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Uno brake bias valve
DaveFJ - 24/1/05 at 05:35 PM

Just done a search and can't find the relevant thread, can anyone point me in the direction of how to plumb in and do the neccessary alterations to my newly aquired fiat Uno brake bias valve?

cheers


nick205 - 24/1/05 at 06:30 PM

I made a steel bracket to fit the valve to the footwell bulkhead. The bracket has an adjustable bolt which limits the travel of the bias valves plunger (it rises with pressure). The rear brake line from the master cylinder is then routed through the valve into the lower union and out of the top union.

Hopefully the pictures will make this clearer.... Rescued attachment 031219-07.jpg
Rescued attachment 031219-07.jpg


nick205 - 24/1/05 at 06:30 PM

and another.... Rescued attachment 2.JPG
Rescued attachment 2.JPG


Mark Allanson - 24/1/05 at 07:07 PM

variation on the same theme Rescued attachment BrakePedals&Cylinder.JPG
Rescued attachment BrakePedals&Cylinder.JPG


bob - 24/1/05 at 07:18 PM

And again Rescued attachment MK Indy build pics 081.jpg
Rescued attachment MK Indy build pics 081.jpg


craig1410 - 24/1/05 at 10:11 PM

Hi,
I've done something similar as well and would like to add an important point.

For SVA remember to lock up the adjustment bolt. A split pin or lock nut is not considered suitable so you need to either tack weld it or use a roll pin. This is explicitly permitted provided the roll pin is fitted properly.

For what it's worth I fitted my bias valve above the diff against the seat back panel.

Cheers,
Craig.


DaveFJ - 24/1/05 at 10:25 PM

thanks all, as ever a picture paints a thousand words...


bob - 24/1/05 at 10:36 PM

As most end up taking the retest at SVA i went through with no adjuster on my valve,i thought i would set it at the test and throw a weld on it or pin it after.
As luck would have it the brakes were fine with no adjuster (M8 bolt) the examiner and his examiner scratched there heads a bit but after a brief meeting they decided it was ok

for the record i have the regular sierra/granada rear calipers and the uno valve was bolted on with a 13mm gap between the push rod and the top of the holderalso the top of the push rod is cut flat.

hope this helps.

Also just to make things worst,an indy went through SVA at Beverley with rear discs and no reduction valve according to snoopy at MK.


Ben_Copeland - 25/1/05 at 09:41 AM

Have any of you found that when you hit the brakes the bracket holding your adjuster flexs as the valve pushes against it? Had to strengthen mine, tho seeing all the neat ones on here i might redo mine cos it's ugly!


jps - 28/3/19 at 10:37 AM

Ancient thread revival I know - but are the Uno brake bias valves in any way still useable for IVA? Or is there a current alternative? I'm running discs all round - and a single M/c setup so already expect to have problems with rears locking first


Charlie_Zetec - 28/3/19 at 12:04 PM

Last I heard brake bias valves were still permitted for IVA - as long as they were locked/lockable and unable to come loose.

I see no reason why something like THIS wouldn't be acceptable, assuming it was fixed with a roll pin, lock wire etc. - after all, that's what usually holds the balance bar in position on dual M/C pedal box setups....

Lets wait and see if anyone has recently passed IVA with a similar setup, or you could take a punt and call the local IVA centre and ask for their perspective on the issue? Just remember to get a name or ideally something in writing, as I suspect you'll get different answers on different days from different people!


Schrodinger - 28/3/19 at 06:29 PM

I passed the IVA with a twin cylinder bias setup and a sticker from CBS that says something to the effect that adjusting the bias may lead to the car no longer meeting regulations and that was acceptable, try contacting the centre where you are taking your test and ask their view.