Installed Tom Hayden's Rear Caliper Upgrade Today

[EA6BPilot]

Installed Tom Hayden\'s Rear Caliper Upgrade Today

I was having trouble with my old rear calipers, so I decided to upgrade with Tom Hayden's 40mm rear calipers. The swapout was easy and suprisingly not too messy (my truck dripped much more brake fluid when I had to change its calipers).

As advised, I installed, bled, drove, and bled again. The difference is nothing short of amazing. I now have a more linear feel in the pedal and can modulate the brake pedal pressure much easier now. I did several 50 to 0 decelerations, increasing brake pedal pressure as I went. At no time today did I lock the front wheels. Granted, if I was doing 100 mph and jammed the pedal as hard as I could, I bet the wheels would lock. But, I am willing to bet they'd lock ALMOST at the same time. The car felt like it squatted more evenly than before.

The biggest convincer of the day for me came about 30 minutes ago. I was traveling home from the base I am stationed at and it started raining. I exited on to a rural road that was soaked and tested the brakes some more. I did another set of 50-0 runs and it was like I stopped on a dime. Had I locked any of the wheels up, I would have slipped and slid as I slowed down (say that 5 times fast!). The car squatted and stayed straight. I bought this kit as a street safety upgrade, and I could not be more impressed. Should I ever get the chance to do a Viper Days, I am sure it will help me out.

I just wanted to say Tom......YOU DA MAN!

Frank

 

[Casey]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Sounds like you are one happy customer!

I am not as happy as you are.....BECAUSE YOU DID NOT POST PICTURES!!

 

[EA6BPilot]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Casey,

SORRY!!! I will get some pics soon. LOL The only real big difference you can see is that I had them powdercoated black to match the fronts. Other than that, they look 100% stock.

I did learn one valuable lesson that can be applied to everyone with stock rear calipers. Before, when I changed the pads, I took off the caliper by working around the parking brake lever. I now know it is pretty easy to slip the cable off and on, thereby exposing the bolt and making it easier to remove and replace. I know that many of you out there who have more mechanical experience will say "duh....that's a no brainer", but for weekend mechanics like me, screwing up something once makes a good learning tool!

 

[Steve-Indy]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

EA6BPilot, THANKS for the update, the report, the cable tip...and, WELCOME back !!!!

Casey...you NEED more brake !!!!! (hope the knee is coming along!!)

 

[Ron]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Thanks Frank. I just got my set of 40's from Tom (also powdercoated black) and look forward to the install soon.

 

[EA6BPilot]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Ron,

The install wasn't bad at all. From what I could tell, the brakes are VERY mushy after the first bleed, so I wouldn't go more than a few miles and keep it under 45 MPH. A quick trip around my neighborhood with some low speed hard braking seemed to be enough. Then, a few miles after the second bleed to get used to the new pedal feel worked well. Good luck!

 

[Chuck 98 RT/10]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Is there a way to pre-load the caliper so you don't have to do the bleed-drive-bleed process?

 

[EA6BPilot]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Chuck,

That is something I don't know. I think Tom said something in a previous thread about that, but I am not sure. I don't think you can, but I may be wrong.

 

[Tom F&L GoR]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Chuck, I've been working on that. The piston has a deep cavity to incorporate the parking brake self-adjusting mechanism. It's why you have to rotate the piston to retract it.

The o-ring at the left seals the brake fluid inside the piston (to the left of the o-ring is a vent exiting in the piston dust boot groove so that the parking brake does not hydraulically lock when you pull the parking brake handle.) The tapered cone actually does the pushing for the parking brake, the ball bearing and washers allow it to rotate around the threaded rod, and there are two snap rings not shown (one to capture the washers and bearing in the piston, another to capture the right side spring and "flange" in the bottom of the piston bore.)

When assembled, the piston is fully retracted, meaning the distance from the o-ring to the cone is longer than shown. The cone probably seals the bottom end of the piston and traps the air around the threaded rod. I've tried filling the cavity before assembly, but I can't assemble it upside down (i.e. I always have the piston heading up when I do it.)

The only thing I can think of is bench-bleeding with the piston pointing down. Even then, the air has to work it's way past the threads inside the cone. Anybody have any ideas?

 

[Ulysses]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Could the solution be as simple as using a pressure bleeder?

 

[Tom F&L GoR]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Ulysses, folks have tried that. The problem (I think) is that the air pocket is not in the "flow" of the fluid being bled. Also, the mating (not exactly sealing) surface of the cone is pretty good at holding the air.

I'll try to find some foreign car shops to ask; sometimes their calipers also include the parking brake.

 

[ACR steve]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Bleed,Drive,Bleed .........(registered trade mark)

 

[Ulysses]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Ulysses, folks have tried that. The problem (I think) is that the air pocket is not in the "flow" of the fluid being bled. Also, the mating (not exactly sealing) surface of the cone is pretty good at holding the air.

I'll try to find some foreign car shops to ask; sometimes their calipers also include the parking brake.

Thanks, good to know.

 

[Chuck 98 RT/10]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

There's got to be a way. DC doesn't do a bleed-drive-bleed when they sell them do they?

 

[Tom F&L GoR]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Out of the mouth of Babels....

Let me pursue it. Otherwise we'll owe Steve royalty payments.

 

[AG98RT10]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

When I had my 40mm rear calipers installed (at Meineke) I sat inside and pumped the brakes, held them, etc., as directed by the crew. They went from left rear to right rear and then the fronts, as I recall, but I don't think they did anything special beyond that. Later that day, I bedded the Brakeman 3's on the new rotors, and took the car to VIR a week or so later... Been driving ever since, including Viperdays and at least 1500 cruising miles. I've not noticed any problems with air in the rear calipers. Do I need to bleed again? This is a mystery to me.
What are the symptoms of trapped air? Does the pedal feel spongy?
I was planning to put new Motul in soon anyway, guess I'll see if things feel any different, but I hadn't noticed any problem.

 

[Eric H]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

I have my set on order from Tom also....thanks Tom!

 

[ViperRay]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Tom,

Charge these guys another $30 and install speedbleeder valves so they'll stop their whining

 

[Jack B]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Tom:

when I installed your kit I pumped out all the fluid, a total bleed. The pedal is rock solid, there doesn't appear to be any trapped air. Those power bleeders you suggested made the job a snap.

I also pulled the o-ring to get more rear bias. After I bedded the new Brakeman 3's, I have been trying to lock up the tires. Since there is more feel or modulation you can now stop right to the point of lock-up without actually locking them.

 

[Irid]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

If you run with sticky tires (i.e. DOT race tires or stickier) and get some heat into them there is a slight rear bias. The rears will lock first, barely. This is with the bias valve in place.

I doubt you could get Pilot Sports sticky enough to see this, but I did on RA1's at the track during testing.

My .02
(the 40mm's rock, highly recommended)

 

[AG98RT10]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Tom:

when I installed your kit I pumped out all the fluid, a total bleed. The pedal is rock solid, there doesn't appear to be any trapped air. Those power bleeders you suggested made the job a snap.

Maybe this is why my install worked - the techs pumped out all the old fluid completely through the system to install the Motul, new SS lines, etc. No problems in a year and 3K miles...

 

[Clown Shoe]

Re: Installed Tom Hayden\'s Rear Caliper Upgrade Today

Had mine about a year now and a few thousand miles and all I can say is thanks Tom. Ghetto