Rob Powell

On the back of the recent mass-debate whether AP 6 pot calipers or Alcons or Brembos blah, blah, blah are best is it possible to transfer the existing Subaru 4 pot calipers to the rear and then fit AP 6 pots on the front? has anyone attempted this or is it just not possible or even worthwhile bearing in mind rear braking forces are fairly low?

bob

Not possible, what about the hand brake?

Hoppy

As Bob says, this is not possible and neither is it desirable.

The stronger the front brakes, the easier it is for the rears to lock up. However, most track day drivers fit hotter pads (Prodrive's Ferodo DS2000?) as the standard pads are pants. Dot 5.1 fluid is also a good idea as the rears get very hot indeed, due to almost total lack of cooling.

Fiddling about with brakes in the way you're thinking is a strictly for the experts. Fitting bigger fronts already upsets the balance considerably but it's a tried and tested mod and Scoobs seem to take to it okay. Even so, a really powerful front brake set up will push the standard suspension to the limit and uprating that will improve hard braking performance quite a lot.

Andy Mac made a post on here recently about disabling the ABS on his MY98 Scoob with standard suspension but also the 16in APR 4-pot kit with AP Japan pads. B'stone SO2 tyres. He'd been doing some 100-0mph stops and found that the ABS was tripping in, perhaps increasing the stopping time.

So he whipped out the fuse and tried it without ABS. The back end immediately stepped out and he had a nasty scare. After building up his confidence he tried again but couldn't get within 0.5 secs of the ABS assisted time (just under 4 secs, which is bloody quick!). By the way, Evo tested 14 supercars earlier in the year and the best 100-0mph time was put up by a 911 Turbo at 4.3 secs.

Richard.

PS Andy Mac is a source of much useless but interesting information We've been swapping e-mails since he bought my APR 4-pots when I changed to 6-pots.

I too have been doing 100-0mph stops and on some grippy tarmac at Bruntingthorpe achieved a best of 3.25 secs Andy calculates this at 1.4g and generates enough heat to boil three kettles of water. A normal kettle takes twelve minutes to do this!

We've concluded that my better times than his are not down to the bigger brakes but the improved ABS on MY99/00 cars and my Prodrive suspension. I also have B'stone S02s but on 17in wheels, of course.

PPS For Gawd's sake don't try this at home. It's really scary and more like an explosion than a quick stop. Could turn well nasty

PPPS Andy, how y'doin'?

[This message has been edited by Hoppy (edited 12 September 2001).]

AlexM

Andy,

Thatis absolutely phenominal for a road car. 3.25 Secs for 100-0 is very very quick.

Cheers,

A.


[This message has been edited by AlexM (edited 13 September 2001).]

AndyMc

Hi Richard

I'm fine thanks (but like everybody else I still can't believe whats happened in New York ).
I seem to have got the modding bug now that my warranty has nearly run out (and I thought I was immune)eg vf24 sitting in kitchen at the mo!

Rob
As far as the rear brakes go,like Richard says,the standard rear brakes are more than powerfull enough and have enough fade resistance for road use especially if the pads are uprated.

When used with uprated front kits such as AP's they will get very hot when on track for example but the only problem I have found this causes is a higher rate of pad wear(3/4 of a set of rear pads in one trackday with AP's on the front compared to 1/3 with standard fronts).

Unlike Richards car mine does not have vented rear discs which run much cooler.With this mod I think I would have a set up to rival the very best.
The 100-0 times I can get are very impressive and Richards are just awesome even if you allow for a 10-15 % speedo error.

Andy

PS Hi Bob remember me I bought the 4 pots from your my00.I have since upgraded to Richards old AP 4 pots.Is there anybody I haven't bought brakes from he he.

AndyMc

Hi Alex

It is Hoppy that has managed 3.25 secs,my best is only 3.7 but to be honest Richard is dead old so I reckon he can't work his stop watch properly (I think thats enough smilies)

Andy

bob

Hi Andy
Sold you the std 4 pots and bought the Prodrive Alcon's. Since then have sold the Prodrive Alcons and gone back to STD 4 pots.
Is there any body I have not sold brakes to.

AlexM

Andy,

My car is also a MY98 with AP4-pots..

I find that the excessive dive makes it difficult to brake very firmly.. The weight transfer can't be helping with braking at the rear either.

I think I feel a suspension upgrade coming on

Cheers,

A.

Hoppy

AndyMc, you cheaky bugger!

For the record, the timing of my 100-0mph stops was done by my 16 year-old son (who suffers a severe lack of old age) who can time a kart racing lap to within a couple of 1/100sec of the official transponders. I put my advantage down to superior mashing ability of the middle pedal

More seriously, during those tests my car would stop time after time around 3.3 to 3.4 secs. My time of 3.25 is best the best of several runs under 3.3 secs, with the speedo reading as close to 104mph as possible (correction error).

Andy M8, remind me of your stopping times in the wet. As I recall, they weren't far off your dry times, which is quite incredible. So far, I have not mastered sufficient courage to try that stunt

Richard.

AndyMc

Hi Alex

Mines the same but so long as I load up the chassis smoothly it stays stable enough.It would be nice if there was less diving under braking but I think the standard suspension is just right the rest of the time,besides I have enough rattles as it is!.

I must admit I've had to re-learn how to brake since I've had the AP's.I thought I was good at driving but they've made me realise how hard it is to brake really late from high speed.It's the transition between coming off the brakes and starting to corner that I have the most trouble with,does this give you any probs?Its a good feeling when I do get it right though

Andy

AndyMc

Hi Richard I didn't see your post

I seem to remember it was about 4.3 average in the wet compared to 3.8 in the dry.Its strange because it feels like it takes forever to stop in the wet.

The other thing that was strange was that I managed the same times as the so2's with some part worn continentals which had so much less grip around corners.

Andy