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Discussion Starter · #1 ·
I have a stock 1990 Z51 that I road race. Both my dad and I drive this car at NCCC time trials. We seem to have a problem with brake fade. With both of us driving it it never really gets a chance to cool down a lot before the next person has to take it out again. Since we have to engine or power mods the stock brakes are plenty for what we are doing, but they get too hot for our liking. Is there an inexpensive alternative?

Thanks
 

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DC Crew
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How about cutting the lower air dam and put some homemade piping to the brakes to get cool air on them while driving? Something like the Z06's use.
 

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Couple people I know have used this to help.....looks pretty cool too.....
http://www.mamotorworks.com/corvette.html?frame=1.3979
The MAM 603-657 (1984-90) fits well on an '89. It serves well for basic cooling
requirements, more cooling is required for severe usage.

The 2.5" duct supplied with the spoiler is a poly material that won't stand up
long to heat. Pegasus offers better quality replacement hose rated for
higher temperatures.

I am not sure whether he is active on DC, but a racer offers hub mount
inlets that serve as hose attachment points and help direct air into the
center of the rotor.

.
 

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The MAM 603-657 (1984-90) fits well on an '89. It serves well for basic cooling
requirements, more cooling is required for severe usage.

The 2.5" duct supplied with the spoiler is a poly material that won't stand up
long to heat. Pegasus offers better quality replacement hose rated for
higher temperatures.

I am not sure whether he is active on DC, but a racer offers hub mount
inlets that serve as hose attachment points and help direct air into the
center of the rotor.

.
:agree: I have that kit as well. The lower spoiler on my car was in poor shape or I would have just put the naca ducts in. The hose did melt at the end, I sprayed it with high temp paint in hopes that it would reflect some heat. If more of the hose melts I'll have to use the good high temp hose. I have to tie the hose back after a track event or the tires will rub holes in it. I swap out the track pads, inspect the brakes, and slightly reroute the hose.

I like the Carbotech pads. I burned through some sets of semi met pads that really made a mess and switched.
 

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I run stock equipment pads and rotors.

I like the way these spoilers look. Any suggestions on how to keep the hose from melting?

Thanks guys. :thumbsup:
I'd strongly suggest changing your pads to a compound better suited to track use and possibly even adding slotted rotors if that is an option. High temp fluid is also a must if you aren't already running it. As well as trying to cool your brakes, you also need to ensure that your braking hardware can cope with the higher temperature of trackwork and prevent the fluid from boiling (as opposed to the lower general temps in normal highway use). All of these components work together. :cheers:

Changing the pads on my 90 Z51 made a big difference not just to fade but pedal feel and stopping ability. I'll refrain from suggesting a pad though as I'm yet to find one I'm really happy with, but will be trying a wilwood pad next based on an advisory and ride in a friends Z06 - I just haven't chosen the compound.

edit: I just reread your original post and noticed the need for a budget solution.

I'd see if upgraded pads and fluid are in the budget. As far as the cooling ducts go, I made my own inlets in the front spoiler with pvc pipe from the hardware store (I am still rigging up the rest of the pipework). If you are handy with basic tools and can improvise you can put that $150 in your pocket and buy the parts for less and make your own cool air ducts.
 

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you also may want to totally flush and replace ALL the brake fluid with new dot 4 or dot 5 (depends on the car, year, and type of set up) DON,T MIX
as a small amount of moisture mixed in the fluid (and some types absorb moisture from air)will cause a good deal of fade as it tends to turn to steam under high loads/temps, if the fluid in your master cylinder resevoir looks dark and cloudy its probably got some moisture in it:thumbsup:

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

http://www.classicperform.com/TechBook/BrakeTroubleshoot.htm

BTW DOT 5 won,t mix with dot 3-4 and generally is a P.I.T.A. to use, its silicone base rather than glycol/ester based like dot 3-4
 

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Discussion Starter · #12 ·
you also may want to totally flush and replace ALL the brake fluid with new dot 4 or dot 5 (depends on the car, year, and type of set up) DON,T MIX
as a small amount of moisture mixed in the fluid (and some types absorb moisture from air)will cause a good deal of fade as it tends to turn to steam under high loads/temps, if the fluid in your master cylinder resevoir looks dark and cloudy its probably got some moisture in it:thumbsup:
It has brand new DOT 5 Valvoline synthetic fluid in it. The system was flushed before the track day. I am pretty good at making things seeing as I am always on a budget when it comes to racing. As far as pads go I could look into that IF they are not too radically priced. Any suggestions on brand names/compounds to look into?
 

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Any suggestions on how to keep the hose from melting?
As mentioned above, replace it with better quality high temp silicon air duct.

This is available from Pegasus in various diameters and lengths. Because it
is a consumable item, buy lengths that are multiples of what are required so
that you have spares on hand.

As The Dingo wrote, a DIY solution is a possiblity for some. There have been
folks who used PVC rain gutter components from Home Depot to create
inlets at the spoiler that fed lengths downspout material and then flexible
dryer duct out to the hub. At least one instance consisted of multiple
gutter inlets feeding a common duct for greater intended air flow.

An intermediate alternative might be to buy purpose-built inlets and silicon
air duct from Pegasus and integrate these into the OEM spoiler.

About brake fluid: 'Valvoline SynPower' is readily available, well regarded and
modestly priced.



Speed Bleeders will make it easier to bleed the fluid. Bleeding should be done
at least annually - if the colour/clarity of (non-dyed) BF more closely
resembles coffee than apple juice, it is overdue for bleeding.

Russell Performance offers/offered a copy of the Speed Bleeder and in the
past, there were unfavorable remarks about these. I see now that Russell's
site promotes "Speed Bleeder®" - either they now carry the originals or some
Intellectual Property wizard has secured the rights to the name for Russell.

.
 

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BTW DOT 5 won't mix with dot 3-4 and generally is a P.I.T.A. to use,
its silicone base rather than glycol/ester based like dot 3-4
I agree. DOT 5 fluid is less than ideal.

The Valvoline SynPower is DOT 4 and my vote is that it is compatible with
other DOT 3 & 4 fluids.

.
 

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Discussion Starter · #16 ·
I agree. DOT 5 fluid is less than ideal.

The Valvoline SynPower is DOT 4 and my vote is that it is compatible with
other DOT 3 & 4 fluids.

.
I currently use the Valvoline SynPower and like it a lot. Its great for the money.
 

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With both of us driving it it never really gets a chance to cool down
a lot before the next person has to take it out again.
If you think that more cooling between rounds would suffice and if you
have a generator with you (trailer/motorhome), then an option is to use a
contractor's blower fan. This would not only help cool the brakes
but would also bring down engine and transmission temperatures.

The Stanley #655702 is cheap at W-M ($34) but it vents high.



The Blue Blower vents low. Depending on how much current capacity is
available, it is available in 1200 CFM (PB1200 - $130) and 2500 CFM
(PB2500 - $190) versions.



.
 

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Ok, running two drivers with stock pads is your main problem.

First thing I would do is invest in some Carbotech pads at least for the front (but ideally front and rear). I can not express to you in words how much of a difference Carbotech pads will make, they will take the heat, and will inspire braking confidence that you have never had, you will get good life out of them and you can drive them on the street if desired (a bit squeaky and dusty though- but not corrosive).

Here is their website: http://www.ctbrakes.com/

Here is a link from Stoptech about brake fluids, I personally would step up to a higher temp brake fluid (every bit counts) considering you have 2 drivers, I and all my race friends run ATE Superblue.

http://www.stoptech.com/tech_info/wp_brakefluid_1a.shtml

Brake ducts are a great idea as well, but are going to fix your main issue.
 
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