Race Prep Miata race-only chat.
Sponsored by:
Sponsored by:

Prop Valve on Front Brakes?

Thread Tools
 
Search this Thread
 
Old 07-12-2022, 11:44 AM
  #1  
Newb
Thread Starter
 
Wink's Avatar
 
Join Date: May 2014
Posts: 23
Total Cats: 16
Default Prop Valve on Front Brakes?

We've run the Wilwood dual master on the car for years with NB brakes/ST43s and been extremely happy with pedal feel/performance

This year, we moved to the 11'' box mount set up with Dynalites. Race event one we boiled the fluid and got brake fade when pushing really hard. Race two, light pedal pressure directive and no issues, through pad wear was more than expected.

Event two, we increased front spring rate (for a different reason) and found we could barely go to the pedal at all, without locking the front. Pedal feed back has been very vague as well.

Should I be trying to solve this problem with pad selection, or am I on the right track dialing out pressure from the master to the front brakes?

Track only car/ 2,150 weight/ aero/ RS4's
Wink is offline  
Old 07-12-2022, 12:05 PM
  #2  
Junior Member
 
cabowabo's Avatar
 
Join Date: May 2014
Location: Bama
Posts: 462
Total Cats: 118
Default

I'm assuming the dual master doesn't delete the stock prop valve, in which case you'd actually want something like the wilwood adjustable prop valve for the rear lines. If you don't have stock prop valve then just ignore all this. Instead of cutting pressure to the fronts you just need to move the "knee' further out on the rears. If OEM prop valve is still in there then at a certain MC pressure it starts cutting pressure to the rears and the wilwood adjustable prop valve allows you to move that around. I'm installing one now and in a similar situation (2351lbs with me in it, ~175whp, air dam/wing, 1100f/600r spring, 225 skreets RT660 or V730). I was already locking fronts well before rears on OEM NA8 setup and now with BX11 (Gloc R12f/R10r) it hasn't gotten any better. Can't comment on pedal pressure as I just deleted my booster with the honed kit b/c I like the considerable pressure of manual brakes, BUT everytime I've driven an enduro miata with decently aggresive brakes (DTC60) on RS4's I've felt like I could barely touch the pedal with my big toe without getting lockup.

Anyways, my guess is you need wilwood prop valve on REAR lines, but I'm not sure how dual master differs from OEM regarding prop valve.

Here's some info on prop valve near end of page
https://supermiata.com/supermiata-brake-faq.aspx

Last edited by cabowabo; 07-12-2022 at 12:15 PM.
cabowabo is offline  
Old 07-14-2022, 11:56 AM
  #3  
Senior Member
iTrader: (1)
 
thebeerbaron's Avatar
 
Join Date: Dec 2007
Location: San Jose
Posts: 658
Total Cats: 340
Default

I think you've got problems other than proportioning here.

Fade and boiling fluid make me question bleeding procedures, pad choice, and the age/quality of the fluid. Is that sorted out now?

Do you have a proportioning valve for the rear?

Definitely, absolutely read the SuperMiata page linked above, many times.
thebeerbaron is offline  
Old 07-14-2022, 12:24 PM
  #4  
Senior Member
iTrader: (2)
 
Alejo_NIN's Avatar
 
Join Date: Jan 2007
Posts: 583
Total Cats: 17
Default

Originally Posted by Wink
We've run the Wilwood dual master on the car for years with NB brakes/ST43s and been extremely happy with pedal feel/performance

This year, we moved to the 11'' box mount set up with Dynalites. Race event one we boiled the fluid and got brake fade when pushing really hard. Race two, light pedal pressure directive and no issues, through pad wear was more than expected.

Event two, we increased front spring rate (for a different reason) and found we could barely go to the pedal at all, without locking the front. Pedal feed back has been very vague as well.

Should I be trying to solve this problem with pad selection, or am I on the right track dialing out pressure from the master to the front brakes?

Track only car/ 2,150 weight/ aero/ RS4's
i'm also on dual wilwoods...
do you mind showing a pic and the specs of the rear/front masters?

thanks!
Alejo_NIN is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Kboi12
Suspension, Brakes, Drivetrain
56
04-15-2024 04:12 PM
schmoo
Suspension, Brakes, Drivetrain
5
03-23-2018 01:06 AM
lassi
Suspension, Brakes, Drivetrain
22
12-09-2015 04:17 PM
gtred
Race Prep
33
05-11-2012 10:21 AM
hustler
Suspension, Brakes, Drivetrain
54
10-05-2010 01:14 PM



Quick Reply: Prop Valve on Front Brakes?



All times are GMT -4. The time now is 05:29 PM.