Molotovman

iTrader: (49)

Hey Guys,

I'm in the slow process of putting my car together for autocross and eventually(Hopefully) some track time. I plan on doing the brakes this season, and have everything except for rotors- for which I'm going to just pick up some blanks.

The car is an 89' GTUs and I've already got Hawk HP + pads for all four corners. From talking to other people I've been told the rears will have the tendency to lock up quite frequently and that I should run OEM pads in the back to prevent it.

I can't return the pads and I got a tip the Other day to use a 90-93 Miata Brake proportioning valve. I was told it is a direct swap and that it will apply less pressure to the rear and will help against the lockup.

I've looked on FlyinMiata and found this page with a graph showing braking force.
http://www.flyinmiata.com/tech/stock_bpv.php

Does anyone have a similar graph for stock 2nd Gen Proportioning valves or know the specs?

I'm planning on picking one up the next time I hit the Salvage yard and trying it out when I do the brakes. Do any of you guys have experience with this? This would be much cheaper than getting a brake bias adjuster.

jrx13

iTrader: (3)

I just did this mod instead, I think about $100 in parts, but adjustable in case you change brake compounds.

https://www.rx7club.com/race-car-tech-103/brake-proportioning-valve-931953/

Gian

iTrader: (3)

If I was you, I would see if they will let you exchange the pads for more front pads. Sometimes they will do that even if they will not give you cash back.

Or save them till you have the cash for the proportioning valve.

You can also cut some of the pad off the backing plate to make the working surface smaller.

Molotovman

iTrader: (49)

I saw that and that's what I was originally planning on doing. I'm remodeling my kitchen at my house now so I'm trying to keep the car spending down to a minimum.

@Gian- I got them as a Gift, I don't know where they were purchased.

j9fd3s

iTrader: (3)

specs are in the FSM... at least that's where the miata info is from

Molotovman

iTrader: (49)

Thanks Man! I should've checked that out first.


Here is the FC Specs from the 88' FSM


The Miata 90-93 BPV spec is here:

Year1990-93
A- 427
B- 995
B'- 597
Back to the original question now, Is there anyone running this?