Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: JimmyR on 10 January 2019, 21:17:06

Title: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 10 January 2019, 21:17:06
Hi all!

I'm struggling to get much reliable info online. Basically the thing that has always disappointed me in the 'mega is the brakes. I have a 2005 Astra Turbo that has been written off (Cat N) and I'm planning to scrap soon. I've always loved the brakes in that.

I'll keep the wheels and tyres to use on the Omega, but is there any chance of using the brake calipers? Or would there be no benefit?

I believe the Astra has 308mm discs on the front and the Omega has 296mm discs, but I can find scant other concrete information. I don't have the two cars together to compare right now, and I thought someone here might know. If not, the Astra goes to the scrapyard on steel wheels. Shame for a fundamentally OK car, but it's not worth spending the money to sort it out

Thank you
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Doctor Gollum on 10 January 2019, 21:23:49
Cat N could probably pass an MoT... not fixing it is plain lazy if fundamentally ok ???

No the brakes won't fit. Easiest option is to fit the front callipers from an early base model Monaro/Pontiac GTO... same sized discs as the Omega and same fitting for the calliper. Anything more involved and you're talking £££ and effort. ;)
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: zirk on 10 January 2019, 21:32:23
Very much doubt the wheels will fit, they could be persuaded with some spacers but that could mess things up.  :-\
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 10 January 2019, 21:38:30
Cat N could probably pass an MoT... not fixing it is plain lazy if fundamentally ok ???

No the brakes won't fit. Easiest option is to fit the front callipers from an early base model Monaro/Pontiac GTO... same sized discs as the Omega and same fitting for the calliper. Anything more involved and you're talking £££ and effort. ;)

It did pass the last MOT as a Cat N, but now it has more faults. It's not rusty and the engine and gearbox are good, are what I meant.

It's in a shabby condition, reports an emissions fault (although I've put it through the last few MOTs like this, just turning the light off before the test), it will need some suspension work for the next MOT and one headlight mysteriously stopped working a few weeks ago. I have changed the bulb, but no difference.

At the same time I got a crazy bargain on a car I've wanted for a while, so I've replaced it already
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 10 January 2019, 21:42:00
Very much doubt the wheels will fit, they could be persuaded with some spacers but that could mess things up.  :-\

They do fit - I've already used the car with identical wheels. This will just be a spare set to use the tyres up, since they're good
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Andy B on 10 January 2019, 23:48:55
..... Basically the thing that has always disappointed me in the 'mega is the brakes.  ....

I always found an Omega's brakes to be pretty good .... managed to haul 1750kg to a halt  ;)
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Raeturbo on 11 January 2019, 00:45:50
Brakes are fine in my opinion just need to fit good expensive pads which is a lot easier than changing callipers etc just gone through the same thing with the Evo since I ungraded. Carbotech XP10 are stopping it now if I can stay in the seat😂 mind you they should be good at over £200 just for the fronts🙀
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 07:21:27
Maybe I’m just used to cars with much better brakes then. They feel absolutely terrible to me! I have a Mercedes ML from the same era and that’s obviously a heavier car but the brakes feel better and seem to stop it better. I drive Class 2 trucks that don’t feel much worse than the Omega!

I have bled them and it improved them, but not as much as I had hoped it would
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: tunnie on 11 January 2019, 10:15:55
The pedal is progressive, allowing smooth braking, due to type of car it is. Omega was always aimed at motorway mile muncher and allowing a smooth drive.

Stamp hard on them and it stops, MotherT always said her Omega brakes were poor, until I demonstrated that stamping on the pedal as per an emergency it stops bloody quick!

3.2 here, no complaints with brakes.
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: polilara on 11 January 2019, 12:34:25
The pedal is progressive, allowing smooth braking, due to type of car it is. Omega was always aimed at motorway mile muncher and allowing a smooth drive.

Stamp hard on them and it stops, MotherT always said her Omega brakes were poor, until I demonstrated that stamping on the pedal as per an emergency it stops bloody quick!

3.2 here, no complaints with brakes.

Is it really so that there is "Emergency Mode"?

I asked this in topic below but,
« Reply #12 on: 28 December 2009, 12:53:44 » (Andy B):"No variation of Emergency Brake Asssit on an Omega."
https://www.omegaowners.com/forum/index.php?topic=74340.0;all

Did he mean that the pedal is not "Progressive"? Perhaps language problem for me only. However, I am not happy with the brakes of my Omega, my Astra J has much better...

Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Doctor Gollum on 11 January 2019, 13:15:54
Decent pads and fresh fluid make a world of difference...

Trouble is very few people/garages actually bother to get the old fluid out of the calipers, so you only end up with alot better rather than the best it can be...

Even Police Omegas have standard brakes, so they are clearly up to the job  ;)
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 13:30:02
The pedal is progressive, allowing smooth braking, due to type of car it is. Omega was always aimed at motorway mile muncher and allowing a smooth drive.

Stamp hard on them and it stops, MotherT always said her Omega brakes were poor, until I demonstrated that stamping on the pedal as per an emergency it stops bloody quick!

3.2 here, no complaints with brakes.

To the first point, I don’t think that that is particularly the case.


And if everyone else has good brakes, it must just be mine that are rubbish
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Doctor Gollum on 11 January 2019, 13:34:01
Clearly not driving it properly  :D
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Keith ABS on 11 January 2019, 14:50:54
 Poor quality pads?
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: polilara on 11 January 2019, 15:16:28
The pedal is progressive, allowing smooth braking, due to type of car it is. Omega was always aimed at motorway mile muncher and allowing a smooth drive.

Stamp hard on them and it stops, MotherT always said her Omega brakes were poor, until I demonstrated that stamping on the pedal as per an emergency it stops bloody quick!

3.2 here, no complaints with brakes.

To the first point, I don’t think that that is particularly the case.


And if everyone else has good brakes, it must just be mine that are rubbish

Is it progressive?
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 17:04:57
The pedal is progressive, allowing smooth braking, due to type of car it is. Omega was always aimed at motorway mile muncher and allowing a smooth drive.

Stamp hard on them and it stops, MotherT always said her Omega brakes were poor, until I demonstrated that stamping on the pedal as per an emergency it stops bloody quick!

3.2 here, no complaints with brakes.

To the first point, I don’t think that that is particularly the case.


And if everyone else has good brakes, it must just be mine that are rubbish

Is it progressive?

It is, I suppose. Before I bled the system it wasn't, but you'd expect that!
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 17:06:39
Clearly not driving it properly  :D

I'm not ruling it out!  ;D

And I've had a thought about what you said about scrapping the Astra, so today I decided to look for the headlight fault. Turns out that I'm an absentminded idiot and there's no problem with the headlight wiring - I changed the wrong bulb  ::)

So yeah, I suppose it is too good to scrap really, even with two dented doors. I'll make an effort to find a buyer
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 17:10:58
Poor quality pads?

I'll have to assume this and change them. I'll have a look in the history to find out what they are and when they were changed. They've been on the car since before I bought it in 2018.

They just feel very weak, to be honest. Even with a lot of pedal pressure it just doesn't seem to stop urgently. The pedal feels a bit light too. Not exactly spongy.
It is however the only Omega I've ever driven so I don't know if it's like the rest and I'm just being paranoid
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: TheBoy on 11 January 2019, 17:12:39
Properly maintained, the Omega on standard GM parts (pattern standard brakes for the Omega are universally shite) can fire the ABS at 130mph in the dry with good premium tyres 235/45/17.  In addition, they can handle 10 x 100mph to near standstill in the time it takes to get across Milton Keynes.  Granted, they are spent after the latter.

To me, that means the brakes are perfectly fine for road use.

They need work for track days to prevent overheating (and track pads)
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: TheBoy on 11 January 2019, 17:13:53
The Omega needs a lot of pedal movement. If you're used to Fordesque fart-and-it-locks-up shite, it will be an unusual sensation.
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 17:23:55
Properly maintained, the Omega on standard GM parts (pattern standard brakes for the Omega are universally shite) can fire the ABS at 130mph in the dry with good premium tyres 235/45/17.  In addition, they can handle 10 x 100mph to near standstill in the time it takes to get across Milton Keynes.  Granted, they are spent after the latter.

To me, that means the brakes are perfectly fine for road use.

They need work for track days to prevent overheating (and track pads)

I'm going to guess that mine are rubbish pattern parts then. Problem solved, probably.

I'll search for Genuine GM (or whatever it's called now GM doesn't own Opel)
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: aaronjb on 11 January 2019, 17:25:07
And I've had a thought about what you said about scrapping the Astra, so today I decided to look for the headlight fault. Turns out that I'm an absentminded idiot and there's no problem with the headlight wiring - I changed the wrong bulb  ::)

;D ;D

I laugh because I spent quite some time (including getting the meter out and fishing around in the fuse box) trying to work out why the headlights weren't working on a BMW 118 .. until I realised that they do nothing unless you turn the ignition on  :-[ :-[ :-[
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 17:26:01
The Omega needs a lot of pedal movement. If you're used to Fordesque fart-and-it-locks-up shite, it will be an unusual sensation.

I don't think that's it - I spend most of my driving time in old Vauxhalls, 4x4s, vans and trucks!

I wonder if maybe I've got some particularly rubbish pattern pads. Probably a case of me overthinking it and jumping to a silly conclusion instead of finding the most sensible and likely one
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: JimmyR on 11 January 2019, 17:28:50
And I've had a thought about what you said about scrapping the Astra, so today I decided to look for the headlight fault. Turns out that I'm an absentminded idiot and there's no problem with the headlight wiring - I changed the wrong bulb  ::)

;D ;D

I laugh because I spent quite some time (including getting the meter out and fishing around in the fuse box) trying to work out why the headlights weren't working on a BMW 118 .. until I realised that they do nothing unless you turn the ignition on  :-[ :-[ :-[

Today I really feel that I've let not only myself but also the forum down  ;D

There's nothing quite like making yourself look an idiot in public, written media  :D
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: TheBoy on 11 January 2019, 18:04:30
Another thought, and something that chrisgixer always grumbled about, the servo in the Omega doesn't give massive assistance, which can give the sensation of "weak" brakes.

Not sure of your age, but many of us of a certain age would be quite used to non servo assisted brakes, so probably notice it less than those have always had servo assistance.


Hmmm....
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Nick W on 11 January 2019, 18:12:37
Another thought, and something that chrisgixer always grumbled about, the servo in the Omega doesn't give massive assistance, which can give the sensation of "weak" brakes.

Not sure of your age, but many of us of a certain age would be quite used to non servo assisted brakes, so probably notice it less than those have always had servo assistance.




Some of us actually prefer non-servo brakes on a light car......



Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Doctor Gollum on 11 January 2019, 18:15:05
Mk 2 Polo anyone? :D
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Doctor Gollum on 11 January 2019, 18:17:30
The Omega needs a lot of pedal movement. If you're used to Fordesque fart-and-it-locks-up shite, it will be an unusual sensation.

I don't think that's it - I spend most of my driving time in old Vauxhalls, 4x4s, vans and trucks!

I wonder if maybe I've got some particularly rubbish pattern pads. Probably a case of me overthinking it and jumping to a silly conclusion instead of finding the most sensible and likely one
Drive a Unimog hard and then complain about your Omega brakes  ;D

When you bled it, did you push the pistons fully home?
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: TheBoy on 11 January 2019, 19:15:54
Another thought, and something that chrisgixer always grumbled about, the servo in the Omega doesn't give massive assistance, which can give the sensation of "weak" brakes.

Not sure of your age, but many of us of a certain age would be quite used to non servo assisted brakes, so probably notice it less than those have always had servo assistance.




Some of us actually prefer non-servo brakes on a light car......
Of all things I have described Omegas as, light has never, ever, ever been one of them.
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: polilara on 12 January 2019, 08:34:39
When I press the pedal smoothly the movement is quite long and I have a feeling of bad brakes. When I quickly release pedal and make another press the movement is much shorter and brakes are much more powerful. like the assistant worked more effectively in the first centimeters of the movement.
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Kevin Wood on 12 January 2019, 08:43:12
The one thing I've noticed from hanging around various car forums for the last 20 years, building a kit car and so on, is that you can never have a setup where the brake pedal feel suits everybody's tastes.  ;)
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Andy H on 12 January 2019, 08:50:00
When I press the pedal smoothly the movement is quite long and I have a feeling of bad brakes. When I quickly release pedal and make another press the movement is much shorter and brakes are much more powerful. like the assistant worked more effectively in the first centimeters of the movement.
new discs, pads and a flush of the brake fluid should fix that
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: Doctor Gollum on 12 January 2019, 11:28:12
When I press the pedal smoothly the movement is quite long and I have a feeling of bad brakes. When I quickly release pedal and make another press the movement is much shorter and brakes are much more powerful. like the assistant worked more effectively in the first centimeters of the movement.
new discs, pads and a flush of the brake fluid should fix that
This. But only if you press the pistons home with the bleed nipples open before you bleed the fluid. Otherwise you retain enough dead fluid to make a noticeable negative difference  ;)
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: sjc on 12 January 2019, 20:09:58
When I press the pedal smoothly the movement is quite long and I have a feeling of bad brakes. When I quickly release pedal and make another press the movement is much shorter and brakes are much more powerful. like the assistant worked more effectively in the first centimeters of the movement.
new discs, pads and a flush of the brake fluid should fix that
This. But only if you press the pistons home with the bleed nipples open before you bleed the fluid. Otherwise you retain enough dead fluid to make a noticeable negative difference  ;)

^wot he said

BTW, if buying GM pads, 9192124 are the crap "Aftermarket Specification", always try to get the OE pads 9195077
Title: Re: Astra H SRi 2.0 Turbo brakes on Omega?
Post by: TheBoy on 13 January 2019, 10:56:01
BTW, if buying GM pads, 9192124 are the crap "Aftermarket Specification", always try to get the OE pads 9195077
The Aftermarket TC pads are the ones I have abused, as that's what was always fitted to the Silver Bullet ;).  TBE tends to have the OE ones fitted.

The only performance difference seems to be the TC ones lack initial bite if the car has been stood several days, a problem the the OE ones don't suffer.

A few years ago, the OE ones created less dust, but that's no longer the case IME.