Astra mk2 GTE with Calibra turbo brakes questions

[Vinci]

Hi guys,

I can get a pair of Calibra turbo brake calipers and want to fit them on my Astra mk2 GTE 16v. I now have 256mm X 24mm discs.

The calipers I can get in sizes for either 284mm X 24mm discs or 288mm X 25mm discs.

Which would be a better choice?

[Gordo]

AFAIK, either is incompatable with your brakes - you need to have matching disks for the calipers.

[DarrenH]

the answer to which is better choice is "biggest rotor you can fit under your wheels" if you have 15" then the answer is 288

[Gordo]

Darren, i think he's just got an option on the calipers.

[Nemesis]

Calipers bolt straight up obviously

Disc wise you can

a) Use the standard disc (284/288) redrilled to 4x100
b) Use Lotus discs that came in 288mm 4x100
c) Possibly use Fiat Coupe discs, I forgot the specs on these but it's a popular choice (?)

[Vinci]

Thanks for the replies guys!

I can choose between the calipers, someone is selling a bunch of them here... And the discs are yet to be chosen as well... I've got 15" mk3 GTE wheels, so 288 should then be no problem I guess...

Lotus discs, good idea!

[Violet]

What car is the Lotus discs from?

[GreddRob]

What car is the Lotus discs from?

Lotus Exige
EBC GROOVED BRAKE DISCS REAR LOTUS Exige 1.8 2001- | eBay

[Vinci]

Excellent! Although the price is rather firm... But they need no drilling etc....

Vauxhall Car Parts Brakes

[DarrenH]

LMF sell 288mm brake upgrade for 300 euros. but that is calipers, carriers, disks (drilled to 4 stud), pads and spiggot rings. i cant find it on the website but i know they also supply just 288mm disks drilled to 4 stud (as if you were replacing warn disks for their kit) for around 70 euro

[Vinci]

Mean this kit?
LMF Vauxhall - The Vauxhall Parts Specialist...

Nice!!!

What surprises me a bit is that the kit is not suitable for the Calibra V6/Turbo, but that must be because it is 4 stud right? The calipers shouldn't be the limitation.... I just wonder why they didn't write:"Kit suitable for....with other discs..."

[Vinci]

How much sense would it make to upgrade to EBC or Black Diamond grooved discs and EBC redstuff pads?? It costs a heck of a lot more!!

[DarrenH]

What surprises me a bit is that the kit is not suitable for the Calibra V6/Turbo, but that must be because it is 4 stud right?

maybe because they already have 288mm brakes ?

but maybe now they sell actual 4 stud disk with the kit, when i bought mine from LMF it was 5 stud disk re-drilled to 4 stud.

[thedondy]

How much sense would it make to upgrade to EBC or Black Diamond grooved discs and EBC redstuff pads?? It costs a heck of a lot more!!

i did on my cav sri with v6 fronts, fitted black diamond combi discs and redstuff pads.
seem to be a good job

[Vinci]

Apparently they still redrill... But the whole kit for under 200 quid, not bad!!!

VAUXHALL NOVA CORSA ASTRA 288MM V6 BRAKE UPGRADE KIT | eBay

[richie00boy]

I would get the 284mm setup as the 288mm setup uses a bigger piston in the caliper which spoils the feel/travel of the pedal.

[Vinci]

I guess I'll have to find that out for myself then cause I have already bought a kit last night...

If it really feels crap I can sell the kit quite well here in the Netherlands with a bare minimum of loss....

[Vinci]

I would get the 284mm setup as the 288mm setup uses a bigger piston in the caliper which spoils the feel/travel of the pedal.

So far I can only agree with you, although I am not quite convinced the system is blead well enough... I always bleed brake systems using a spare reservoir cap with a bicycle inner tube connected to it, then pump it up to 1 bar and that gives some time to bleed each brake. Only the rubber seal on the cap is not so great any more, so it leaks a little bit giving too short time of pressure to bleed properly....

It brakes quite powerful, but only the last 20% of pedal travel....

[jayc20xe]

I've got a bigger master cylinder on my mk3 from a cav v6 it's a 23mm the standard is 22mm!

I also have a spare one laying about if your interested? Im not sure if it fits a mk2 maybe someone could confirm then drop me a pm!

[Vinci]

Interesting....might take you upon that offer! Well yesterday I gave it another shot to bleed the system and for a brief moment I thought I was in luck....

I put the car on jack stands, removed the wheels so bleeding was a piece of cake. One Caliper at the front gave tons of air bubbles after some taps on it with a chunk of wood, so I shut the bleeding nipple and started the engine. Perfect feel and travel at the pedal! I always bleed by pressurizing the fluid reservoir with one bar of pressure with a bicycle inner tube on the mouth of the tank... Always works really well....

But after a while it was back to flooring it to the bottom... Argh....

Now I also have placed Goodridge braided hoses and I think I perhaps have a leak somewhere....????

How can I confirm that, I was going over all joints with my finger and it didn't feel wet, but perhaps it is just sucking in air? Maybe the bleeding valve itself is screwed??

How much air is needed to give that pedal to the floor feel??

[jayc20xe]

Hmmm could be taking air on somewhere, most threads I have read on 288's all comment on the bad pedal travel even after extensive bleeding! I myself upgraded the brake lines too goodridge without Amy change at all.

Does seem a little strange that it was good then went bad!

[Vinci]

That's what puzzles me, it was really fine, even after squeezing the pedal a couple of times, left the engine running, so there was a vacume on the servo....

The box with the calipers arrived in pretty bad condition and this particular caliper had a bent bleeding nipple. So I contacted LMF and they were really helpful and sorry, so they promised to send two new bleeding nipples and four new sliders. The nipple I am using now is a brand new one from a local parts shop and it did look like a 100% fit.... but who knows??

I will wait until the new nipples from LMF arrive and have another go at bleeding the system. Maybe if I can get some spare time I will lock the banjo fitting on that side with an M8 bolt and bleed it and see how the pedal travel is without this caliper in the system....

[Gordo]

There's also a good chance the master cylinder its the problem. If you hit the pedal hard, is it hard?
Sometimes, when fluid isn't rplaced as aften as it should, it'll absorb moisure which can cause rust and pitting in the master cylinder and/or gunge or debris to stop the seal sealing correctly and consistently.
If the bleeder(s) were the problem, the fluid loss would be very evident, both as a drop in the fluid level and as a wet area somewhere. - nothing showing below the caliper or on the wheel, from leaking caliper seals, either?
If air was simply getting into the system, it would show as a small increase in the fluid level in the reservoir - either way, marking the level when it's good, with a pencil, would give some idea.

[Vinci]

The MC is less than a year old, original 22,2mm, I replace fluid every year.... that can't be it... Plus it was fine with the original front brakes...

Marking the level is a very good idea indeed!

While bleeding the brakes yesterday it was very obviously just that one caliper with the replacement nipple that had terrible air bubbles, I am not talking bubbles like a soda drink, I am talking massive pea size bubbles and loads of them... After that it was good for a moment...

Maybe the caliper itself is screwed?

No wet places spotted so far....

[Gordo]

It's unusual, but it's possible for seals to be damaged, or fitted incorrectly, and act like 'flappers', one way valves that let air in while still holding the fluid in, so as the piston is pushed out and retracted, air works it's way in - certainly sounds like it

However, this is usually partially due to a blocked relief/replentishment port in the master cylinder that allows fluid into the master cylinder bore being blocked and air being drawn into the system to make up for the additional volume needed as the pads wear.