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h16 h16 is offline
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brake proportioning options

I'm considering replacing/removing brake proportioning valve. I currently have stock calipers which I recently rebuilt (thanks to Pelican for tech article on rear caliper). It still feels spongy to me, although I can stop pretty effectively & reliably. I did try lot's of bleeding with pressure bleeder, and I did loosen both fittings at proportioning valve (to bleed) when under pressure.

I've read that some have replaced proportioning valve with a mere junction block. Does anyone have experience or recommendations on options such as this?

I'm also about to put bmw 320 calipers up front. I would expect this to change the proportioning requirements. Any known "adjustable" proportioning valves out there that are recommended?
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Old 09-15-2005, 02:11 AM
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it's common to replace the valve with a "T" purchased for about $5 at the local VW shop....
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Old 09-15-2005, 03:29 AM
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If you still have stock brakes, I would not recommend replacing the proportioning valve with a "T". Locking up the rears before the fronts is a good way to get the car to swap ends. There are a few people who have not had difficulties with the T and stock brakes, but I think those are the exception rather than the rule.

If you put calipers with larger pistons up front, you change the front-to-rear bias toward the front. You can then reduce the pressure-limiting effect of the proportioning valve (theoretically the stocker is adjustable; or you can go aftermarket) to move the balance toward the rear, leaving it in more or less the same place where it was.

Some people go to a 'T' when they put the 320 calipers on the front, but the good folks at Grassroots Motorsports magazine (http://www.grassrootsmotorsports.com) found that they still needed a little bit of rear pressure limiting action even with that setup.

Tilton makes an excellent proportioning valve; one which does not introduce any sponginess or springiness into the pedal feel. I don't know who makes the one we sell, but I am confident that it is a quality piece as well. You will have to make brake line adaptors to plumb either one into the system, though! I know someone was selling a complete setup (valve, T, adaptor lines, all together) but I don't remember who it was.

I hope this helps.

--DD
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Old 09-15-2005, 08:04 AM
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I have the 320i setup and I left the stock proportioning valve alone. Everything works great.

Vern
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Old 09-15-2005, 09:12 AM
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