Classic Alfa Forums

Ive read up on the various front brake conversions for outboard suds and 33's but it's likely I'm sticking to my 13 inch retro rims, or 14 inch max, so 2 questions

1. I can't find many options for grooved standard sized vented discs, just Tarox and some dodgy looking OMP grooved and dimpled - anyone come cross any other options recently

2. Has anyone considered or done just a caliper upgrade on the standard sized disc. Not an expensive after market, but a caliper from another model or make readily available, but again under standard rims?

I'm upgrading the master cylinder and fitting a bias valve so that will help, but more bite would be good.

Thanks

I often use the ebc catalogue to cross reference disc sizes, heights etc.

Its often led me up the Fiat route, being 4 x 98 still helps too,

certainly for 15's, i can use stuff such as fiat coupe, maybe there is a little vented disc for the Punto, or a sporting model perhaps? just something with equally diddy rims! lol!

Punto 1.8 16v

257mm vented, 40mm height, same as 33 16v iirc


any good, right tracks?

petrolhead wrote:Punto 1.8 16v

257mm vented, 40mm height, same as 33 16v iirc


any good, right tracks?

257mm discs were used on a lot of lancia stuff too, maybe a cheap search option?
still 4x98 of course

The 16v discs are 239mm and 46mm depth to hub?

right you are tim, right you are!


after speaking tonight, are you definitely sticking with 13's, not a chance of 14's?

Slightly off track unless you go to larger wheels. I just today made steps to upgrading my 33 brakes.

I bought some second hand Commodore VT twin piston calipers for $80 and trial fitted them. These are fitted to large 6 cylinder sedans and are the same as V8 Commodores only lacking the fins.

They bolt straight on but need spacers or washers between the caliper and hub. The discs will come from a Mitsubishi Magna, I had one from a wreck at home but the diameter is too small but I'll get one off a later model tomorrow that will be around 284- 279, Magna discs need the 4x98 pattern drilled or Alfa 155 V6 discs may be an exact fit but I need to look into things more and do some measurements.
These mods have been done before in Aust. and I'm following what other people have done but people have added there own twist on parts used. Here's some pic's of the calipers fitted and I'll update what happens with them.

Forgot to mention I will need 16 or 17 inch wheels. Some say 15's work but I'm not sure if they used the older model single piston calipers, still a huge upgrade but wont be using them. These pic's don't do justice showing how much bigger they are and there lighter.

Now thats a great find that is Ricky.

I don't think we get anything like that here as an equivalent model, and the caliper themselves look largely unfamilar to me personally too.

The washers thing might not be the same once a new disc is placed, for example, the 33 16v discs is 239mm diameter and 47mm hight, whereas the 155 V6 is 284 Diameter but only 44mm height, so does this height difference makes it sit at a different centre within the caliper?

the 155 V6 disc sounds like a good option, and are still available in grooved, dimpled, drilled etc too, yummy!


Next Question, can you get me some more?

perfect for my sud if i stick to keenly sized disc for my 15" Revo's to fit over.

any chance you could get some sort of measurement from centre of hub to widest point of caliper please?


thanks in advance

adding to that

i found these Ricky,

http://www.ebay.com.au/itm/VT-VX-VY-VZ- ... 456&_uhb=1


are these correct?

any idea how much shipping might be if i bought them through you, just in case they won't ship to the uk (i have asked the question, just waiting for a reply)

cheers

Yep that's the calipers. I'm a newbe at shipping, I think I have to weigh them to know.

You did get the Vauxhall VXR over there same as the Holden Monaro here. There's awesome up grade kits for those on ebay with prices to match. I theory they will bolt straight onto a 33. The catch I haven't worked out yet is what discs to use. I know a later model Magna disc will work getting the stud pattern drilled out or these 155 discs that possibly might need machining to a smaller diameter http://www.ebay.com.au/itm/Alfa-Romeo-1 ... e85&_uhb=1

hi ricky

i just edited my first reply on the disc thing, just glance back a mo


i have a feeling that the uk VXR got some monster 4 potters for front calipers?

Ok I took some measurements I got 170mm to the outside of caliper, 145mm to outside of pad and 8mm spacers caliper to hub or less? but take these measurements with a grain of salt I did it quickly at night. I might find something new working on it tomorrow.

The Holden and Vauxhall are the same car and just looking at the hub bolt holes they look the same and the six pot brembos have an adapter to fit, original 4 pots may be the same. The calipers I got are the same as the V8 just with cooling fins.

Commodores sit at wreckers in the hundereds it's no problem getting them. At YouPull it wreckers 2 pots are all $80 a pair.

The 8mm spacers are to centre the caliper over the disc edge yes?

This is shaping up nicely into a how to thread, before long i think it might be better in the modifications lounge Ricky.

If you seen this through successfully, which it appears you will of course, then that my friend is a great mod and method, and deserving of a permanent place in the Mods you can trust kinda list!

so don't be surprised when you find it moved!

That's a cracking upgrade......shame I'm running go kart wheels...

Ok back again, it's seem I've become a guinea pig. It seem everyone on a thread on ABB forum that got me started on this is using the older single pot caliper and a modified Magna disc, all smaller than what I'm doing.

Only one guy has VT Commodore calipers and he bought the car like that and does not know the story of how it was done. I actually talked to him about his car at a local car show but I didn't notice his brakes.

I think what I'm doing will be easier but I'm going to need a 16 inch minimum wheel.
Doing the sums I need a 287mm disc to use the whole Commodore brake pad. I cant find a disc to use with a correct centre bore and stud pattern but if I use a 155 V6 disc at 284mm half the 3mm difference and lose 1.5mm off the top of the Commodore pad, know what I mean.
I think to make it an easy mostly bolt on conversion it's a good compromise using less pad area. When taking into consideration having a bigger disc diameter, twin pistons and 40% more pad surface the brakes will still be awesome.

Also just playing around putting it together with the standard disc I needed 5mm washers to space the caliper carrier in the centre of the disc. The standard disc height is 46mm the 155 disc 44mm, it's not much difference and only plus or minus a washer or two. Also the caliper slides on the caliper carrier so I think getting the caliper positioned over the 155 disc is no problem.

I did try putting a wheel from my Sprint on and the wheel centre bolts (remember 3 piece wheels) hit the caliper. I tried another 15 inch wheel with +35et and it did fit without touching but that wont fit in the fenders. So I think a modern one piece 16 inch wheel will fit "I hope" because to me they look the most in proportion with the car ?

This picture shows the different pad size. Taking 1.5mm off the top of the Commodore pad looks feasible. I'm ready to buy new Commodore pads and see if a 22mm disc will fit in the caliper. I don't see a problem though and then I'll buy 155 discs, Your right Shrew there's some awesome 155 discs around.

Yep, Great being a guinea pig isn't?


Now crack on, we're waiting! ha ha!



Plus, if you think a 15" will fit over the caliper and use of a 287mm disc, i am even more interested!


Might not be ideal, what about slotting the caliper bracket mount hole outwardly so that you can bring the caliper in towards the centre by a couple/few mm?

you could plug weld or bush the slot once happy with the fit to return it to round and single position only, and that would allow you to use the full pad, and maybe even sneak it inside a smaller wheels perhaps?



On the subject of availability of the same caliper here, i've drawn a complete blank


we simply did not get the monaro/vxr in any number at all, so spares are so very scarce and likely sourced from your side of the waters anyway.

so again, i'm afraid ricky, this project lands firmly back at your doorstep! ha ha!


great work though mate, keep it coming...

I'm also waiting to see what happens.

I too want to use my 15" wheels on my racing sprint which has front suspension and brakes of the 16v.
Those brakes are rubbish for the track where you need late and efficient braking.

I always heard that Vauxhaul V6 calipers would do even with standard discs, but I wont swear on that

Keep us posted mate

We need to stop before we go :p

Yep I'm a pig and a gluten for punishment Good thinking about elongating the holes, I think I can handle that but I'll get the discs in my hands first to see how much I can go to the centre of the disc and check for any issues.
I could take second hand calipers off cars myself with hoses and ship them but lets see how it goes together first, I have no idea on shipping costs either.

You know as common as Commodores are like flys here I've never been into the whole Holden vs Ford culture we have, it could be the bogan hoon image and the fact people like stealing them for ram raids and getting into police chases, that's because there powerful rear wheel drive cars.
But just looking into the brake side of things there's so much available for them to upgrade. I think you racer guys with the work shops you have could come up with some great setups cheaper than GTA and other parts. I know people do some awesome and expensive things over there, I've been googling.

I just bought these pads. I know there cheap I could have spent a few hundred but for the purpose of getting it up and running they will do. Note the larger pad surface.
They will be here quickly.

Some other nice pads http://www.ebay.com.au/itm/131153924666 ... 1423.l2649

The pads I bought for now http://www.ebay.com.au/itm/150890611472 ... 1423.l2649

Supercharged16v wrote:I'm also waiting to see what happens.

I too want to use my 15" wheels on my racing sprint which has front suspension and brakes of the 16v.
Those brakes are rubbish for the track where you need late and efficient braking.

I always heard that Vauxhaul V6 calipers would do even with standard discs, but I wont swear on that

Keep us posted mate

We need to stop before we go :p

15 inch wheels or the single wheel I have that fitted are so close to not fitting. 4 out of 5 different wheels I think would not fit. What about a 16 inch with lower profile tyres?

^^ But I might get the caliper in some more!!

No mate, sticking to 15's

16's are a b***h getting slicks tyres for

Well regardless, I need to work things out. I cant race it like this, its bloody dangerous when the brakes get hot.

Chris it's the v6 calibra 284 calipers you want with fiat coupe 284 disks , there is one v6 calibra that had 288 disks , so you need to measure. These will go in 15" wheels! BUT the calipers weighs a ton

Doesnt matter mate, its not as if its on the wheels spinning.

5 kilos isnt gonna make much difference

Got anything in mind ? Cant find this stuff locally, never seen a V6 calibra in Cyprus, ever

They mite be on vectra's as well? But they are meant to be a straight bolt on

Volvo 240 4 pot calipers, heavy but bolt straight on with a smaller disc "apparently". Who the guinea pig ?

http://www.ebay.com.au/itm/SBS-Brake-Ca ... 860&_uhb=1

Alfaholics do some really nice/expensive stuff for the 105 series, maybe it could be made to fit?

http://www.alfaholics.com/race-performa ... ts/brakes/

one word of caution guys that may have been overlooked, as i've not spotted any reference to it yet.

the calipers you intend using, make sure they are suitable for a disc of very similar thickness.

so, if you are thinking of using the fiat coupe discs which are 22mm thick when new you need to make sure the replacement caliper uses a similar thickness disc in OE spec.
reason being is that if there is a big difference then the pad can fall through the gap between the pad carrier and disc.
this is what i came up against when using the nissan 4 pot calipers which were meant to be used with 30mm thick discs. one track day and the pads were in danger of falling through the gap, logn way short of being worn out.

i'd suggest that no more than 24mm (2mm thicker) discs as standard are considered when using any different calipers.


otherwise, i'm very keen to see someones elses findings

Here you go. A good list of setups
http://www.alfa-pages.co.uk/viewtopic.p ... sc&start=0

KevJTD wrote:one word of caution guys that may have been overlooked, as i've not spotted any reference to it yet.

the calipers you intend using, make sure they are suitable for a disc of very similar thickness.

so, if you are thinking of using the fiat coupe discs which are 22mm thick when new you need to make sure the replacement caliper uses a similar thickness disc in OE spec.
reason being is that if there is a big difference then the pad can fall through the gap between the pad carrier and disc.
this is what i came up against when using the nissan 4 pot calipers which were meant to be used with 30mm thick discs. one track day and the pads were in danger of falling through the gap, logn way short of being worn out.

i'd suggest that no more than 24mm (2mm thicker) discs as standard are considered when using any different calipers.


otherwise, i'm very keen to see someones elses findings

Kev that's a good a god point about disc thickness, I had thought of that but you only just made me go check. For the caliper I'm using the Commodore disc is 28mm, the outside pad mostly stay fixed in one spot "mostly" and the pad on the piston side moves the most.
I just tried a 33 disc that's been machined down to 19mm and the half worn Commodore pads and there's no chance of a pad falling out. I think the pad that moves the most still has 4mm to go till it could come out. The next thing is will a piston pop out, it doesn't look like it it looks like they go deep into the caliper but I'll check closely when I can. It's possible when pads are very low the disc could touch the caliper carrier and it's possible I could grind off a wee bit from the carrier. Also I'm prepared to replace pads at 75% worn.

John that's a good thread I hadn't seen before, still need to read all of it. There's a few bits of false info but using a 146 disc on a single pot Commodore caliper instead of all the trouble of modifying a Magna disc is a good one. It's a smaller disc and there's one piston less pad surface but that's still an epic upgrade for me to fall back on.

Someone said the later twin piston caliper was overkill, if I can make it fit the car I don't think so, I'm still going to try.
A few points, the single piston Commodore caliper is huge "the actual piston" but the two smaller pistons on the later model works out around the same size and there's the bigger diameter disc and more pad surface.
The single pot caliper is much lighter than the 33 caliper.
The big twin piston caliper feels the same weight of the 33 one.
Also I was planing to use a 16 inch wheel all along. If some of you are sticking to 15 inch buying the single piston Commodore caliper and 146 disc is an epic upgrade that mostly bolts straight on.

Actually looking again at the 19mm machined 33 disc in the twin pot caliper. I'm looking at the caliper and disc out of the car. When the caliper carrier and disc are bolted in there's no chance of the disc touching the carrier and even less chance of a pad falling out. So that's something less to worry about for me.