ZR-1 Net Registry Forums  

Go Back   ZR-1 Net Registry Forums > C4 ZR-1 > C4 ZR-1 Technical Postings

Reply
 
Thread Tools Display Modes
Old 08-21-2014   #11
USAZR1
 
USAZR1's Avatar
 
Join Date: Oct 2013
Location: Wichita Falls,Tx
Posts: 594
Default Re: Guys with Killer Brakes, what about Rears & Bias????

Quote:
Originally Posted by alnukem View Post
I bought a car & there was a line with a description that said

"C5 Z06 Wildwood Front Brakes w/Guido Movit Master Cylinder Bias Spring"

what/who is Guido movit?
Guido Frensemeyer,owner of Movit-DE
http://www.movitbrakes.com/en/produkte/
USAZR1 is offline   Reply With Quote
Old 08-21-2014   #12
WVZR-1
 
Join Date: Oct 2004
Posts: 1,884
Default Re: Guys with Killer Brakes, what about Rears & Bias????

Quote:
Originally Posted by batchman View Post
The benefit of an F-body master is the 1" piston (vs 7/8" factory all c4). The thing that has stopped me from doing this is just as you mention, rear bias. My car suffers from understeer under braking and I'd rather continue with soft brakes than make that worse.

I have been unable to take the time to figure out how to put in the bias spring to see if helps or hurts.

Of course it took me until this year to realize I'd upgraded the front pads but not the backs - I'll be trying that update as soon as I figure out how to bed new pad types on a non-street car...

Later,
- Jeff
In '92 there were some changes made. The master has a larger bore 23.7mm vs 22.2mm for earlier. The pedal ratio also changed from 3.5 to 4.0 so you could do the math and see if competitively the change to the later master or 4.0 ratio would help in your particular case. The stroke in the rear of the master also changed but I'm not familiar with the effect that that might have.

Now the booster changed as well in '92 along with the push rod so I don't know what might be required to accomplish the pedal ratio improvement. I know that you would need the '92 pedal and the support bolted to the firewall that the pedals swing on. The booster push rod is different also and I don't know that it could be used with the earlier booster.

A 4.0 ratio and the 1" F-body master?

Last edited by WVZR-1; 08-21-2014 at 10:45 AM.
WVZR-1 is offline   Reply With Quote
Old 08-21-2014   #13
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,685
Default Re: Guys with Killer Brakes, what about Rears & Bias????

Quote:
Originally Posted by WVZR-1 View Post
In '92 there were some changes made. The master has a larger bore 23.7mm vs 22.2mm for earlier. The pedal ratio also changed from 3.5 to 4.0 so you could do the math and see if competitively the change to the later master or 4.0 ratio would help in your particular case. The stroke in the rear of the master also changed but I'm not familiar with the effect that that might have.

Now the booster changed as well in '92 along with the push rod so I don't know what might be required to accomplish the pedal ratio improvement. I know that you would need the '92 pedal and the support bolted to the firewall that the pedals swing on. The booster push rod is different also and I don't know that it could be used with the earlier booster.

A 4.0 ratio and the 1" F-body master?
Dave,

That's very interesting. This would appear to explain why I have not found a need to change my master while having installed the Z06 brakes front and rear.
XfireZ51 is offline   Reply With Quote
Old 08-21-2014   #14
alnukem
 
Join Date: Jan 2010
Location: Freedom, PA
Posts: 275
Default Re: Guys with Killer Brakes, what about Rears & Bias????

Quote:
Originally Posted by USAZR1 View Post
Guido Frensemeyer,owner of Movit-DE
http://www.movitbrakes.com/en/produkte/
Thanks for the Translation....looks like good stuff!
alnukem is offline   Reply With Quote
Old 08-21-2014   #15
edram454
 
edram454's Avatar
 
Join Date: Nov 2013
Location: ..
Posts: 693
Default Re: Guys with Killer Brakes, what about Rears & Bias????

My car came with the grand sport brakes and a brake bias spring. Previous owner put hawk track pads on this car and it stops on a dime with no fade. I get lots of dust and squeals but it does stop very good.

ed ramos #3028
edram454 is offline   Reply With Quote
Old 08-22-2014   #16
batchman
 
Join Date: Jun 2009
Location: I live at Devens, one run at a time
Posts: 454
Default Re: Guys with Killer Brakes, what about Rears & Bias????

Quote:
Originally Posted by FU View Post
The bias spring will calm down the understeer when braking.
Quote:
Originally Posted by WVZR-1 View Post
In '92 there were some changes made.
Cool news, thanks to you both. In my racing class brakes and master are open, and update/backdate is up for grabs so any C4 part is legal.

If I'm lucky the bias spring with more aggressive pads will give me enough rear brake to add a bias adjuster, which really is a rear brake limiter. My problem with the understeer comes from not enough rear brake. If that works then I could perhaps get the higher ratio pedal and/or bigger piston master, but I thought there was something funny about the brake warning light on the later (1 reservoir, right?) master.

I sense a mix/match attempt coming this off-season .

Thanks again,
- Jeff
batchman is offline   Reply With Quote
Old 08-22-2014   #17
WVZR-1
 
Join Date: Oct 2004
Posts: 1,884
Default Re: Guys with Killer Brakes, what about Rears & Bias????

I'd be inclined to try the 4:1 pedal and pedal support and see if I could maybe construct the push-rod to booster so I could keep everything I had. The master cylinder bore change was 1/16" or thereabouts and if the 4:1 showed promise then consider the change to the later master. There's ASR to contend with so it would require substantial thought maybe. Then again maybe not.

I was with a friend at Carlisle who was shopping pretty hard for one of his customers cars and I looked harder than I normally do to see what was laying around and I saw nothing. The problem I anticipated having even if I saw one that was supposed to be later I had nothing to measure and compare to.

I'd think I'd try a buy from one of the salvage guys and request the support and pedal from a known '92+ and see if the booster push rod could be included with the sale.

Demps said he was parting a '91 and he thought he had them so he could take dimensions from his to compare to what you need/want.
WVZR-1 is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 01:26 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright ZR-1 Net Registry 2025