Improving brake pedal feel
Thread Starter
Burning Brakes
Joined: May 2002
Posts: 831
Likes: 0
From: Albuquerque NM
Improving brake pedal feel
Looking to improve the feel of the brakes on my vette. I just installed a Wilwood 12" rotor/4 piston fixed caliper system on my GN with hydroboost, kit included braided hoses although I'm still using stock rear lines/rear drums. The pedal feel and general braking feels so much better on the GN than the vette. I'm going to order some stainless braided lines for the vette, but will this make a large difference? Vettes pedal feels rather spongy and its not from needing bled. Doesn't seem that the stock rubber lines would be all that bad with 60k miles on them
Pro
Joined: May 2012
Posts: 666
Likes: 30
From: Milwaukee WI
I just bleed my brakes for the season paying specific attention to this as I switched fluid to something that is suposedly less compressable. I just have stock calipers and lines with 38k on them on an 03 with carbotech pads, xp10/xp8. I can say there is still some slop at the top but the pedal does seem to get really hard really fast once you are through the slop at the top of the pedal with the prospeed 683.
I know fluid can create different levels of compresability brand to brand. That is why i spent the money on the prospeed fluid. I don't know that it is magic but there is something to it.
Might be worth it to try changing fluid brands.
I know fluid can create different levels of compresability brand to brand. That is why i spent the money on the prospeed fluid. I don't know that it is magic but there is something to it.
Might be worth it to try changing fluid brands.
Thread Starter
Burning Brakes
Joined: May 2002
Posts: 831
Likes: 0
From: Albuquerque NM
Hm, didn't know about the fluid deal 
I just bled them after my last hpde, but just used no name dot4. I'm planning to get the new lines, so may as well flush the whole thing out with good fluid if it makes a difference.
I just bled them after my last hpde, but just used no name dot4. I'm planning to get the new lines, so may as well flush the whole thing out with good fluid if it makes a difference.
Pro
Joined: May 2012
Posts: 666
Likes: 30
From: Milwaukee WI
If you are getting new lines anyways. I would try a new brand. The prospeed is about as expensive of fluid as i have seen at $25/500ml (outside srf which has terrible compressability) but it is without any doubt less compressable then ate super blue is. I have never tried any other legit fluid, might be worth it to start cheaper than this if you care. I only go through about 1-1.5l a year, so not to big of a deal for me. I wanted something clear also so i could see how dirty the clutch fluid was getting. This is pretty darn clear brake fluid.
i just googled brake fluid compressability and this was one of the first things that came up. http://www.w124performance.com/docs/...essibility.pdf
i just googled brake fluid compressability and this was one of the first things that came up. http://www.w124performance.com/docs/...essibility.pdf
Last edited by Socko; Apr 22, 2014 at 04:50 PM.
Safety Car
Joined: Jul 2001
Posts: 4,871
Likes: 15
From: Detroit's West Side MI
There is no tangible compressibility difference between fluids that are "dry", meaning no water absorbtion. There will be a difference between new and old fluid as the new fluid will be dry. The moisture absorbed by old fluid is what comperesses, not the fluid itself. Replace ALL of the fluid in your system for better pedal feel.
The graph above shows a difference of 0.0015% volume (3.0E-3 minus 1.5E-3)between the SRF and Brembo / AP fluid at 200 degrees C. You can not feel that.
1 liter of fluid would compress to 0.9985 L.
The graph above shows a difference of 0.0015% volume (3.0E-3 minus 1.5E-3)between the SRF and Brembo / AP fluid at 200 degrees C. You can not feel that.
1 liter of fluid would compress to 0.9985 L.
Last edited by ScaryFast; Apr 22, 2014 at 05:17 PM.
