in???
Would need to look again closely at the cover but centre is like a rotating impellor that draws air in due to rotation. This then circulates around hub and brake before the rotation of the vanes in the disc sends the heated air outwards to be drawn out of the wheel at the outer edge... My assumption anyway.

There is very little other cool air supply to the brakes on the E34 M5 - the alternator stakes a bigger claim to the cooling duct in the spoiler! Even my E36 328i SE Coupe had brake cooling air ducted through the bumper.

It is true that the air in wheelarches tends to be higher pressure, in part due to the rotation of the wheel as well as relative stasis, and this is a source of lift in cars. Whether the T-stars actually evacuate the air from around the wheel is probably very debatable. However the dust patterns on the rims suggest they do assist in the outward movement of air from the brakes to some degree. Of course the M-Pars do not.
 

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In that respect I think the System II covers are better in that they suck hot air out.
I think that the turbines would work better if they were reversed. Any comments on that??
frank fahey of fahey motorsports, a souther california bmw shop, felt the same way. Not sure if he had any data to prove it though.

Personally, i'd believe in the engineers at bmw motorsport and mount them the correct way.
 

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I think that the Axial flow on the turbine covers will definitely be far more than the flow generated by the throwing stars at the same rpms <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
 
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