113 replies to this topic

[JohnTurbo]

Okies...

 

Drilled, counterbores.

 

 

Drilled out to 10.5 for the helicoil kit. Then tapping the hole to depth with the special tap.

Then you just screw the coil in with one tool, and snap the tang off with another. Works really well!

 

 

 

Fitted:-

 

 

Pads, new pins, banjos bolted up, bled.

I know Yellowstuffs arent good in the 2 pots, but were great in the Hispecs so I've bought a full set. I suspect its to do with pad area.

The question really is how are they in the MGTF? haha.

 

 

Finally...wheels fitted.

 

Edited by JohnTurbo, 09 May 2013 - 09:56 PM.

[CocoPops]

Nice!

[techieboy]

If they haven't fallen off/cracked/exploded/buckled/melted in the next 7 days, I'll send you mine.

[JohnTurbo]

:-)

 

Lol.

 

Very er...kind...Techie.

[techieboy]

I even found them in the garage yesterday. Had no problem knocking out the pad retaining pins. Which was probably down to the 3mm thick layer of grease/oil coating over the entire calipers (including most of the pads). God knows what the car they came off was like but the bit I did clean off with a rag looks absolutely mint underneath. Maybe he took the oily rag approach to anti-corrosion a little too far.

[JohnTurbo]

Next step is to trial remove the middle cross bolts ;-) Pedal feel btw is sublime!

[techieboy]

Next step is to trial remove the middle cross bolts ;-)

Sod that. No way am I trying, let alone going anywhere near it with my cordless drill.

Pedal feel btw is sublime!

Shushhh.

[mbes2]

Top work John..... Now that will really confuse people.... Is it a MG........A Vauxhall..... But I think its maybe a Lotus....

 

Whens the group "John will fix it" buy start ? 

 

 

Keep updated once your on track with them

 

[starlight]

Great work there John. Just need to find a local friendly machinist. Do you have an overview of the machining requirements for the calipers?

[JohnTurbo]

Had a play with them today, they stop well. My rear pads are currently pants though so need that sorting.

(My rear yellows are due to arrive on Monday)

I also miss the over servo'd feel of the hispec/ftr setup - it really stopped very well, but this should be better for last second braking on the track.

+ If i'd bought RC6 pads I'd get the over sevo'd feel back!

 

I de-MG'd them, and hit them with Red hammerite which is in your face, but looks good with the wheels on.

 

 

 

Starlight,

 

After removing the pads, pins and middle cross bolts:-

 

1) Bandsaw off the bracket roughly.

2) Face the caliper off until the 'bracket' just cleans off - a web just disappears before its time to stop. If i remember I'll get a measurement top to bottom.

3) Pick up the centre of the caliper...bore 2x 10mm holes 150mm apart, even about the radial centre line and 27.5mm offset from the centre axially.

4) Add very shallow counter bores to the tops of the caliper for the heads of the capheads. - Buy 85mm M10 capheads for attachment to hub,

5) Pad seats need to be ground clear a little with an angle griner/dremel.

6) Drill the crossbolt holes through to 10mm, add counterbores in the miller.

7) Drill to 10.5mm just upto the radial mounting holes, tap for helicoils and add helicoils from the outside. Reuse original crossbolts.

 

Thats the lot. Banjo type hoses needed - available from EP.

[JohnTurbo]

Hmm....also you may recal me saying the pistons are not placed symmetrically. -This is to give even pad wear; the main failing of the stock 2 pots IMHO.

 

Well...

 

 

The calipers are in fron tof the axle, which means i'm going to have to swap my calipers left/right and swap the bleed nipples/crossover pipes top/bottom.

Wish I'd noticed earlier!

[JohnTurbo]

Lee - yours are also wrong buddy (in the photo at least)

[starlight]

Thank John! Really appreciate the work you have done there to make it easier for the rest of us!

[ArticMonkey]

However my AP 4pots are fitted correct and are the same way you currently have them. You want the bleed nipple at the top so you can bleed easier with air pockets traveling upwards.

[JohnTurbo]

Arctic... its not about the nipples, they can be swapped with the pipes as per my post above. Yes the nipples need to be at the top. For you the small piston should see the disc first. For me the piston that is set back should see the disc first. Two different methods of reduced pressure on the pads leading edge.

[ArticMonkey]

That makes sense. When I removed my two pots you could see how bad the wear was on half the pad. Are you sticking with the same calliper on the rear or transferring the fronts to the rear?

[techieboy]

John, as our resident brake sizing/calculation wizard, do you know what pressure our brake system runs at (at least what the max pressure is in full-on heavy boot stomping on the middle pedal mode)?

[JohnTurbo]

If there was no booster, and the mech advantage of the pedal was 4:1, 40kg load on the pedal woild give around 500psi/35bar. Always the max pressure will be affected by the force you can exert. 2000psi is probably fine to view as a safe maximum. Why do you ask?

[techieboy]

My new data logger turned up a couple of days ago and I'm just digging through my box of collected pikey (i.e. fcuked if I'm paying "motorsport" prices) sensors and wondered about how viable it was to tee a brake pressure sensor into the system somewhere, as it appears I have one from a previous Audi. Bosch specs for it say it's good for up to 250bar but had no idea if that was okay. Just need to find the correct Tyco/AMP wiring connector for it now and work out where it can go. Ideally I'd tee into one of the two lines coming out of the master cylinder but as that's upstream of the ABS actuator, not sure whether that's a good idea or will even be accurate.

[Mike (Cliffie)]

1 - the new mounting holes are where AP would put them. I used the AP caliper drawing for the exact position. 2 - the brakes are similar to standard, just they don't get hot like the two pots. 3 - rears are the standard calipers/discs with mintex 1144 pads, the fronts have mintex 1144 pads too. I haven't noticed any issues with the brakes. 4 - I fitted them last year, probably done 1 mile or so.

EFA