In car Brake bias valve 4 port ? and advice on bias valves

1. barwell1992 Frequent Poster Joined: Mar 2011 Rugby Posts: 752 saxo vtr 02, 150bhp yamaha FZ1:)

   #1 16th October 2012, 22:47

   Is there a 4 port bias valve available that keeps the two lines on a separate circuit? or would the only way to do that by running two bias valves (dont fancy that)
   
   i have had nothing but problems with the standard one, and as i have braided lines from MC to calipers already i have plenty of hose to divert the lines in car with a bias valve
   
   also what single line valves would people recommend? head bad things about the comp brake ones ?
   
   cheers
2. user_16747 Banned Joined: Jul 2007 Posts: 4328

   #2 16th October 2012, 23:07

   The only people that do one are ap racing at around the £300 mark
   
   Look at demon tweeks, it's actually a 2 port one. Two lines enter two exit
   
   As for single ones I can supply willwood ones at £55 each deliverd
3. barwell1992 Frequent Poster Joined: Mar 2011 Rugby Posts: 752 saxo vtr 02, 150bhp yamaha FZ1:)

   #3 16th October 2012, 23:13

   cool, might drop you a PM at some point, for unions/bulk head fittings/t-piece ect just have to hope they don't leak ,i can get bias valves through work at trade so might as well get that at work
4. axsaxoman Saxperience Forum Bum Joined: Jan 2003 Scotland Posts: 3380

   #4 17th October 2012, 08:52

   join both rear brakes together and use a single bias valve
   screw type for infinate adjustment or lever type with notches
   
   your problem with std one, presuming its not old and seized wil be caused as much by the fact it is connected to the suspension ,so incorrect damping or spring rate,front and or rear will make it alter as you go over uneven surfaces as the corner weights shift about .
   this is why race cars don,t use them .
   the std one is a load sensing device to allow more braking from rear when car is loaded , it is not a bias valve .
5. yr51ocw Frequent Poster Joined: Oct 2005 Posts: 751

   #5 17th October 2012, 17:02

   Quote:

   Originally Posted by swampy The only people that do one are ap racing at around the £300 mark Look at demon tweeks, it's actually a 2 port one. Two lines enter two exit

   This! last time I checked it was about £250+vat but that was in 2006.
6. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

   #6 17th October 2012, 17:07

   the 4 port split valves are for people who want to retain the abs.
7. barwell1992 Frequent Poster Joined: Mar 2011 Rugby Posts: 752 saxo vtr 02, 150bhp yamaha FZ1:)

   #7 17th October 2012, 22:53

   the thing im bothered about is the opposing split line system, if i block one of the ports on the MC then run a single line to the bias valve then T off to the rear calipers if the rears lines fail wont that take out one of the front brakes and both of the rears ? leaving me wit only one brake ?
   
   should in that case i move one of the front brake lines so both front lines are opposite each other rather than off set ?
   
   or am i getting completely confused ? lol
8. barwell1992 Frequent Poster Joined: Mar 2011 Rugby Posts: 752 saxo vtr 02, 150bhp yamaha FZ1:)

   #8 18th October 2012, 20:00

   bumpety bump any input on the above
9. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

   #9 18th October 2012, 20:30

   the second bit,.
10. barwell1992 Frequent Poster Joined: Mar 2011 Rugby Posts: 752 saxo vtr 02, 150bhp yamaha FZ1:)

    #10 18th October 2012, 20:46

    cool, and i wont lose brake performance by blocking one of the ports, or should i run 2 rear lines from master cylinder then T together
11. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

    #11 18th October 2012, 20:50

    just use a blank
12. 106maxi Infrequent Poster Joined: Apr 2012 North West Posts: 234

    #12 18th October 2012, 20:52

    And use an AP lever type rather than Wilwood screw type.
13. user_16747 Banned Joined: Jul 2007 Posts: 4328

    #13 18th October 2012, 21:11

    Quote:

    Originally Posted by 106maxi And use an AP lever type rather than Wilwood screw type.

    Why??
    Personally having used both the willwood is better as it is easier to fine tune and adjust by small amounts
14. 106maxi Infrequent Poster Joined: Apr 2012 North West Posts: 234

    #14 18th October 2012, 21:51

    I too have used both. The fine (analogue) control is irrelevant.
    The AP is far superior in quality of build. The more control is a hinderance in a race situation as you forget how much you've turned it, if you've turned it and where you are generally in relation to overall bias.
    AP- no question.
15. user_16747 Banned Joined: Jul 2007 Posts: 4328

    #15 18th October 2012, 22:04

    Quote:

    Originally Posted by 106maxi I too have used both. The fine (analogue) control is irrelevant. The AP is far superior in quality of build. The more control is a hinderance in a race situation as you forget how much you've turned it, if you've turned it and where you are generally in relation to overall bias. AP- no question.

    But in the context of most people on this forum they will set the valve as too how much bias they want and then rarely touch it again.
    
    And not every one wants to / can afford to spend out on an ap item, the one my friend has in his mk2 escort does feel nice and solid but. The lever adjustment IMO isn't so nice to use, far prefer the twist type of the willwood.
    
    It's the same with so many things on a car, what one person thinks is the best thenext person will hate
16. barwell1992 Frequent Poster Joined: Mar 2011 Rugby Posts: 752 saxo vtr 02, 150bhp yamaha FZ1:)

    #16 18th October 2012, 22:15

    with the notch type can you fully close and fully open the valve, or is it within a set range?