Suspension and Brake upgrade advice needed

[Randy C]

I drive an '86 LX convertible with a '69 351 Windsor, bored 0.030, Mass Air conversion and Trickflow induction and heads. I bought the car new and started modifying it in 1992. Modifications: '87 front struts conversion with red Konis front and rear; K-member from an '88 GT, with welded seams and slotted bolt holes to allow moving it forward about an inch; front lower control arms from a Turbo Bird; Maximum Motorsports caster/camber plates; rear Griggs weight jacker control arms; front coil overs; Griggs panhard rod and torque arm; front and rear strut/shock tower braces; subframe connectors; welded in 7 point roll bar; Auburn posi-traction rear; 5-lug wheels with Baer 12" front disks (PBR calipers) and Ford rear disks with appropriate SS lines; Tremec 5-speed tranny. I've been to Texas World Speedway twice this year. Let me tell you, it was a humbling experience. I got passed by just about everyone, but had a great time. The car handles better than I can drive it, but upgrades are in order. The brakes got a bit spongy after the third session and that dampened my desire for all out acceleration between turns. There were two other Fox bodied Mustangs at TWS that were among the fastest cars around the course. They both had Griggs suspensions...and very competent drivers. My thoughts are to upgrade the front brakes: Baer 13" vs Cobra 13 "; and install the Griggs tubular K member and severe duty lower control arms. The car is still street driven and will see track use 3-4 times a year. Would it be reasonable to install the suspension upgrades first and then see how that affects braking performance? Thanks, Randy

[Calvin_1976]

Do you have cooling ducts for the brakes? Whatever route you take if you dont have them add them.

[98banana]

Brake ducts would be a good thing. Also, make sure the fluid is fresh and you have a quality fluid in there. You should flush the fluid before every event.

If it were me, I'd concentrate on getting the brakes working better, then get lots of seat time. It sounds like you already have a pretty good setup for a car that sees only 3-4 events a year.

Seat time will make a bigger difference than the suspension upgrades at this point since you said the car handles better than you drive it. And I'm not sure that the suspension upgrades would help the braking problems.

[Randy C]

Yes! That's what I need: common sense answers. Seat time and brakes will come first. I was temporarily overcome with an urge to spend money for shiny hardware. How do you guys feel about the Cobra brakes? I know they can be had for a reasonable price and ducting can be rigged fairly easily. Randy

[98banana]

Originally posted by Randy C
Yes! That's what I need: common sense answers. Seat time and brakes will come first. I was temporarily overcome with an urge to spend money for shiny hardware. How do you guys feel about the Cobra brakes? I know they can be had for a reasonable price and ducting can be rigged fairly easily. Randy

When I had the banana ('98 Cobra 'vert), I had full Griggs, stripped interior, full cage, DOT Hoosiers, the works. And I still had the stock brakes. They worked with very little fade and I pushed it pretty hard all the time. (A little too hard in the end)

A lot of people do upgrade the Cobra brakes to things like Brembo and Stoptech, but I think the Cobra brakes are nice brakes. I'll let some of the more experienced chime in though...

[johnbasf]

I agree with the other post about seat time. The Cobra brakes are very good with ducting. Spend your money on getting the driver better.

[SIUNARA]

You can make your stock brakes function MUCH better then they do now. I did it on my 93 GT. Here's a list of what I did...keep in mind that by doing these things I was able to run pretty quickly at CMP (a track known for abusing brakes) with no brake fade.

1.) New Rotors $90 -- from Advance Auto...lifetime warranty no matter what you do to them. ;)
2.) Russell steel braided brake lines $75
3.) Home made cooling ducts $20 supplies from Lowe's
4.) Cobalt ITR Spec B brake pads $115 Only use on track days...not ideal for use on the street.
5.) Porterfield brake shoes $50
6.) Stainless Steel Caliper Sleeves $30 from MM
7.) Valvoline Synpower brake fluid with boiling points exceeding 500 degrees $6 at K-mart

$386 total...for braking power that helped me pass many Cobra's last March at the Cobra club event. It's more about the driver than ANYTHING else...no matter what anyone tells you. Save your money, as tempting as it will be to spend it...and save yourself the agony and pain of the addiction to buying parts, parts, and more parts. Track time is the key! :D :D

[GUMBALL]

I drive an '86 LX convertible with a '69 351 Windsor, bored 0.030, Mass Air conversion and Trickflow induction and heads. I bought the car new and started modifying it in 1992. Modifications: '87 front struts conversion with red Konis front and rear; K-member from an '88 GT, with welded seams and slotted bolt holes to allow moving it forward about an inch; front lower control arms from a Turbo Bird; Maximum Motorsports caster/camber plates; rear Griggs weight jacker control arms; front coil overs; Griggs panhard rod and torque arm; front and rear strut/shock tower braces; subframe connectors; welded in 7 point roll bar; Auburn posi-traction rear; 5-lug wheels with Baer 12" front disks (PBR calipers) and Ford rear disks with appropriate SS lines; Tremec 5-speed tranny. I've been to Texas World Speedway twice this year. Let me tell you, it was a humbling experience. I got passed by just about everyone, but had a great time. The car handles better than I can drive it, but upgrades are in order. The brakes got a bit spongy after the third session and that dampened my desire for all out acceleration between turns. There were two other Fox bodied Mustangs at TWS that were among the fastest cars around the course. They both had Griggs suspensions...and very competent drivers. My thoughts are to upgrade the front brakes: Baer 13" vs Cobra 13 "; and install the Griggs tubular K member and severe duty lower control arms. The car is still street driven and will see track use 3-4 times a year. Would it be reasonable to install the suspension upgrades first and then see how that affects braking performance? Thanks, Randy
What brake pads are you using - Hawk, and Performance Friction make several different compounds for both street and track applications. Also, when installing cooling ducting - it must feed to the center of the rotor, as the rotor acts like a centrifugal fan. A combination of a pad compound with more "bite" and better brake cooling will do wonders.

[FCorkran]

Yep, brake ducts and better pads for the brakes, seat time for the driver. I've been running '87-spec fronts/SSBC rears on Fox Mustangs for many years (though the Baer A-Sedan kit is on it's way), so you should be good with your current brakes for a good while. If the dust boots aren't melted off of those PBR calipers then you aren't really using them, either due to poor/old fluid, too low a pad temp range or just lack of skill/experience. Doesn't sound like you need bigger rotors yet.

You didn't mention tires you run, if you're on street tires you should probably experience overheating of the front tires due to aggressive braking before the brakes begin to go - if you have good pads. The spongyness you felt might have been caused by the pads getting thin or from using the brakes too hard too soon in a session. Did the rotors look like they had pad material smeared on them after that session?

[GUMBALL]

If you are melting the dust boots, you are also melting the caliper seals....which is a serious problem.

A soft pedal is caused by two things
- air in the system, either from boiling the fluid, or from being drawn past the seals.
- pads worn down too far, causing caliper pistons to be extended too far.

A semi-competition brake pad will have more bite - allowing you to brake more but for a shorter period of time - generating less heat.

[Randy C]

Been a while since my last entry. Just returned from TWS and the SVTOA shindig this past weekend. Rode with and got input from some great drivers. I ditched my 11 year old red Konis and replaced them with the DA units, put a set of Yokohamas on, added home made brake ducts and used Ford heavy duty brake fluid. The car handled well and felt good. Brake fade didn't happen. My face hurt from smiling so much. Can't wait to do it again! Randy :)