Stoptech BBK / turn-in

[dan101smith]

Having just got back from thraping the M3 round Snetterton yesterday, two things stood out as weaknesses for me (well three if we include the driver):

1. The brakes. I've got new OEM discs all round, plus Pagid RS29s, braided lines, 5.1 fluid, but they just didn't seem comfortable hauling the car down from big speeds at the end of Revett straight. So, I'm considering a BBK. Looking on the CA Automotive site, they list a Stoptech 4 pot front kit with 332x32 slotted discs for £1656.99 - has anyone tried this, and are they any good? What pads can you use with these - I'm assuming my Pagids won't fit?

2. The turn-in. Just didn't feel sharp enough, like there's a load of slack to be taken up in the steering before the car responds. Now, I'd adjusted both ARBs to soft as I was expecting rain yesterday (that luckily never came) so I'd imagine setting front back to hard will improve turn-in if compromise overall front end grip, but anything else I can look at? Looking at the pics from the day, the car barely rolls (on coilovers), is on standard, new PS2s so what else can I look at?

Oh, and problem 3. Needs about another 100bhp really....

[m12_nathan]

1. get the AP kit
2. What camber \ caster are you running?

[dan101smith]

I'm indifferent to brand, as long as the performance is right - if the APs are £150 better than Stoptech, then fine by me.

I've got a printout at home of all the geometry settings, I'll dig it out later.

I think part of the problem is caused by the steering rack itself - it seems terrible around the straightahead. I'm going to see if I can source a Z3 rack, and see what difference it makes.

[m12_nathan]

AP 4 pot kit is about the same price, the 6 pot kit is more though.

http://www.thorneymotorsport.co.uk/products/produc...

Though I would go for the part number with g8 at the end for grooved rather than drilled disks, price is the same for either part number at the place below so you should be able to get the grooved 4 pot kit for £1650 inc as above.

http://www.evo-s.co.uk/shop/product_info.php?cPath...

[dan101smith]

Thanks.

Never having driven a car with an AP setup before, will I notice much difference over what I currently have? I presume I can use the same pads in the AP calipers?

[Cheburator mk2]

m12_nathan said:

1. get the AP kit
2. What camber \ caster are you running?

Why should he go for the AP 4-pot kit over the Brembo Big Reds which come with the StopTech Kit? Surely if good enough for the 993 GT2, they should be good enough for the M3? 322mm x 32 disks are £240 incl VAT and delivery for Genuine Porsche items if you know where to ask. There are billions of pad options - Hawk, Cool Carbon, Pagid, Ferodo, Performance Friction etc? Or am I missing something?

P.S 6-pot APs are good, but then so are 6-pot Brembos off the 996GT3 Mk2 996TT (and much cheaper)...

[houlbt]

oh not the old Brembo vs AP argument.... yawn.

I love my AP's the most. Worth checking these guys out for a price...

http://www.bmsport.com/e-shop4(2008).asp

[m12_nathan]

Cheburator mk2 said:

m12_nathan said:

1. get the AP kit
2. What camber \ caster are you running?

Why should he go for the AP 4-pot kit over the Brembo Big Reds which come with the StopTech Kit? Surely if good enough for the 993 GT2, they should be good enough for the M3? 322mm x 32 disks are £240 incl VAT and delivery for Genuine Porsche items if you know where to ask. There are billions of pad options - Hawk, Cool Carbon, Pagid, Ferodo, Performance Friction etc? Or am I missing something?

P.S 6-pot APs are good, but then so are 6-pot Brembos off the 996GT3 Mk2 996TT (and much cheaper)...

Aren't stoptechs copies of brembos?

AP kit has bigger disk for same money and is race proven, dunno how many stoptech kits are racing (not brembo but stoptech). Standard Porsche disks don't seem up to the task on the Gt3s? They all seem to move to alcon or similar with slotted rather than drilled disks (even though they are cast drilled is the only way I can think of to describe the disks with holes in).

If they are genuine Brembo porsche calipers then fair enough, didn't realise that, I know they used to be but thought they were now making their own copies? If genuine Brembo calipers and you can get slotted disks then it'll be much of a muchness so just get the kit you feel you'll get most support with.

As for GT3 calipers being cheaper than AP? I looked into it for mine and it didn't seem to be the case once you've paid to get bells and brackets made up to fit your car...

Tom - would've listed BMSport if I knew they had an online shop, sorry!

[dan101smith]

Tom - was in Bexleys on Friday, and was peering at the brakes on your car and Pier's too. Have you got 4 pots?

I guess I'm less interested in the £100 difference between the AP and Stoptech kits, more in whether I'll notice a big difference over the standard single piston calipers and OEM discs (with Pagid RS29s)?

[Cheburator mk2]

dan101smith said:

Tom - was in Bexleys on Friday, and was peering at the brakes on your car and Pier's too. Have you got 4 pots?

I guess I'm less interested in the £100 difference between the AP and Stoptech kits, more in whether I'll notice a big difference over the standard single piston calipers and OEM discs (with Pagid RS29s)?

My brother is running a 400+ Bhp supercharged Z3M Coupe with Movit all round. With the Big Reds at the front the way this things stops compared to my Z4MC when it was on stock CSL brakes is unbelievable. Very good resistance to fade on top of the better modulation...

Nathan, I appreciate the reply. Seems that even AP are not up to the task if you are racing - Ring Racing binned all the AP / Brembo stuff in favour of the Alcons. The cost though is steep, very steep. I have only had good experience with Porsche discs and BMW, actually. I thought Stoptech are doing a Movit - buying Brembo and re-badging them, but then I stand to be corrected. If they are copies - then AP is better value for money. Lastly - the cost of GT3/TT calipers - you never know what ebay will throw. I bought the Movit hats + adaptors for my Brembo kit for the Z4MC for the grand total of EUR280 from the guy who makes the Veritas car near Euiskirchen. He offered me GT3/TT calipers for EUR700 for the pair, but since I already had Brembo 4-pots I declined...

[m12_nathan]

No worries, I had a look on the stoptech website and they certainly give the impression that they make their own nowadays.

Sounds like you got a bargain with your setup!

[mikem7709]

Don`t know about the Stoptech callipers but the discs are far better than Brembo. I have Brembo 6 piston Monoblocks on mine and after getting the car supercharged the discs lasted days. The Stoptech rotors weigh slightly more than the Brembo ones but bolt straight onto the Brembo hats and have taken some serious abuse with no problems at all.

Stoptech also offer a ceramic composite front and rear kit now, if I was to do it again, I`d go for these.