caliper rebuild : lip or o-ring seals?

Time for caliper rebuild is coming, and I was wondering was you get upgrading to o-ring type piston compared to just changing the stock lip seals?
Is it worth the price for a non-racing vette?

IMO, YES.....the springs behind the pistons go away, and the O rings are far more stable and less critical to slight rotor run out, making them about the same as any other car.....if severely grooved, maybe to either CORRECTLY resurface the rotors, or just get new ones....NAPA sold me new fronts for only 30 bux each...but that was maybe 5 years ago....supposedly there weren't even China, but USA made.....I don't believe it, but have to admit it LOOKED to be true....

:drink:

denpo said:

Time for caliper rebuild is coming, and I was wondering was you get upgrading to o-ring type piston compared to just changing the stock lip seals?
Is it worth the price for a non-racing vette?

Click to expand...

Yes. Go for the O Rings

Danny

Wilwood D8

denpo said:

Time for caliper rebuild is coming, and I was wondering was you get upgrading to o-ring type piston compared to just changing the stock lip seals?
Is it worth the price for a non-racing vette?

Click to expand...

o-ring pistons did NOT work in my vintage racer...

redvetracr said:

denpo said:

Time for caliper rebuild is coming, and I was wondering was you get upgrading to o-ring type piston compared to just changing the stock lip seals?
Is it worth the price for a non-racing vette?

Click to expand...

o-ring pistons did NOT work in my vintage racer...

Click to expand...

:drink:

Balls out racer, ok, but curious as to what happened?? weight issues or maybe too small a rotor diameter?? or ?

mrvette said:

redvetracr said:

denpo said:

Time for caliper rebuild is coming, and I was wondering was you get upgrading to o-ring type piston compared to just changing the stock lip seals?
Is it worth the price for a non-racing vette?

Click to expand...

o-ring pistons did NOT work in my vintage racer...

Click to expand...

:drink:

Balls out racer, ok, but curious as to what happened?? weight issues or maybe too small a rotor diameter?? or ?

Click to expand...

I can only tell you what happened and what I think the cause was....The pistons I used were billet aluminum o-ring pistons from Zero Tolerance (the guy who originally came up with this idea) these were not the cast o-ring pistons everyone sells today. After grinding the bottom of most of the bores because VB&P doesn`t find the center of the bore before they mill for the sleeves they went together nice, I had a rock hard pedal right up until the car hit the race track then it took two pumps at every corner, I first tried bleeding but that didn`t help, I then noticed aluminum flakes floating in the master so I rebuilt the calipers at the track with my trusty J-56 lip seal pistons, swapped the master cylinder to a new one bled about a litre of SRF through the system and I was back in business. I believe the round o-ring itself doesn`t provide enough of a seal under brake system pressure, maybe these work on the street but not on a road course, at least not on my car.

I'm using the O-ring conversion kit that I got from Mike (Tracdogg2) - a huge improvement over the lip seals that I had before... disclaimer: all four of my calipers were rebuild AutoZone calipers that worked ok and were only 4 years old at the time of the swap... I used DOT5 fluid before and after the swap.... at the time of the O-ring conversion I also switched to semi metallic pads and installed new slotted/drilled rotors...

bottom line: I did too many things at one time to say the O-rings really made a huge difference. I'm happy with my brakes for now and the silly piston springs are gone (don't need those with O-rings) ....

I am only guessing as to what happened to Redvetracr: maybe the O-rings require a tighter tolerance on the bore size? I think the lip seal can "adjust" for a larger bore (we're talking thousands here) as the fluid pressure will force the lip against the bore like an umbrella.... maybe the O-rings fit too loosely in the bore ???

15 years ago, when I got the car, the P/O had put stainless calipers on the car, and of course the rears leaked, so I rebuilt with lip seals, and tossed the springs....ran that way as a DD for ~4 years, started leaking in rear again, here in Florida, put in new lip seals, same thing, couple years, back to leaking....went O ring VBP conversion, lasted some 4 years.....now on a set of replacement O rings....done at two different times....been on road now for maybe 5 years since the left front hose locked up and burnt up everything in site....it was FUGLY under there....

one thing, gotta pay super attention to how you refinish/grind these rotors, IF you do that....you can NOT have any spiral cut pattern left to the finish, it has to be sanded outta there, learned that one the hard way....it's that killed the first O ring install in the rear.....took a while, but I heard a odd clicking, traced to the pads shifting over the surface with each slo speed rotation....wearing the pin and pads....

:crap:

Lip seals or "cup seals" as they are know in the hydraulic world always seal better under wider conditions than oring seals.

On a street machine, I probably would go with the oring seals just to prevent maintenance problems like the run out corrosion etc.

+1 for o-rings.

I replaced all my calipers with rebuilt units from Lone Star. They were SS sleeved but with OEM lip seals. They worked at first but the car still wasn't drivable so sat there while I continued working on the car. One day I noticed that two of the calipers were leaking and had it explained to me that with lack of use, the lip seals can "flatten out" slightly, allowing fluid to seep past.
I removed all the calipers, bought O ring kits from tracdogg and no more leaks.