V8Pete Posted July 21, 2018 Share Posted July 21, 2018 2 Quote Link to comment Share on other sites More sharing options...
Snoozin Posted July 23, 2018 Author Share Posted July 23, 2018 Hah holy shit. Quote Link to comment Share on other sites More sharing options...
kws Posted July 24, 2018 Share Posted July 24, 2018 On 7/22/2018 at 03:50, V8Pete said: The same happens with the Vitesse. Almost everything dwarfs it but it's meant to be a "large" car. They just don't make cars like they used to, with all their fancy life saving rubbish now. Quote Link to comment Share on other sites More sharing options...
Snoozin Posted August 26, 2018 Author Share Posted August 26, 2018 Seems to be running pretty well now, hot starts haven't been a problem again (yet) and it goes well. Have given it a couple of good hidings through some twisties, and now that I'm finally getting to learn about the car it's becoming more and more fun to hoon. So I went to Caffeine & Classics this morning, then decided I'd pull it apart. Again. This time around, a brake refresh. So first things first, acquire parts. Sterling Brake and Clutch sorted me with a set of fresh Zimmerman rotors, these are 298mm front and 300mm rear. Always a great price and the best service ever from Blair there, support the hell out of them. Great at finding stuff that no one else seems to be able to find. 1991 Porsche 944 S2-488 by Richard Opie, on Flickr 1991 Porsche 944 S2-492 by Richard Opie, on Flickr I also bought a full set of caliper seals and dust boots, as I had some concerns the front calipers were sticking and causing uneven pad wear. Anyway more on that later. So I chucked al my gear in the boot, gathered up my tools and set off to George's place to chuck the car on his hoist and crack into it. 1991 Porsche 944 S2-498 by Richard Opie, on Flickr First up, here's a look at the calipers. Rears, grubby. Sort of underslung Brembo 4-pots. Handbrake is one of those internal drum kind. 1991 Porsche 944 S2-500 by Richard Opie, on Flickr 1991 Porsche 944 S2-510 by Richard Opie, on Flickr Fronts, a Brembo 4-pot again. In this case I've got a bit of a problem with the clear coat going cloudy on both front calipers. 1991 Porsche 944 S2-513 by Richard Opie, on Flickr 1991 Porsche 944 S2-521 by Richard Opie, on Flickr Fairly straightforward to remove really. Release the spring clip on the top, remove the wear sensor and pull pads out after pushing the pistons back. I was a bit agricultural and used a pair of polygrips to squeeze them back, as the plan is to refinish the calipers anyway. Front hubs look pretty boring, just an aluminium casting with a toothed ring on them for the ABS sensor. Rears are a bit more interesting, with the whole handbrake thing going on. 1991 Porsche 944 S2-526 by Richard Opie, on Flickr Some positives here. Studs are 55mm long (end to end) and I want to install some that are 10mm longer to accommodate some spacers before I eventually throw the 17" wheels on. Plenty of space behind the hub to install these without pulling the axles and making a massive job of it. Yay! Anyway, the calipers. Once I got them off, I thought I'd have a crack at squeezing the pistons in. They all moved fluidly in, and all the dust seals are in great condition. So I'm likely going to leave them be and not throw new seals at them... instead I'll clean and mask off that internal area before painting and it should all go to plan. A friend just drew up new decals for me too. 1991 Porsche 944 S2-546 by Richard Opie, on Flickr They might all look the same.... but here's the crucial difference between front and rear. Front - staggered pistons, with a 40mm and 36mm piston combo. 1991 Porsche 944 S2-559 by Richard Opie, on Flickr Rear, staggered again but a 30mm and 28mm arrangement. 1991 Porsche 944 S2-555 by Richard Opie, on Flickr Any tips on what to do when it comes to bleeding will be appreciated, I have never pissed around with a 4-piston caliper before with a bleed nipple on either side of the caliper. I'm guessing you just do it one at a time, but inside or outside first? 2 1 Quote Link to comment Share on other sites More sharing options...
KKtrips Posted August 26, 2018 Share Posted August 26, 2018 Always start with the furtherest away from the master cylinder. Callipers with dual bleed nipples, whatever is further away from the brake hose inlet. 1 Quote Link to comment Share on other sites More sharing options...
Snoozin Posted August 26, 2018 Author Share Posted August 26, 2018 Mint, cheers for that. So start with outside then go to inside. Sounds like it's tedious! Quote Link to comment Share on other sites More sharing options...
Mof Posted August 26, 2018 Share Posted August 26, 2018 School me please, does the bigger piston trail the smaller/the disc gets to the smaller one first? Or the other way around? Quote Link to comment Share on other sites More sharing options...
KKtrips Posted August 26, 2018 Share Posted August 26, 2018 7 hours ago, Snoozin said: Mint, cheers for that. So start with outside then go to inside. Sounds like it's tedious! No, do one calliper/corner at a time. Quote Link to comment Share on other sites More sharing options...
AllTorque Posted August 26, 2018 Share Posted August 26, 2018 Wilwood calipers have bore sizes that increase in size from front to rear. This allows a pressure differential between the leading and trailing edge of the caliper, thus providing a more even wear pattern along the entire length of the brake pad, hence it controls pad taper. This is necessary because incandescent material and debris from the leading edge of the pad is trapped between the pad and rotor; it tends to float the trailing edge of the pad off the rotor. A larger piston at the trailing edge of the pad provides more pressure to compensate for this debris buildup and keep the pad flat against the rotor. 3 2 Quote Link to comment Share on other sites More sharing options...
AllTorque Posted August 26, 2018 Share Posted August 26, 2018 5 1 Quote Link to comment Share on other sites More sharing options...
Snoozin Posted August 26, 2018 Author Share Posted August 26, 2018 31 minutes ago, KKtrips said: No, do one calliper/corner at a time. Yeah I mean the inside/outside bleeders. Quote Link to comment Share on other sites More sharing options...
kws Posted August 26, 2018 Share Posted August 26, 2018 10 hours ago, KKtrips said: Always start with the furtherest away from the master cylinder. Callipers with dual bleed nipples, whatever is further away from the brake hose inlet. Its not crazy like the AP calipers on a Vitesse, where both bleed nipples on each caliper need to be bled at the same time? Quote Link to comment Share on other sites More sharing options...
KKtrips Posted August 26, 2018 Share Posted August 26, 2018 2 hours ago, Snoozin said: Yeah I mean the inside/outside bleeders. Yup. Outside of calliper furtherest away from master cylinder first. Then inside of that one, then move to the next furtherest outside... etc. 2 Quote Link to comment Share on other sites More sharing options...
Snoozin Posted August 26, 2018 Author Share Posted August 26, 2018 36 minutes ago, kws said: Its not crazy like the AP calipers on a Vitesse, where both bleed nipples on each caliper need to be bled at the same time? How does that even work, would the fluid just not take the shortest path to the nearest bleeder every time? Quote Link to comment Share on other sites More sharing options...
sheepers Posted August 26, 2018 Share Posted August 26, 2018 your trying to apply logical thinking to something british. it doesn't make and sense. or work. 5 1 Quote Link to comment Share on other sites More sharing options...
kws Posted August 27, 2018 Share Posted August 27, 2018 6 hours ago, sheepers said: your trying to apply logical thinking to something british. it doesn't make and sense. or work. It did work, somehow. You bleed the two together, and then you bleed the third one afterwards. Three nipples, and not even the good kind. 1 1 Quote Link to comment Share on other sites More sharing options...
V8Pete Posted August 28, 2018 Share Posted August 28, 2018 1 Quote Link to comment Share on other sites More sharing options...
Snoozin Posted August 28, 2018 Author Share Posted August 28, 2018 It'll still cost another $86k in repairs and maintenance. 4 Quote Link to comment Share on other sites More sharing options...
xsspeed Posted August 29, 2018 Share Posted August 29, 2018 is there something special about that red 944? Quote Link to comment Share on other sites More sharing options...
Snoozin Posted August 29, 2018 Author Share Posted August 29, 2018 Not overly. It's an '89 Turbo with low km. The final year of the turbo, all were turbo S spec. The watercooled stuff is beginning to follow it's aircooled cuzzy bros now though, partly why I got back into the market when I could. 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.