Need a little advice, what are you all using?

i have a set of AP 4 pots fitted to my sti 5 running big bhp and i intend to do as many track days as possible next year and for the time being still to be used as a road car. so i need them to hold up on the track and not fade but also not take hard driving to get them to heat up for road use

i have a set of 17" oz super t (the original style) so what would be

a) the biggest disk i could get away with?

b) the best make of disk?

cheers

steve

 

Hi Steve,

What model calipers are they and what is your current disc size?

Best discs would be PF, if available for your fitment followed by AP discs.

Both are curved vane race discs. Avoid cheap replacement discs.

 

np idea what model they are bob they were fitted to the car when i bought it, you may know as it used to be bob rawles car (sti 5) i can get a pic of the caliper if you need as i would not of thought the model number would be visable to the eye, sqme as disk size until i get the wheel off i have no idea what they are.

 

only one i have at the minute and noo idea if you could tell from a pic

 

they have an AP sticker in the lower bottom corner not the normal big AP logo on the caliper if you know what i mean

 

Hi Steve
Your calipers are the common CP5200 series calipers , and if they are 17" wheels the discs look like the smaller 304mm not 330mm , perhaps you should measure them to check.

You cannot fit larger AP discs without changing the bells as well , but I can supply you our own make 330mm discs to fit the 304mm bells , I can also supply you our own make 304mm discs , both types will be grooved , these are £295 a pair and come with a 12 month guarantee against warping even if you do track days , have fitted loads of these to rally cars as well as plenty of road cars , so they are well proven.

I can also supply you AP discs , can get you a current price tomorrow , AP or PF discs will be about £500 a pair.

Pad wise , I doubt you would get something that works from cold perfectly as well as being fade free on the track , a good all round pad is the Ferodo DS2500 , these are around £90 a set for your calipers , again I can get you an exact price when I'm back in work tomorrow
Cheers Ian
01656 723060

 

thanks for your input ian, yes they are 17" wheels.

sorry this is going to sound very dumb but here it goes - BELLS - is that another name for caliper?

the pads are only a month or so old and are the ds2500 from what the previous owner said but he did say the disks will need replacing early in the year so thought i would get thm ut the way before i forget.

 

The bells are the alloy pieces that are bolted into the centre of the disc , if the pads are new , they can be used on new discs , you would need to flat them off with sand paper / emery cloth to make sure they were perfectly flat again as they would have worn to the shape of the current discs
Cheers Ian

 

thanks ian

for example if i only have the 304mm disks and wanted to fit larger 330mm how mauch ar the bells? and is it an easy job to change them?

is it worth going from the 304 - 330 would i notice much difference in stopping power?

just thinking is it worth it all, or might just take advantage of the gb on a set of k sports 8 pots as that must be twice the stopping power compared to my 4 pots

 

HI
No the 8 pots wont give you twice the stopping power , dont be fooled into thinking more pots = better braking , they would be slightly better as they have a larger pad , but the difference wouldn't be that much , with an 8 pot caliper , the pistons are much smaller , otherwise the master cylinder wouldn't be able to cope with the fluid displacement , the smaller diameter pistons will spread the pressure on a smaller area of the pad compared to the set up you have now , with larger pistons the pressure is spread nearly the full width of the pads , my opinion , use your AP's.

You dont have to change the bells , if you did , our ones are £150 a pair , AP bells would be probably double that , as I have mentioned though , I can supply you 330mm discs to fit your 304mm bells , this will give you a good increase in braking power going to 330's.

Cheers Ian

 

OK great thanks for all that ian, as for the bells one you say a pair would that do both sides or do i need to pairs?

 

you have one bell per disc , so a pair of bells for a pair of discs
Cheers Ian

 

I used Ian's grooved discs for a 2 day track day, as well as a local hill climb.

On the smaller circuit at Le Mans, everyone was melting brakes, me included, but for the first time ever for me, my discs didnt warp at all, so very impressed.

I use EBC yellow stuff, which arent a bad compromise, but would say that the pad quality doesnt seem consistent- half of people had loads of pad left, and the other half went right through the pads in a day! Thats more than simply a driving style difference.