R/R rear subframe and/or trailing arms trick

#1

Just figured out a trick that saved a bunch of time removing the rear end.

One of the pains in the ass at R/R the rear subframe or trailing arms is the park brakes. I like my park brakes so I’ve kept them. But the last time I R/R’d the rear subframe I had to disassemble the rear brakes in order to disconnect the park brake cable and that was a pita.

But this time I figured out a better way to do it.

At the ebrake pull handle undo the 10mm nuts that anchor the cable. Then get under the rear of the car and pull hard on the rubber ebrake cable housings about where they disappear into the underside of the car. They should come out a couple feet, but they won’t quite come out all the way.

The ebrake cable goes into a “pipe” sort of thing that pieces the underside of the car. The last inch of that pipe is where the cable hangs up when you try to pull it out. Get a set of pliers or something and rotate the piece that forms that last inch of pipe. One you have it rotating a bit, start tugging until it comes free. Now the ebrake cable will pull right out of the car.

And now you don’t have to R/R the entire ebrake mechanism that is in the rear hubs.

#2

That is an acceptable way of removing the rear subframe assembly, if that subframe, etc is going to be re-installed. However, if you will be using a different subframe assembly, changing trailing arms, or replacing rear wheel bearings there is no labor savings over the more conventional method of disassembling the parking brakes.

There are those that assert that a race car shouldn’t have a parking brake. I’m from a different school and retain mine.

#3

I don’t like to sacrifice performance for convenience. I would like a lockable hydraulic handbrake but it wouldn’t be legal.

#4

The reason you’re not getting on the podium is your parking brakes?

#5

i don’t see any advantageous reason to remove the parking brake system, only reason to leave it in. we recently put a rear subframe in from another car which didn’t have a parking brake and it has been nothing but a head ache not having the parking break, we have to carry a wheel chalk everywhere we go. a lot of the time we like to turn the cars on and let them warm up which means we can’t leave it in gear if its on a hill.

As for removing the subframe i have used that method every time, and it has worked great for me!

#6

The reason you’re not getting on the podium is your parking brakes?[/quote]

So far the reason I’m not on the podium is because I’m not doing comp school until April. I know say what you will but it’s still unsprung weight.

#7

The reason you’re not getting on the podium is your parking brakes?[/quote]

So far the reason I’m not on the podium is because I’m not doing comp school until April. I know say what you will but it’s still unsprung weight.[/quote]
Re. not getting on the podium. Yes. Sometimes much of the fun of a joke is making it subtle enough that it’s hard to know if it was meant as a joke.

Re. unsprung weight. I hear you, but a person could remove one of the ebrakes and half the weight, yet I don’t see anyone bothering. I think that you’ll find that little tweaks like that are 90% mildly interesting late night projects, 10% imagined performance enhancement, and 0% genuine utility.

I’d remove one of the ebrakes, except that if the day comes that I have a total brake failure and I hit the ebrake to slow me down a little, I want symmetric braking back there.

#8

I kinda doubt the “emergency” brakes would do much good in a real emergency, but they are great when loading the trailer. For that reason alone I think they’re worth keeping.

I’m not worried that anyone is going to beat me because I’m at a performance disadvantage due to the e-brake weight.

To get slightly back on topic… Thanks for the suggestion. I’ll try that the next time I have to pull the trailing arms.

#9

As “brakes of last resort” the parking brakes probably won’t let you make the corner at the end of the straight when you discover that you have no brakes. But they just might keep you from impacting a wall at full speed. That is sufficient reason, in my opinion, to retain them.

#10

5-6yrs ago a Viper lost it’s brakes on the CMP front stretch. Or maybe the driver was trying left foot braking, there’s different versions of the cause of that story. As they headed thru turn 1, clearly in trouble, either driver or instructor pulled the ebrake, IIRC.

Even if the ebrake sheds only 10mph in a pinch, that can be a big deal. Ek=1/2mV^2. When your V is squared, 10mph can be a big deal.

Google CMP Viper crash and you’ll find the video.