Due to its floating rear a 4th gen fbody axle moves in and out also causing the rotor to do the same. The rotor moves less than .5 mm, is that enough to cause pad knocking on a fixed caliper? Lets say a brembo caliper from the rear of a ctsv (2nd gen).

 

From the little research that I have done online, it is enough to cause pad knock back. I'm also interested in finding a way to get some rear cts-v calipers to match the front.

 

The track rats on frrax say yes, but would you ever experience it on the street? Not sure...never took the time or spent the money to find out.

 

If you have an aftermarket rear axle this will not be a problem as they are retained at the wheel end of the axle (no c-clips). So a Moser/Strange 12B; S60, and M9 will not have the in/out motion of the factory axle.

 

That is some good new, maybe this will motivate me more to save up and upgrade my rear differential.

 

It's called pad knock back, and yes, it will occur on both brake types. Baer, Wilwood, and a few others have developed sliders for the calipers to prevent this from happening, but I haven't heard any results yet. The simple solution is a good safety precaution that my friend and instructor told me. It's always a good idea to tap the brakes before entering a braking zone. This will let you know in advance if you have brakes, and it also draws the caliper back into position so you don't have a delay in brake response - albeit minimal.

- Kevin

 

Reference for rotor/caliper specs:
http://www.lukeskaff.com/?page_id=333

10 Bolt SS Brembo rear disk conversion plates?
http://www.flynbye.com/catalog/i238.html

Other goodies
http://www.flynbye.com/catalog/c3_p1.html

Wilwood rears with a 13" rotor.
http://www.wilwood.com/BrakeKits/Bra...sc Brake Rear.

 

I just had a lenghty conversation with a brake tech/designer at Wilwood.

My goal was to get answers regarding 4th gen. rear big brake upgrade, specifically calipers and to see if I could do it as cost effective as https://ls1tech.com/forums/suspension-brakes/1130984-cts-v-brake-install-w-pics.html]WesmanW02. I called them regarding the fbody rear kit being a floating rotor and thier large (fixed) brake upgrade kit. This chumpy to be specific. Yeah, I'm bringing back "Chumpy." Mind you the rotor is 2" smaller in diameter over the ctsv upgrade but the talking point here is floating vs fixed caliper.

Key points:

Q. The obvious, is the caliper a fixed caliper?
A. Yes

Q. Will it have an effect on a 4th generation fbody due to the factory axle being floating (able to move slightly in and out)?
A. If the axle is to factory spec it will not under normal driving conditions. He explained you may feel a bit of "piston knock" if you take a hard corner while braking, even then the only thing you may feel is the pedal get soft. He explained you probably already feel this with a floating caliper, however may not even notice.

I had a concern that never got answered, to no fault of his. We started talking about agressive driving and rambling on about outcomes. I digress, what if I were taking a corner very aggressively, enough to cause the rotor to press into a seated pad at this point not using the brakes, then having to use the brakes, would it cause damage to the caliper? All I can think is that those 5 little heg bolts that hold the caliper together give...I'm probably overthinking thngs.

In short, we spoke in depth about quit a few things. What I brought away was I think the rear can be accomplished with a fixed caliper, considering it is spaced correctly. I also took away what most of the LS1techees already have read 1 billion times, street setup should be fine. As I get older in age I am less of a risk taker. I am a guy that went from doing 150mph runs, canyon carving at 9000' every weekend, to blowing the dust off the car on the weekends. After a little more research I am going to press the "buy" button. I am just not sold on the idea of c-clip wear and that I have .5mm of play in the rear. I guess I just have to keep my fingers crossed and head back to the whiteboard if it doesn't work. There are so many articles on this site and others, it just seems that so few people are ready to be the first to try, 'cept of course the trackees. When are they ever going to chime in? I have yet to find an article that says "Don't do this, you will die, your car will burst into flames and your childrens, grandkids will be born with one ********."

 

If I knew that the rears are direct bolt on I'd do it in a heart beat.

 

Ctsv rears I mean

 

Please keep us updated on how this project goes, I'm very interested.

 

If I could find brake rotor offsets and caliper dimensions I would be set.

 

Have you checked out kore3's website? They have a few PDFs on caliper and rotor dimensions.

 

Great info there, however nothing on CTSV rear rotors.