Porsche 997 rear calipers advise

[Ash-S3]

Howsit guys

Need some advise i read through the brake thread but saw no info on 997 4 pot brembo rear calipers .
I recently bought a set but now im worried they actually might not work on my 2002 audi S3 8l as the pistons might be to small (they look around 34mm)

a picture of them

 

[jojo]

They will look good, and they will work, just not as effective as a front calliper setup.

 

[daz-20vt]

measure the pistons exact.
but not a conversion I've seen before. how much did you pay as I'd be tempted to sell and start again

 

[Ash-S3]

They will look good, and they will work, just not as effective as a front calliper setup.

car wont ever see a track so its basically for just normal road use as this is my daily drive i love the look of them and would be sad if i had to sell them

measure the pistons exact.
but not a conversion I've seen before. how much did you pay as I'd be tempted to sell and start again

google says they infact 34mm pistons

 

[jojo]

measure the pistons exact.
but not a conversion I've seen before. how much did you pay as I'd be tempted to sell and start again

Probably got a good deal on them? It's the front calipers that fetch top money. I personally see the fitting of the rear calipers for a front brake setup as a bodge job.

2 of the most important things that's needed to stop you from hitting the thing in front are your brakes and tyres. 2 things I won't skimp on ever again, if the car is anything quicker than fast. But that's just me.

 

[Ash-S3]

Probably got a good deal on them? It's the front calipers that fetch top money. I personally see the fitting of the rear calipers for a front brake setup as a bodge job.

2 of the most important things that's needed to stop you from hitting the thing in front are your brakes and tyres. 2 things I won't skimp on ever again, if the car is anything quicker than fast. But that's just me.

Got them for a decent price but still alot of cash haha.. its rather easy to install them also
got two engineers at work working out the clamping force etc for me now

 

[daz-20vt]

problem is fella though they may be 4 pot the rear set ups normally have lower clamping force then oem calipers due to piston sizes.
there is a good chance these will result in a downgrade.
very common knowledge on here.
also prison's are usually different sizes are all 4 definitely 34mm

 

[Ash-S3]

problem is fella though they may be 4 pot the rear set ups normally have lower clamping force then oem calipers due to piston sizes.
there is a good chance these will result in a downgrade.
very common knowledge on here.
also prison's are usually different sizes are all 4 definitely 34mm

this is exactly what im worried about bud..will need to check if all 4 are the same..

 

[daz-20vt]

just remember these things are the most important part of the car.
it would be a shame to sell up I'm sure but you have to be safe!!! keep us posted on them!

 

[kwistof]

What are the part numbers of the brakes?

Saying they are off a 997 is not much help as there are several different 911 997 models with different variations of rear brakes.

 

[Prawn]

Stock 54mm sliding caliper has an area of 2290mm^2

Lcr brembo has an area or 2274mm^2

A rear caliper with 4x 34mm pistons has an area of 1816mm^2

That's 26% LESS braking force than the stock calipers for a given master cylinder size and pedal pressure.

Back on eBay they go! Sorry.

 

[Stuson]

I have to admit that when I was looking for Brembo four pots for my A3 that I was more or less conned into believing from the seller, that this was a brake upgrade.
Got reconditioned rear Cayenne callipers with pads and VAG fitting kit for 312mm discs at what I though was a good price. Even with braided hoses they were absolute f#*king sh ite. Far less stopping power than my standard callipers, even with below average pads. In the end I finally sold them for 1/3 of what I paid for them, not good.
I am now running LCR Brembo's and they are awesome compared to the standard set up. Got a reconditioned set with pads and discs from a cupra.net member for £600.

 

[Ash-S3]

Hi guys thank you very much for the useful information much appreciate wow.. I've moved them on at least but now I managed to source a set of Alfa GTV 4 pot Brembo front calipers... I haven't bought them as yet as I'll rather get some advice again.. The specs are as follows.. Allow up to a 32mm thick disc and piston diameters are 38mm and 42mm.. This is far greater then the Porsche ones but would it be worthwhile.. Pads are also easy to get and not to expensive.thanks again

 

[Prawn]

38 and 42 will be OK.

Slightly on the large side, but not enough to give you too many worries. Hydraulically you'll have slightly more power than stock, at the expense of a slightly longer pedal travel. Much of that additional pedal travel will be offset by the stiffer caliper though.

For reference, pistons in my AP setup are 38.1 and 41.3mm and they're fantastic.

 

[<tuffty/>]

Are they radial or lug mount? what diameter disc do they support? bare in mind std S3 312mm discs are 25mm thick and 323mmm LCR are 28mm thick...

<tuffty/>

 

[Ash-S3]

Thanks prawn
I'm just waiting for the guy to send me actual pictures..
Here is a picture I grabbed off the Internet of what they look like.. ( these look terrible though haha)

Can't find anything on disc sized as yet..

 

[<tuffty/>]

I assume they were previously fitted to a VAG car with those adaptors?

<tuffty/>

 

[Ash-S3]

I assume they were previously fitted to a VAG car with those adaptors?

<tuffty/>

Not to sure bud.. The ones i might get are off an actual Alfa GTV.. The picture shown is just a random one off the net.. I'll have to check it out and see if an adaptor will work bolting position etc

 

[<tuffty/>]

You will need an adaptor to get these to fit...

Personally I would hold out for a set of LCR...

<tuffty/>

 

[Ash-S3]

You will need an adaptor to get these to fit...

Personally I would hold out for a set of LCR...

<tuffty/>

Yes I can design one no problem that's pretty much the least of my worry.

I would love to get LCR calipers but that car never came to South Africa.. We only got the Ibiza Cupra which came out with 4 pot AP racing calipers.. And seat pulled out the country so they super rare and if you buy it new it's crazy expensive. Even AP racing in SA is expensive.. Only down fall but let's see I'll keep looking