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Caution Fg Brake Upgrade

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Mate

I would ring PBR and ask for there Quality section and talk about your upgrade they supply the master cylinders it could be split in the master cylinder. the ratio of pressure to the frt v rear brakes

gassa

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Has anyone had any further advances on this topic of brake vibrations with 6 pot Brembo's?

I've had my 6 pot / 2 pot setup on the ute for ~10k km now and am experiencing the dreaded vibration. The most common is a slight vibration (more noise than actually felt) at slow speeds (eg. car parks) while turning right, and seems to be coming from the RH front wheel. But I have also had a more major vibration at higher speeds (I.e. 60 - 80km/h) while pulling up for traffic lights and in a straight line.

Has anyone with an FPV had their dealer find a fix?

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Zap, you said the dealer replaced the upper control arm bushes, however that was not the final fix. Have you had any further experience, did you get the sqeak fixed?

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The issue is a resonance within the 6 pot brembo calliper that gives a horrible shuddering noise/feeling through the front end. The current fix is a spacer/washer, about 100mm wide and 5 mm thick fitted to each of the upper control arm mounting points.

This washer is installed at FPV, is engineered by prodrive, and has nothing to do with Ford.

Unfortunately, this is not a permanent fix. The washer degrades over time (8000km or so), eventually wearing to the point wear the washers themselves cause a horrible noise through the front end.

The washers themselves are (relatively) easily replaced, service depts should be able to sort this out.

Happily the permanent fix has now come to fruition - unique upper control arms for 6 pot cars. The first of these are being prioritised on a case by case basis to the customers who have basically complained the loudest. My advice would be to contact FPV customer service (the number elludes me - sorry) calling ford will lead you down a longer garden path - best to call FPV from the start.

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Bunna, thanks for your response, much appreciated.

However could you advise more precisely where this 100mm dia. washer goes? You say it's longevity is rather short, I assume it's not made of steel but from a poly material, perhaps it slips in between the arm and the brackets which bolt to the inner guard, I assume to effectively stiffen the apper bushes?

post-24844-126334032294_thumb.jpg

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What has me thinking the most is why in the first place????

If you have a brake shudder on a new car, you work your way out from, balance & alighnment, then rotor. then bushes etc.?

Like I am not sure and no expert, but I had 6 pot's on my bike, and I ended up with a front brake shudder after about 12,000k's. It ended up being the pad pins wearing. And these are floaters. It was ridden hard, and did at least twenty laps of track days a month. So abused, but pampered after.

I might be wrong but a brake shouldn't shudder in the first place. And if it's naturally going to do it, then no matter what you put in or make bigger it will still only be a bandaid if it's not a simple fix.

Has anyone had their rotors ground ?

Does this happen with anyone with aftermarket rotors? and or pads?

Brembo make great bocks but thier rotors are ordinary. Would be interestinig to know.

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The spacer msut be fitted to the forward side of the aft (rear) mounting point.

So assuming this is a photo of the right hand side (which it isn't)

post-9507-126336123093_thumb.jpg

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Any bushes or spacers you place between the upper arm brackets and the inner guard will ultimately affect the wheel alignment specs of the vehicle, for its at this point that changes are usually made (Barring the use of screw-type camber/castor adjusters) This is getting more interesting all the time..

Mal K

PS Are you able to purchase these new upgraded 6spot upper arms?

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Installing this spacer will not affect wheel alignment (and by that you mean camber/castor - toe is adjustable from the tie rod ends) by your own definition - this spacer is not installed between the upper suspension mounts and the chassis. See the pic below - the critical contribution to castor comes from the position of the upper arms to the chassis (black arrow), and the FPV washer is applied with the upper arm bush on the other side (white arrow).

post-9507-126337421729_thumb.jpg

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Thanks again Bunna for your explanation, I can see now the washer idea is/was a patch job.

The new "FPV unique" replacement upper arm... It will be interesting to have a look at one, however I can only assume the bush end will be different to accomodate a different size or style of bush, any other change will alter the geometry.

I see SuperPro have a replacement upper inner control arm bush set for the FG (part no. SPF3226F) which possibly may be worth a try.

XR09 makes a valid point re. different pad / rotor combos, however I would assume that Prodrive would have looked at that rather than casting a new arm(s).

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kewl

I have already replaced those bushes with superpro. And luckily made up spacers for either end of those bushes. We saw that it was weak when we tested the suspension. And the bush is larger than what it rests on. So we made them as big as the bush. Mine were shagged at 15,000 with std brakes.

I have been sitting on a pair of 6/4's waiting to put them on, but was hoping a fix would come up first. Before I found out I was one of the lucky ones with the dreaded Vibration.

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Stopped at the local dealer while out today. Both 6 pot FPV's in the showroom had the washers as discussed.

Spoke to spare parts, nothing mentioned in the parts catalogue at all. Incidentally, you can't buy the upper control arm bushes seperately, you can only buy a complete upper arm assy.

She went and spoke to the service guys and was told that they had only ever installed the washers to 2 offending vehicles, and that only the workshop can order the parts via the FPV rep who has to inspect the offending vehicle first.

The SuperPro bush set is looking good I think.

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The super pro set is the go. It really puts more feeling into the wheel.

I put normal washers either side as big as the bush. If you look at where it sits there are a lot of sharp edges. Quite a big gap there as well to the weak bracket.

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The super pro set is the go. It really puts more feeling into the wheel.

Did you only fit the SuperPro upper bushes, or have you fitted the lower ones too?

Have you noticed any additional NVH caused by the stiffer bushes, as well as the increased feel?

And yes, the upper brackets fitted to the body do look rather weak.

Edited by FGXR6TUTE

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Yes I replaced the upper and lower and radial. As many as super pro had out at the time.

We had most of the front in bits and a few of the OEM's were already shagged or showing signs of wear @15,000. So while it was out and easy.

Yes there is increased NVH. Not a huge difference but yes. Bumps and ruts are no louder than STD. I would say it increased the tire roar a bit. I am running Tein coilovers as well. So they help out big time. Quite impressive for a Jap damper.

But all that will depend on what you set your ride hight at. And spring rate. I keep mine at 35cm and it's really good on the road. If I go below that it gets to firm and will not perform to it's best on our wonderful roads. It can get quite snappy at the rear if I go to stiff, but I have been trying to get more steering out of it.

Wish I could post a pic but I keep getting a 406 error code.

When the upper control arm bushes came I took them and the retaining bolt to a hardware and found the washers I needed there. I think about 30c each. Mine are about 2mm shotr of the circumference of the bush. And about 2mm wide. I have one on either side of the bush. So 8 all up for the front upper control arms.

The mounts for these bushes are not great and there are a lot of sharp edges in there. And quite a gap from the bush to the bracket That was the reason I fitted the washers in the first place.

I didnt have my brakes on then.

Somthing about somthin doing it right the first time.

Edited by XR09

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I installed the SuperPro upper bushes Thursday night as the vibration problem seemed to get worse and more common in the hotter weather. The OE bushes had been doing a fair bit of back and forth movement as witnessed by the shiny marks on the inside edges of the brackets.

So far a touch more vibration noticed on coarse roads, steering feels a little more direct particularly just off centre, and no vibration while braking.

The OE bushes can be pressed out of the arm, and in fact are a rubber bush with alloy centre sleeve moulded in a plastic outer sleeve, yes plastic.

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FG,

Some good points raised. Got me thinking.

IMO, the plastic outer is not so bad considering it is "housed" in it's respective harder bore and the bore is what provides the structural integrity. The rubber could bear directly against the bore (as BF's do, and most poly bushes do) and there would be no difference. Besides, the rubber has far more give/plasticity (or slop) than plastic. Probably there to just make them easier to install. Now plastic on the inner would concern me. And if the bush has voids in it.....well hmmmmmmmm.

I am thinking that the vibe is caused by the bush hunting/pulsing axially as it really has no firm control over the upright as the brakes are applied. The discs would then experience small changes speed causing the vibe. NO road or disc/pad combination is billiard table smooth. Poly bushes have much more control and probably why the vibe has disappeared??????

These cars can generate >0.5g on cornering, I don't see how they couldn't easily exceed it with some Brembo's and good rubber. The bush in this case is actually in a far worse position as it only has the diagonal (partial) faces of the bush to control axial movement, not the full length and diameter as in-plane cornering loads would impose. And radial voids if they have them (Pat?) are hopeless at constraining fore and aft movement.

FPV fitting the washers and not at least compressing the rubber to increase it's effective durometer will ultimately fail to solve this issue. They SHOULD know better. They should just bight the bullet like you have and fit different and more applicable bush material that can take the increased loads. A bit of included graphite would also give them some lubricity as an added safeguard.

Rubber is cheap, easy to use and quiet. These cars can be damn quick. I think the killer (or main differnce) to a normal T brake combo is the extra force and rate of force that the Brembo's generate on the unsupported upper bushes.

Edited by Smoke them tyres

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And yes, the upper brackets fitted to the body do look rather weak.

Depends what they are made out of. The FG ones look "lighter" than BA/F's, but I think the metal strength/spec has been upgraded. I took a bit of a guess at what that is, did a few calcs and figure they have about a 150% safety/tear margin. That from my knowledge is about the usual safety margin a manufacturer would apply.

Could be wrong though..... :getlost:

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My FG Super Pursuit started this creaking noise the last few weeks even though the packing shims were fitted as per Bunna's post, Ford have a new control arm to rectify this problem, a pair have been ordered for my car but will not be available until around the end of the month.

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I upgraded my fronts to Brembo 6 pots and rears to bigger PBRs about 6000km ago.

I've got this exact issue with my front left brake. It never does it with the right. :crybaby:

Has anyone who's had arms replaced experienced the vibration again?

I can get a set of arms easily, but don't wanna get them unless it definitely fixes the problem... :dontknow:

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Hey bud, just change the upper control are bushes to super pro like I did . Fixed the problem straight away and hasnt come back even after 40K.

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