MG ZR: Cams & Maps

[procta]

Steve what size are the brakes on this? Is there an upgrade from the MGZT or similar? That could be a good option.

The MGF 160 brakes are pretty epic but ruddy expensive. The discs are MEGA bucks

the mgf 160 are AP brakes, and use the same stud pattern as the rover metro, They wont fit the posh rover, I could run the AP brakes if I wanted to but that means bigger wheels.

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another thing with the VVC is the ratios of the gear box, I have a none vvc gearbox which helps me ride the power more. Bit like the HDi gears compared to the Dturbo gear box.

[Piggy]

Ahhh fair enough.

It is why I dislike the MGF a lot... You look underneath and its just a cut and shut of old rovers

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Empty CV joints for the front hubs for instance and a 200 subframe bolted on the back but with the unused brackets still in place

[Matt-Rallye]

Ahhh fair enough.

It is why I dislike the MGF a lot... You look underneath and its just a cut and shut of old rovers

This is precisely the reason i like rovers and parts are cheap!

[Piggy]

MGF 160 front brakes are NOT cheap.

Plus cheap is not always better.... As steve found when on circuit with his cheap brakes and tyres!

[procta]

Ahhh fair enough.

It is why I dislike the MGF a lot... You look underneath and its just a cut and shut of old rovers

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Empty CV joints for the front hubs for instance and a 200 subframe bolted on the back but with the unused brackets still in place

the mgf is just 80 % rover metro tbh, only good thing about the mgf is that they make good donors for the rover metros!

[Piggy]

Aye. Quite a PR succes for Rover really.

I wasnt a fan really, then I had a 160 on the ramp at work and started seeing all these bodges. I was quite shocke tbh

[procta]

steve its the front brown sensor on the water elbow, maybe black on yours as its a mems3, that might be corroded to f*ck.

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Aye. Quite a PR succes for Rover really.

I wasnt a fan really, then I had a 160 on the ramp at work and started seeing all these bodges. I was quite shocke tbh

the mgf is a miss match of parts tbh,

[lolsteve]

Steve what size are the brakes on this? Is there an upgrade from the MGZT or similar? That could be a good option.

283mm so about the same as gti6 brakes? Think racing fluid will be a nice upgrade, means I don't have to bleed the brakes everytime I go for a drive. Any recommendations on the fluid or they much a muchness

Aye. Quite a PR succes for Rover really.

I wasnt a fan really, then I had a 160 on the ramp at work and started seeing all these bodges. I was quite shocke tbh

No bodges just recycling at its best

steve its the front brown sensor on the water elbow, maybe black on yours as its a mems3, that might be corroded to f*ck.

I see, does this one not control the temp gauge?

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Who lowered the engine size!

[Piggy]

Haha, love the title change.

Yeah they plenty big enough really. Just need better pads and some decent fluid.

Just get non silicone based 5.1 fluid. Comma is what I have always used, decent price, never let me or any other mates in rallies/track cars down. Costs about £9 a litre I think, probably want 2 litres as it may only take 1 litre, but you wana make sure you have flushed out the old stuff really well.
Its best to open all the bleed screws and let it empty overnight, then run the 2litres through it.

[procta]

Steve what size are the brakes on this? Is there an upgrade from the MGZT or similar? That could be a good option.

283mm so about the same as gti6 brakes? Think racing fluid will be a nice upgrade, means I don't have to bleed the brakes everytime I go for a drive. Any recommendations on the fluid or they much a muchness

Aye. Quite a PR succes for Rover really.

I wasnt a fan really, then I had a 160 on the ramp at work and started seeing all these bodges. I was quite shocke tbh

No bodges just recycling at its best

steve its the front brown sensor on the water elbow, maybe black on yours as its a mems3, that might be corroded to f*ck.

I see, does this one not control the temp gauge?

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Who lowered the engine size!

you have two, one that is under the water elbow controls the temp gauge, the other one that is towards the radiator, is for the ECU, ( that's the one that can make these act the goat)
here is mine, yours will be black, ( BMW sensor)

Also change this black box of tricks too, as this made a difference too!

[lolsteve]

How about this brake fluid? ATE Super R Blue Dot 4 Brake Fluid
http://www.carparts4less.co.uk/cp4l/p///...&0&cc5_179
I was running pagid 5.1 but it seems to boil up quite quick.

Procta whats that black box?

[Piggy]

If you have got Pagid 5.1 fully synthetic fluid in there already, then I would think it VERY unlikely its boiling. Something else is up there steve.

[Toms306]

DOT 5.1 shouldn't be boiling until well over 200c....you cant be creating so much heat in there!

[Piggy]

DOT 5.1 shouldn't be boiling until well over 200c....you cant be creating so much heat in there!

good 5.1 should be closer to 250degrees.

Seriously doubt its that....and if it is, something is creating too much heat...and DOWNGRADING to dot4 isnt going to help!

[Anton]

Personally i agree with Procta... The biggest difference is the gearbox. PG1's are notoriously long, i loved my Rover Coupe VVC and it suited me perfectly. 70 in 2nd and 100mph in 3rd ha. Rowell has got a much shorter 6 speed on.

[Piggy]

The box ratios kind of depend on the track surely?

[procta]

the black box is called a Multi Function Relay Unit, This unit operates the Fuel Pump, the Starter Motor Solenoid, the ECU power and the Oxygen Sensor.

If either of the 1st three malfunction the car won't start, if the Oxygen sensor relay is faulty the engine will not run efficiently on warm up.

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Personally i agree with Procta... The biggest difference is the gearbox. PG1's are notoriously long, i loved my Rover Coupe VVC and it suited me perfectly. 70 in 2nd and 100mph in 3rd ha. Rowell has got a much shorter 6 speed on.

didn't the BRM or the VI have a very short ratioed gearing?

[Poodle]

How come he needs to replace that Procta, i thought the car was running fine?

What happened when your brakes went Steve? Did the pedal go to the floor or did it go hard and ineffective? I assume it was the latter, as a pedal that goes to the floor tends to cause a lot more panic in a situation like that. Reason i ask is that i don't think you boiled the fluid, that 5.1 isn't very old. What pads is she running..?

[welshpug]

That 6 speed unit isnt short.

[lolsteve]

The 160 ratios are meant to be shorter though than normal or something part of the "mg" Ness although probably not as short as a brm lsd box
Using greenstuffs and I was braking very aggressively and late to try and minimise cruising down speed. Can't quite remember as was a lot going on at the time just remember pushing the brake pedal has hard as I could and not stopping. Niall got in it afterwards and was saying that the pedal goes to the floor with no resistance also just before the rally incident the steering wheel was vibrating hard when braking and think it pulled to the right once. Hence why thought of if there's air then the brakes will be intermittent or only getting on side to work.

[Piggy]

Vibrating and pulling to one side doesnt sound like boiling to me.
5.1 fluid is seriously not guna boil with your car/those speeds/that circuit unless you're on fire or all your calipers are binding

[Ruan]

If the pedal goes to the floor, that's gotta be air in the system rather than typical fade where you get gas between the pad and disc.

Don't get me wrong, Greenstuffs are wank, but not that wank!

[Piggy]

Steve, you say you keep having to bleed the system with road only use??

And it was a hard pedal on track but went to the floor once off track???

What did you do to cure it?

[lolsteve]

Vibrating and pulling to one side doesnt sound like boiling to me.
5.1 fluid is seriously not guna boil with your car/those speeds/that circuit unless you're on fire or all your calipers are binding

The pads were smoking when I pulled up after coming off which was a good couple of minutes driving without using the brakes (also made sure to park up with the handbrake off)

If the pedal goes to the floor, that's gotta be air in the system rather than typical fade where you get gas between the pad and disc.

Don't get me wrong, Greenstuffs are wank, but not that wank!

Air coming from boiling the fluid?

Steve, you say you keep having to bleed the system with road only use??

And it was a hard pedal on track but went to the floor once off track???

What did you do to cure it?

I had a garage bleed the system and fill it with 5.1 after my first track event last year when I thought the pedal was a bit spongy. Then I recently bled it again and go a fair bit of air out the system but don't think I got all of it. And now it's back to it was before the last bleeding
It went to the floor on track and wouldn't stop the car, hence the rally stage. Once it cooled down a bit it would stop again.
Want to bleed it again as soon as possible so need to choose between 5.1 or racing fluid (tempted by the racing one as it's blue )

[Matt-Rallye]

Sounds more like your master cylinder is giving up the ghost tbh...

[Piggy]

Racers will use 5.1.

The dot4 you linked to will boil sooner than 5.1.

You sure they put 5.1 in??

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So pedal went to floor now you say on track?...thought you said earlier it went hard on track but wouldnt stop?

[Poodle]

Sounds like you've got a leak or dodgy components somewhere tbh mate, that or the garage did a seriously shit job of bleeding the brakes. I'd be inclined to look into that a bit further, it's fooking dodgy when the mc starts to go.

[Toms306]

I remember having a brake job done on my first car at a garage.

Replace leaking cylinder.

Left the garage being told 'it'll need to bed in'...first junction hit the brakes not much happened, I cut someone up and got beeped. Assuming it'd get better I carried on. Tbf, the pedal did get slightly better after that, but then the brake light came on and it got considerably worse...hmm, checked fluid level, below minimum!

Ended up taking it back, they said they gravity bled it but that obviously wasn't enough, needed to be pressure bled.

So I wouldn't take the garages word for doing a good job lol. Particularly if it was KwikFit who I haven't used since!

[powerandtorque]

The dot4 you linked to will boil sooner than 5.1.

Don't confuse ordinary DOT4 and Super DOT4 (aka Racing DOT4) fluids.

Super DOT4 is typically higher dry and wet boiling point than DOT5.1

Quick example figures (figures in degrees C):

DOT4 - 230 dry and 155 wet
DOT5.1 - 260 dry and 185 wet
Super DOT4 - 300 dry and 195 wet

As you can see, it pays to keep fluid fresh as older fluid that's absorbed moisture has a considerable lower boiling point.

That said, as others have said, you won't have boiled fresh DOT5.1 fluid on track with ordinary pads - the pads will fade long before the fluid boils and it's not like Castle Combe is a particularly hard track on brakes in my experience.

[Piggy]

Yeah fair enough with full racing dot4....but still boiling 5.1...dont think thats the issue