Brembo brake upgrade

[960kg]

http://www.cheapsportscar.net/hydraulics.php
I hope this helps.. I believe in most cases the effectiveness of the calipers will out way the extra travel.
Also a four pot caliper may actually travel less as the single Volvo piston is doing the work of two by the equal oppostie forces applied to create the clamping force on each side.

With a small amount of maths you could work it out.We just need the piston sizes of both units and distance of travel required.

I have just had a read of this link and ok, so it is interesting but at the end of the day it doesn`t matter how much fluid is supposedly moved as it "doesn`t move does it"!!......if it moved then you would have a leak!

There is give in the pedal but when the system is bled properly so no air then the pedal is hard, the pads are damn nigh against the discs as when jacked up and you turn a wheel you can hear them touch, also after a couple of days of non use when first moving the car you can here the newly formed rust rubbing so all this about volume movement is not what it seems? Yes, there maybe more volume in the system due to larger calipers but the movement when the brakes are applied is minimal as you cannot compress hydraulic fluid.

Also as said in the link two larger piston`s in a caliper will give more pressure than a four pot caliper. You will only get better or more pressure if you do as said in the link and have a larger inside diameter master cylinder.

Same principal as gearing!

[Wobbly Dave]

Certainly a case for testing them at an MOT station once fitted

[Harvey]

Just a though is the R brake master cylinder the same part number as the rest of the range if it's different then you might problem.

[oblark]

If the master cylinder is a problem with a 4 pot brake upgrade then why does IPD do a kit so that Porsche brakes can be fitted to a 850 ?

http://www.ipdusa.com/products/8250/...ake-kit-850-70

[Harvey]

If the master cylinder is a problem with a 4 pot brake upgrade then why does IPD do a kit so that Porsche brakes can be fitted to a 850 ?

http://www.ipdusa.com/products/8250/...ake-kit-850-70

As you say they don't say there is any need for any outher work,just thinking the new calipers don't float in the hub so there is less play movment ,what is the dia of the 4 pistons / what is the dia of the old piston.

[JUDGENINJA]

I like this sort of thread... None of us actually know the definitive answer.

[960kg]

If the master cylinder is a problem with a 4 pot brake upgrade then why does IPD do a kit so that Porsche brakes can be fitted to a 850 ?

http://www.ipdusa.com/products/8250/...ake-kit-850-70

There probably isn`t a problem with the master cylinder.......don`t forget there are oilways inside the calipers so what size or diameter are they? If you squirt hydraulic fluid through a smaller oilway you may or may not get a higher pressure or it may be the other way around, the oilways may be bigger , who knows?

You pay for development that`s why they are expensive.....but then again you know they will work.

[Harvey]

If you squirt hydraulic fluid through a smaller oilway you may or may not get a higher pressure or it may be the other way around, the oilways may be bigger

If the oil ways are smaller the flow will be lower but the pressure will be the same,but the amount oil fluid that's moves around is very low.

[JUDGENINJA]

I wonder how Much development actually went it the upgrade kits.. Probably not as much as you think.

The calipers will be a generic size used for multiple cars. It is only the carriers that are the developed part.
If there is any work carried out on the calipers I could bet that it was an one paper calculation or CAD.
Do AP supply a validation document to support type approval?

[V70 Graham]

I like this sort of thread... None of us actually know the definitive answer.

Bottom line is, when Rob presses the pedal, he'll either stop quickly.....or bum clenchingly s l o w l y

[JUDGENINJA]

.... Or possibly bum clench very quickly also!!'

[Wobbly Dave]

As you say they don't say there is any need for any outher work,just thinking the new calipers don't float in the hub so there is less play movment ,what is the dia of the 4 pistons / what is the dia of the old piston.

There isn't going to be an issue if the total volume moved is the same as before. The only risk exists if the volume is different, because you still need to ensure that the piston travel remains viable even when the pads are down to their wear limit.

[Yosser]

There isn't going to be an issue if the total volume moved is the same as before. The only risk exists if the volume is different, because you still need to ensure that the piston travel remains viable even when the pads are down to their wear limit.

Pad wear has nothing to do with anything - the pistons don't retract fully and they shouldn't have to travel any further from rest to applied irrespective of pad wear. Over time, fluid from the master cylinder will have filled the cylinder in which the piston moves and - as the fluid is as good as incompressible - the small movement of the master cylinder will have the same effect at the pad.

I understand that the brakes are very very important, and screwing around with them should be done with caution, but if you're not comfortable with these modifications then don't do them.

Personally, I trust that the manufacturer of my BBK (AP Racing) are sufficiently good at what they do that they wouldn't cobble together some old crap that wouldn't work or would be dangerous. I also trust the real world experiences of others who have done hundreds (thousands?) of track miles on the same setup - the same goes for those who have done extensive mileage on the Porsche conversion.

[Wobbly Dave]

Sorry my bad - indeed you're correct about the travel & pad wear issue.

How do you get on for longevity & maintenance costs of the AP kit? How much are your replacement pads & rotors?

[Yosser]

How do you get on for longevity & maintenance costs of the AP kit? How much are your replacement pads & rotors?

There is the rub...

Rotors are the expensive part. The original kit was 325mm but I have adapted this to 330mm as the rotors are more available/less expensive. I recently fitted a pair of performance friction rotors which I paid around £200 for (the pair). I think they are a good bit more than this ordinarily. Godspeed do lower cost replacements but I've read varying feedback about them.

I haven't done enough running to comment on longevity, but the wear spec recommended by AP is very tight. The rotors new are 28mm and I think they advise replacement at 26mm. For this reason I would favour a pad that is kinder to the disc.

Pads are no more expensive than good pads for the standard setup. I currently have EBC yellowstuff pads and (from memory) they were £60ish. DS2500's are around twice that I think. Carbotech are £200ish IIRC.

So far (a few hundred road miles and one track day) the brakes are excellent, I probably haven't explored their full potential yet.

[Wobbly Dave]

This is what always put me off. I probably do more track days than most members - maybe 3 - 4 per year. I run DS2500 on standard 302mm disks. Each track day will stand me at least 3 - 400 in maintenance in order to ensure the life of the engine.

I just don't think I could warrant the outlay plus the extra maintenance - so perhaps the Porsche setup is the best compromise? Still AP is a very nice piece of kit.

Maybe I will treat myself once the engine upgrade is done, assuming that 'er indoors never finds out the true cost LOL.

I hope that Rob may have stumbled on a porsche alternative. I await the outcome with baited breath.

[Lsvolvo1]

Porsche caliper can be a bit fat in the fitting, Renault caliper much slimmer

[oblark]

Fitted the Clio brembo calipers and the 320mm discs today.





To all the sceptics and the captain negatives once the brakes where bleed the brake pedal was rock solid, even the fact the brake pads need to be bedded in the brakes are better than standard.

[martybelfastt5]

now the qeestion is are the calliper brackets avail or measurements ect? look great by the way

[Harvey]

Nice job,great to see them on your motor ,is the pedal any higher/lower than before when stopping quickly ?.
So what sort of gap do you have caliper to rim outer edge and what sort of gap to the wheel spokes ,did it work out as you expected as you said before?.
What did the machine shop make the holders out off?.