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Discussion Starter #1
I'm open to suggestions on reducing drag on maverick/granada front disc brakes. it is not a stuck caliper I'm just looking to reduce the rolling resistance I think it is effecting my consistency at the track
 

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Some master cylinders have residual pressure valves within them. You have to remove the port seat (where the lines fasten) on the master cylinder to remove them. Not sure if you can punch it out without removing the seat.
 

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You can turn the rotors to the miniumn thickness or thinner and decrease drag.One word of caution,this can be dangerous,only for racing and not for heavy brake pressures.
 

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I would advise against turning the rotors any more than needed to true them.

The method of operation of the disc brakes and calipers is such that as the rotor and pads wear, the residual pressure of the brakes prevents the piston in the calipers from retracting the pads more than necesary to allow free-wheeling of the rotors. Most people would be very upset if the system allowed the piston to retract fully as the pads wore down and they had to pump the brake pedal to stop. Therefore, unless you remove the residual pressure, the calipers/pads will not fully retract no matter how much you decrease the thickness of the rotors.

Brake systems with the master cylinders mounted higher than the calipers aren't as prone to the piston retracting an excessive amount as with the master cylinder mounted lower than the caliper.

Not sure if you can find them, but if you could replace the o-rings in the caiplers with round o-rings instead of square cut o-rings, they should retract more and quicker (less surface tension with the round 0-ring)
 

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The old racers would convert to drums. In fact my 428SCJ had been converted by a previous owner from factory disks to drums due to the drag.
In today's world though, properly functioning disks where the (single piston) caliper moves freely in its bracket and the fluid is moving unrestricted back into the reservoir, you shouldn't be getting so much drag that it would cause inconsistent ETs. When I ran my company car at Famoso (4w disks) it ran super consistent times. Slow (16.10s), but very consistent.
 

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The old racers would convert to drums. In fact my 428SCJ had been converted by a previous owner from factory disks to drums due to the drag.
In today's world though, properly functioning disks where the (single piston) caliper moves freely in its bracket and the fluid is moving unrestricted back into the reservoir, you shouldn't be getting so much drag that it would cause inconsistent ETs. When I ran my company car at Famoso (4w disks) it ran super consistent times. Slow (16.10s), but very consistent.
 

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If you had enough contact of pad and disc while the brakes were not being operated to affect ET's, youre discs would be hot as hell during normal driving.
If you want to check... find a loooong road, get up to 60 and roll to a stop or gently handbrake it.
If you have drag you will feel a LOT of heat from front wheels.
 

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I have an old car craft article on a 65 mustang GT drag car. He swapped the single resevoir master cylinder to a dual one to reduce residual pressure but unfortunately it doesn't say what master cylinder he used.The car dropped from a 12.60 at 106 to a 12.10 at 110 mph.
 

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Kenny see 69 parts i.d. in this same forum for an interesting factoid that may apply to you
 

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Discussion Starter #10
Thanks for all your imput. It turns out that the caliper slide need some attention. cleaned and lubed the slides and went tothe track last night ran 5 passes within a 5 hudredths of each other. track left a little to be desired most of my e.t. change was in the 60ft.
 
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