matt b

Today was the big day to have my porsche/movit brake kit fitted. Went to Oxford to have them fitted by Richard Jeal of Jaz tractions brother- Geoff. Had all the boxes opened- all porsche logo'd packaging- it looked the absolute business-especially liked the discs with their patented dual vaine cooling system (kit consists of 310x34mm discs with separate alloy bells and monobloc callipers. latter are from the 911 GT3/Turbo model).

Anyway to cut a long story short- there was no where near enough clearance for the caliper when we offered up the alloy. Now Geoff thinks there may be a mistake in the order somewhere but as it was the first time he'd ever fitted the Porsche kit to a subaru he wasn't sure. Certainly an experiment using some 5mm spacers showed that the alloy was nowhere near fitting.
Ive got a MY99 fitted with a a set of WRX 01 17inch alloys.

Comparing the new much beefier calliper and huge disc in some respects i was not at all suprised there was a problem.
-so guys how does for instance the AP kit get past this?
-Is the secret in the alloy bell as a way of spacing the alloy away from the disc.

Im also thinking that the alloy itself is of the accomodating kind. Any comments on this particular alloy?

Regards
Matt

Dave T-S

MY01 standard alloys are ET55 but this has no bearing on what caliper clearance there will be as the ET is only the relationship between the wheel centre and the hub bearing surface.
The spoke shape largely dictates caliper clearance. Also, as the disc is bigger diameter than standard this pushes the caliper out towards the edge of the wheel, and this is where most wheel spokes start to thicken up again for strength.

The AP 6 pot kit as fitted to my MY01 has 28mm thick discs and a relatively slimline caliper. Your disc is 6mm thicker for a start and I suspect contributes towards a a very thick caliper overall.

Caliper piston size and travel will partly dictate caliper size.

There are wheels out there with a fair amount of spoke clearance but I am not aware of any info in the public domain regarding them.

Spacers are not a good idea as you will have to fit longer studs, plus the standard Subaru wheel locates on a spigot and if you DO fit spacers they should be machined specifically with the same size spigot on them; plus they will alter the wheel offset which will have an effect on the steering geometry.

You may have to give up on these calipers


[Edited by Dave T-S - 2/16/2002 7:24:10 PM]

RON

Matt
I haven't had anything to do with these brakes, but someone said somewhere that it was necessary to fit a 10mm spacer to fit them, it's a bit curious that they won't go inside the 01 alloys, as there is a lot more room in them than some wheels,
Keep us posted.
Ron

matt b

sorry i got the disc dimensions wrong. they are 322x 32mm. Dave i hear what you are saying. the Porsche calliper is a 4 pot yet is very thick. Comparing the AP 6 pots -the two go about the same idea in different ways. the porker callipers pad has a surface area of 78.5cm2, the Ap's with 76 ish i think. as you say the Ap's are longer and slimmer. thats probably where the main problem lies.
I dont want to go down the huge spacer route so we shall see.
It will be a real shame if this doesnt work out as this kit looks awesome.
the guy who fits these has a business specialising in the ZZ1 Corvette muscle car. The workshop was full of these cars and while ive never been a fan of this type of car- you could not help to be impressed by the sledgahammer approach these cars take to performance. 500-700bhp through 2 twin-pipes is a serious sound. anyway all of the cars there had the porsche kit fitted on. Geoff was saying that his co had been through all of the known specialists before arriving at the movits. Several of the owners there could not praise them highly enough.
Ill keep you updated.
Any other thoughts/theories anybody?

SecretAgentMan

It sounds as if U might be in the market for new wheels...

Compomotive has a wheel that's got an enormous amount of space for a huge caliper....the TH-2.
I am running this in 18x8 ET50, and with my 4-pot AP's I've got silly amounts of room left outwards.

/J

matt b

So ap 6's and discs just fit right on do they? no need for any kind of spacers or whatever?

evscooby

Hmm.. Troubles with Mov'it kit. I allready discussed it for my My01 with DaveT-S as it certainly fit without spacers when you use Compomotive MO 8x18 in ET50 or the 7,5x17 5-spoke MO-wheel, but NOT on a standard Subaru MY01 wheel.

My question is.. how much do you need extra and anybody know how much an SPEEDLINE GT-ONE 7,5x18 with ET48 does extra in comparance with an MY01 17" Subaru wheel?? Pete Croney maybe??

Spacers? No, wan't use them on such a car and setup.


Erwin

RON

Matt,
having just picked up my new set of my01 wheels, I have measured the offset, and found that you could fit a three mil spacer to just get the wheel back where it is with earlier ones, I had a set of Brembo's on my car at one point, and the bell on them was 8mm (I think) thicker than the original disc so, a 10mm spacer would not be totally out of the way, like dave said though, they would need to specifically made with a flange so-as to get the wheels dead centre.
Ron

Theo

I've seen a car yesterday with the AP-6pot and the MY01 WRX wheels,..there is even a 3mm space left !

The Move-it calipers which are also Brembo units are almost the same size as the New STi brembo's,....much thicker compared to the AP-6pots ! (has to be, because the disk is thicker.)

That's why Prodrive is bringing a new wheel soon in 18" with a ET43 just for fitting the Brembo's, there is also a 18" P1 wheel available at the moment to fit the WRX wich has a ET46 only in Gold !

I bought the 18" GT-ones recently and asked Pete Croney , if this wheel does fit with each brakekit available on the market for the Impreza,...and he answerd positive abouth that.

matt b

Flange, spigots, offset...youve immediately shown up my embarassingly poor knowledge of all things mechanical.
-Evscooby are you saying that you KNOW the WRX 01 alloy to be no good with the movit kit?
-It seems pritty obvious that the alloy will need to be spaced further away to get these puppies to fit. Ideally i guess you'd want the alloy bell itself to be deeper and therefore to act as a spacer. i doubt somehow that id get that so what guys are you actually saying i insist on (please describe) to do this properly.

-i think that if there hasn't been some kind of error and 10mm spacers are a requirement then I'll give up on them and get my money back. The I'll be back to square one and p*ssed off that i missed Scoobymania's xmas sale.
-i dont like the idea of altering the basic geometry. I certainly am not going to change the alloys as they were a recent purchase.
If i was to theoretically change them and say put 18's on (which im not) wouldn't that bring the tyres out by a similar distance?
-What are peoples views on spacers if done correctly. the car is due to go to Powerstation anway so they could always make the necessary adjustments?

Regards

Markus

Time for me to chip in I suppose.

As some may know I too am going the movit route, well, hopefully! I was on my way up to oxford to see Geoff when he phoned and explained the problem he was having with Matt's kit, and thus said he did not want me to have a wasted journey. I too have the MY01 wheels, on a MY94 WRX Wagon, if you did not already know I'm not about, after spending circa 700 quid on wheels and tyres, to change the wheels, besides I like the 01 wheels.

Why does it happen? caliper and disc bigger than standard, but hey, what do I know.

Geoff said he'd contact Guido @ Movit today (monday) and see what he has to say about all this.

As for the 10mm spacer issue, well, that could have been me, as I was giong to have the 996 kit with 16 inch wheels, but it would have needed a 10mm spacer to fit, and I was not too happy with that idea.

I'd hate to give up the movits, as I've been going on, and on, and on, and on....... about getting them, but if they won't fit then it'll have to be AP 6-pots.

Oh, and on the subject of AP's, matt, you have mail!

Dave T-S

Matt
Wheel spacers are like a big washer and fit over the wheel studs in between the wheel and the hub. I personally would not recommend them because you have to fit longer wheel studs with them and it is a compromise setup that has suspect benefits. It is, after all, a bodge to get around a problem. You are also altering the wheel offset by 10mm or so which is not a good idea as it will affect the steering geometry and feel - the less offset you run, the more the wheels are spaced out and the track increased; and it will probably make the steering heavier.

You cannot easily move the calipers away from the wheel by fitting a different offset disc bell because you would also have to fabricate and fit different offset caliper mounts - the caliper and its mount have to move the same amount laterally as the disc does. Without looking, the disc inner surface is probably not far off fouling the track rod end so this would not work.

I doubt if 18's would help - the STi7 has whacking great Brembo calipers and few, if any, (certainly not the P1 10 spoke alloys) wheels will fit over them - Prodrive have had to develop a brand new wheel - which as Theo says will *probably* go over them.

The bottom line seems to be this - if you want to stick with your Movit brakes, you will have to get new wheels. If you don't want to change your wheels, you won't be able to go with Movit brakes.....

[Edited by Dave T-S - 2/18/2002 9:15:58 AM]

Godspeed Brakes

iTrader: (259)

When we make our discs and bells the disc offset is more than standard discs , Our 335mm discs are 32mm thick , and we have used them with most calipers with no clearance problems , we offset our discs so they are about 2mm away from the track rod end , the dust shield needs removing or they will touch the discs , Making them this way will accomodate any caliper . Cheers , Ian , www.godspeedbrakes.co.uk

Markus

Thanks, I think , Dave. source of much knowledge you are.

I'm trying to find out if the 996 calipers are smaller than the GT3 ones, assume they are, and if so, wondering if they will fit with no problems. Was originally going for the 996's but then decided to upgrade to the GT3's ok so 996's wont be as poncy, but still damn poncy to have the same brakes as a porker turbo

worst case scenario, will go for AP 6-pots, providing of course they will fit under MY01 wheels? anyone know this for sure?

scoobymike

Markus

if the MY01 wheel has 55mm offset there's no way to fit them over the monoblocs. On my mates Scoob he uses wheels with 45mm and the GT3 callipers fit without any problem. On my EVO I can even put a finger between the calliper and the wheel.
Richard should be able to sort this out you would be the first one where the kit doesn't fit. Don't let yourself put off by this, AP would be a step back. You know the facts.

Cheers

Mike

Markus

Mike,
thanks mate, thought you'd pop up on here at some point

I'll wait and see what richard/geoff say. i'd love to stick with the movits, and more so with the MY01 wheels.

Matt, sorry for hijacking your thread

evscooby

Matt B - As confirmed by specialist ScoobyMike, it will not fit a standard MY01 wheel with huge offset ET55.

ScoobyMike - Can you say anything about SpeedlineCorse wheels in 7,5 x 18 with ET48?? ET-isn't saying anything, but perhaps you know some Movit-friends who've tried??

Thanks and regards,


EVSCOOBY (HOLLAND)

Markus

OK, you guys know the movit kits, so maybe the numbers 4m6 (GT3 kit) and 4m5 (996 kit) will mean something to you.

will the 4m5 calipers fit a MY01 wheel?

matt b

Markus
No mate, you go for it as we're both in the same boat after all. Ian's way round this sounds promising.
Mike-good to hear from you. Are you saying that an ET55 alloy just will not fit a GT3 calliper? I really cant change the alloys so thats not an option. As i said earlier when i unwrapped the kit i was very very impressed. It would be a real shame if this kit just wont fit a normally shod 17' scoob. I think there are many more potential customers out there if we can sort this out.
Cheers

Markus

Thanks Matt.

I'm with you in that I got the MY01 wheels as i like them and I am not going to change them, unless someone will swap me a set of 17's and new tyres, which will allow the movit's to fit.

I want these brakes because they look good and are meant to perform amazingly, as scoobymike has said in the past, you ever heard a porker driver complain about thier brakes.

I digress. My theory was to get them fitted and prove they fit and work and are an alternative to other systems out there, thus I want this kit to fit, end of story.

OK, so I'd be resigned to AP 4 or 6 pots but I'd rather have movits.

guess we'll just have to wait and see.

matt b

Markus
I dont think the 996 calliper will fit either. Although it will be slightly smaller the fact that both are 4-pts makes the design very chunky rather than the longer slimmer appraoch adopted by AP. like i said earlier the alloy was absolutely nowhere near fitting. the 5mm spacer made no difference. i suspect that Geoff either was trying to fit it incorrectly or a part of it was wrong (eg the fixing bracket for the calliper) as it was just so far out.
Ian- can you explain how you off-set the disc?

Markus

am assuming it's the width of the wheel that is the problem?

Anyone know what 17 inch wheels would fit over the brakes? and would they fit an impreza.

Mike, what wheels does your buddy have on his scooby?

[Edited as I ased about 18's being a solution and Dave had said probably not - doh! I should learn to read properly!]

[Edited by Markus - 2/18/2002 11:55:06 AM]

evscooby

Matt B / Markus,

Width of wheel does not say everything, or even nothing as you like because there are wheels with the spoke-design inside the wheel and also ones with spokes at the edge or even near out the wheel.

It is a combination of width (the same wheel design in a bigger width [ more weight either :-( ] would help, but then you also have the offset (ET).

I think that IAN GODNEY ment wit Offset the disc, that the two parts (Hub inside disc and between car and wheel) can be in center of the disc, but also with offset, in- or outside placed (in mm's). Therewith you must change the bracket (but that is an non standard part for GodSpeed as for Mov'it) so they can change that to the matter of room you have.

Maybe there are better explainations here, but this was mine!

EvScooby

(also trying to get sure that Mov'it will fit on MY01 / GT1 in 7,5x18 and fully agree with Markus statement, but not changing
wheels as the GT-ONE is leight and beautifull - Spacers, NO but as far as I know Movit, read ScoobyMike's comments on LancerBBS etc. it must be solved!)

Markus

thanks mate

as said, think richard @ Jas and Guido @ movit will want to fix this one, as if matt and I can have the brakes under standard MY01 wheels then it could mean a bit of business for movit brakes in the scooby world.

scoobymike

Unfortunately it won't be possible to fit the monoblocs either GT3 or the "standard" 996 callipers in connection with a 55mm offset wheel without using spacers. The "stubby" design is one of the advantages of this calliper compared to the long-shaped AP ones. AP needs this long shape and 6 pistons to achieve almost the same pad surface as the monoblocs already achieve with 4 pistons. This increases weight (3kg for the AP6p and only 2.3kg for the GT3 one) and the possibility of the calliper to expand under hard braking causing the pad not being equally pressed on the disc. This tendency is minimised by the pad shape and the monobloc design of the Porsche callipers. Remember you can generate around 120bar under hard braking so this forces to calliper to expand!
I can't say which other wheels fit over those callipers on the Scoob. I only know on my mates wheels with 45mm offset no problem. Just check out the provided link so you can see it with your own eyes:
http://www.movit.de/rahmen/subaru.htm

Cheers

Mike

Markus

Thanks mike.

don't suppose you know what size spacer would be needed do you?

Dave T-S

As mentioned in my earlier post, ET as such has no bearing whatsoever on caliper clearance. The ET is only the relationship between the wheel centre line and its mounting flange.

Wheel spoke SHAPE dictates caliper clearance, (and to a certain extent wheel diameter, not width) and this is different on all wheels.

Wheel brand "X" with ET55 may have exactly the same, or more, or less caliper clearance than wheel brand "Y" with the same ET.

You can of course give more caliper clearance by using spacers, and this will DECREASE the offset as a by product - but with the attendant problems as previously mentioned.

As to the AP 6 pot caliper design leading to possible caliper spreading under pressure, well I think that might come as a surprise to AP.....

scoobymike

Every calliper spreads under heavy braking. So tell me what's stiffer a one piece design or a two piece design needing two heavy steel bolts? Also AP offer monobloc callipers but only for racing purposes and without dust seals AFAIK.

Mike

Dave T-S

Well.....let's not get into an argument about caliper spread, as that's kinda off-topic, and probably not too relevant

I don't think two piece calipers are a disadvantage on road cars, and the AP one currently has the big advantage that it will do what the Movit won't......fit under the wheels!

evscooby

Dave, That really is an important one!! ;-)

EvScooby!