Upgrading ZR-1 Front Brakes to C5/C6 brakes

[QB93Z]

At today's WAZOO WMD we upgraded Glenn's 1990 ZR-1 front brakes to C5/C6 brakes.

Glenn has been aggressively racing his ZR-1 for 20 years and wanted to upgrade his stopping power for this year's racing season.

The goals of the upgrade were:

Increase the front brake swept area to reduce disk peak temperatures,

Use readily available components so consumable cost during the racing season was reasonable,

Replace the tie rod ends that had been heat damaged and fabricate a heat shield.

Here is the before picture of the driver's side brakes. In the background you can see parts of the brake rotor cooling system that Glenn added to try to cool the brakes.
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03218.jpg


You can see the heat damage the hot rotor has caused to the nearby tie rod and lower spindle boots:
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03237.jpg



Here are the parts that were used. All of the parts are stock, C5/C6 parts except the new adapter brackets and bolts.
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03227.jpg



After removal of the original brakes, the adapter was fit to the spindle. The machined recesses in the adapter face the caliper frame:
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03250.jpg


The adapter came with washers that are used as spacers to align the caliper to the rotor. Some trial and error was required to get the proper spacing:
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03251.jpg


Here the rotor and caliper frame have been installed:
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03258.jpg


More to follow.

[QB93Z]

The rest of the installation follows standard brake rebuild procedures.
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03263.jpg

The existing braided brake lines were uesd. In order to avoid contact with the wheel sensor cable, the cable brackrt had to be offset a little:
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03265.jpg


Install complete:
http://i407.photobucket.com/albums/pp152/QB93Z/2010%20May%20WMD%20for%20C6%20brakes/DSC03268.jpg




Jim

[secondchance]

Terrific! When will he have the car back on the track to report on the improvement?
Seems to be relatively straight forward and a worthwhile modification.:thumbsup:

[DaveK]

Thanks, nice write up :thumbsup: Going to be taking on that job soon. :)

[Scrrem]

Look at this job myself, I'll be curious to hear from Glenn if he notices a vast improvement in braking performance.
Rich

[QB93Z]

:thumbsup:

What is C6? The rotors are C5?
Did you use Loctite 262 RED on the adapter bolts?

I am having a tough time keeping up with the INDEX http://www.zr1.net/forum/showthread.php?t=11619 adding these super picture posts :thumbsup:

Aa far as the difference between C5 and C6 components, I don't know. I believe that the parts Glenn used were compatible with both.

We used blue locktite.

Jim

[XfireZ51]

With the Z06 wheels I put on my 92, now I can think of upgrading to the C6 Z51 (13.5" rotor) or possibly the 6 puck C6 Z brakes. Currently, I have the C5 upgrade with the DRM bias spring.

[-=Jeff=-]

just curious, but whose adapter brackets are those?

[GOLDCYLON]

Looks like Jeffvette's but unsure

[QB93Z]

just curious, but whose adapter brackets are those?

I do not know the manufacturer of the brackets. Glenn got them from someone else who was going to do the conversion and then changed his mind.

Jim

[QB93Z]

Just for general info, and maybe everyone knows this already, but a stock 1990 front wheel will NOT fit over the C5/C6 caliper. I tried it and there is interference with the outer corner of the caliper and the inside of the barrel where the the barrel diameter eases in to the connection with the wheel "spokes".

I should have tried to put one of my 1993 sawblades on after the conversion but we got side tracked and forgot.

Jim

[A1990]

Sources for these brackets would be nice to know.

[-=Jeff=-]

Just for general info, and maybe everyone knows this already, but a stock 1990 front wheel will NOT fit over the C5/C6 caliper. I tried it and there is interference with the outer corner of the caliper and the inside of the barrel where the the barrel diameter eases in to the connection with the wheel "spokes".

I should have tried to put one of my 1993 sawblades on after the conversion but we got side tracked and forgot.

Jim

I have heard they may work with a spacer

[Aurora40]

That's surprising that you need washers with a floating caliper setup. Does the C5 bracket sit a lot closer to the rotor than the stock one?

[RICKYRJ1]

With the Z06 wheels I put on my 92, now I can think of upgrading to the C6 Z51 (13.5" rotor) or possibly the 6 puck C6 Z brakes. Currently, I have the C5 upgrade with the DRM bias spring.

I have this upgrade with Baer 2 pc rotors, love it but upgraded to C6Z06 :thumbsup: Might have the Z51 setup up 4sale soon

[XfireZ51]

I have this upgrade with Baer 2 pc rotors, love it but upgraded to C6Z06 :thumbsup: Might have the Z51 setup up 4sale soon

Can you say more about what the Z06 upgrade requires? Adapters etc?

[RICKYRJ1]

Can you say more about what the Z06 upgrade requires? Adapters etc?

You need a Z06 adapter plate, calipers bolt up nice & easy.I picked up some new Z06 GM rotors to use for now also. I'm running the C6Z06 wheels like you so fitment is not an issue. Will upgrade the rims next year when I can free up some $$$. I'm still trying to figure out the rears without eliminating the parking brake. Time is getting short with BG around the corner.
I bought everything from CF members in the C6 parts 4sale section and have spent about $1200.00 for all brand new GM parts :-D

[XfireZ51]

Rick,

Are you driving ZR out to BG? What adapters did you use and where are they available?

[RICKYRJ1]

Rick,

Are you driving ZR out to BG? What adapters did you use and where are they available?
Yes I will be driving to BG. I got the adapters from a guy On CF C6 section.I have a local guy who can make them or Street Shop out of Alabama might sell them, they may also have a solution for the rear C6Z06 upgrade. :pray I am giving them a call tomorrow.

[POWERBRAKEBOB]

I not only rebuild power brake units, but have been modifying them for more output to the handicapped for 40 years. The valving inside can be modified to increase the booster's power. Ido a lot of Hydroboost conversions, particularly on muscle cars and trucks, and have even installed Hydroboosts on C-4's. I also have Dual Diaphragm boosters for non ZR-1 Vettes. Drilling holes in rotors doe NOT raise the brake pressure. If the rotors are overheating, it usually indicates that the pressure is too low in any vehicle.

[mike100]

I not only rebuild power brake units, but have been modifying them for more output to the handicapped for 40 years. The valving inside can be modified to increase the booster's power. Ido a lot of Hydroboost conversions, particularly on muscle cars and trucks, and have even installed Hydroboosts on C-4's. I also have Dual Diaphragm boosters for non ZR-1 Vettes. Drilling holes in rotors doe NOT raise the brake pressure. If the rotors are overheating, it usually indicates that the pressure is too low in any vehicle.

I had thought about acquiring a dual diaphragm booster for a non-ZR-1 once. The regular PBR booster is completely mismatched on the regular coupe. hydroboost also sounds interesting and would give a lot of cam cover clearance. Please make a new post if you have pics or anything else to share. If I ever get another LT1 coupe, I would really want to do something about the factory power boost.

[ksphar]

Rick,

Are you driving ZR out to BG? What adapters did you use and where are they available?

I will be at the Gathering next week. I carry these brake caliper adapter brackets for C5 calipers, and can bring a set with me if anyone would like to look at them. They are in a polished finish.

Thanks!
Kevin

[Kevin]

I will be at the Gathering next week. I carry these brake caliper adapter brackets for C5 calipers, and can bring a set with me if anyone would like to look at them. They are in a polished finish.

Thanks!
Kevin

would you mind posting a link? i can't seem to find them on your site

[ksphar]

would you mind posting a link? i can't seem to find them on your site

Kevin,

Here is a link to our brackets, part # 500583 (http://www.keenparts.com/pages/detail.php?partnum=500583&PL=469). Let me know if you have any questions about them. We just sold a set to a local customer who was very happy with them.

Thanks!
Kevin

[Kevin]

Kevin,

Here is a link to our brackets, part # 500583 (http://www.keenparts.com/pages/detail.php?partnum=500583&PL=469). Let me know if you have any questions about them. We just sold a set to a local customer who was very happy with them.

Thanks!
Kevin

Thanks Kevin.

[mike100]

Kevin,

Here is a link to our brackets, part # 500583 (http://www.keenparts.com/pages/detail.php?partnum=500583&PL=469). Let me know if you have any questions about them. We just sold a set to a local customer who was very happy with them.

Thanks!
Kevin

I have a set of those- they worked well- machined true and squared up the bracket to the rotor plane nicely. I have a mis-machined bracket set from somebody else that didn't fit at all. Maybe they can be fixed, but I just looked around to find those powder coated gray brackets semi-locally. You have to use the washers in various spots, but it works out well.

Do you guys make those in house?

[ksphar]

I have a set of those- they worked well- machined true and squared up the bracket to the rotor plane nicely. I have a mis-machined bracket set from somebody else that didn't fit at all. Maybe they can be fixed, but I just looked around to find those powder coated gray brackets semi-locally. You have to use the washers in various spots, but it works out well.

Do you guys make those in house?

We do not make them in house. We found a supplier for them and they are a very nice product. We just sold a complete C5 upgrade package with the red Z06 calipers and drilled / slotted rotors to a local guy who said the brackets worked perfect.

Kevin

[Kevin]

what would the complete package run?

[ksphar]

what would the complete package run?

Kevin,

Email me at kevin@keenparts.com, or call me at 800-757-5336, and we can put a package together. With so many options (drilled or plain rotors, braided lines, brake pad type, etc.), I need to know exactly what you want. We should be very competitive with the other retail companies out there. The last package we did, we matched the C5 front with drilled rotors and red calipers out back as well.

Thanks!
Kevin

[Kevin]

are the base C5 calipers the same as the z06 calipers? does anyone know?

[XfireZ51]

]


Yes, just painted red on the C5.

[Kevin]

Kevin,

Email me at kevin@keenparts.com, or call me at 800-757-5336, and we can put a package together. With so many options (drilled or plain rotors, braided lines, brake pad type, etc.), I need to know exactly what you want. We should be very competitive with the other retail companies out there. The last package we did, we matched the C5 front with drilled rotors and red calipers out back as well.

Thanks!
Kevin

Email sent

[Kevin]

]


Yes, just painted red on the C5.

that's good to know, I prefer the black ones :)

[GOLDCYLON]

I have to ask is this mod really worth it? Im running 96CE calipers (J55s really) with Hawk racing pads and Baer 2 piece Eradispeeds already both front and rear. This setup works well. I remember Bob was not all that impressed when he did his large brake upgrade. So for those of you that autocross out there. Im not sold that just the calipers is an improvement without a change out of the Master cylinder and booster to something beefer. Somebody who knows please weigh in here. I have wondered about this for a long time. If these are so rad why are C5 and C6 owners upgrading from stock? Im just asking as everybody seems to be upgrading their rotors as well which I think is equally key as well as the High performance pads. Somebody???? Am I wrong? :cheers:

[lbszr]

I have to ask is this mod really worth it? Im running 96CE calipers (J55s really) with Hawk racing pads and Baer 2 piece Eradispeeds already both front and rear. This setup works well. I remember Bob was not all that impressed when he did his large brake upgrade. So for those of you that autocross out there. Im not sold that just the calipers is an improvement without a change out of the Master cylinder and booster to something beefer. Somebody who knows please weigh in here. I have wondered about this for a long time. If these are so rad why are C5 and C6 owners upgrading from stock? Im just asking as everybody seems to be upgrading their rotors as well which I think is equally key as well as the High performance pads. Somebody???? Am I wrong? :cheers:

I can't give comparisons, since I'm still running the J55's. But mine went through the wringer at a road track by a ttu/st1 road race national champ. He was toe heal shifting from very hard stops, and the the pedal was solid and equal with the gas pedal for the blip, so I don't know how it could be much better. He was braking and driving very hard, the limiting factor was the tires, after just 3 laps the water and oil temp were both approaching red line. The brake feel to me, seems great.

I agree, pads are key, and expensive. I've seen c5's boil their brake fluid out with stock brakes.

Can just the rotor for the two piece eradispeeds be bought?

[XfireZ51]

I have to ask is this mod really worth it? Im running 96CE calipers (J55s really) with Hawk racing pads and Baer 2 piece Eradispeeds already both front and rear. This setup works well. I remember Bob was not all that impressed when he did his large brake upgrade. So for those of you that autocross out there. Im not sold that just the calipers is an improvement without a change out of the Master cylinder and booster to something beefer. Somebody who knows please weigh in here. I have wondered about this for a long time. If these are so rad why are C5 and C6 owners upgrading from stock? Im just asking as everybody seems to be upgrading their rotors as well which I think is equally key as well as the High performance pads. Somebody???? Am I wrong? :cheers:

GC,

The caliper on the C5 is thicker and stiffer. The rotors are also thicker with slightly less (12.8") diameter. Besides, technology marches on which is why someone would upgrade even C6 hardware.

[Scrrem]

I just upgraded to C6 brakes on my 90 and there is without a doubt more contact area with the larger calipers.
Rich

[xlr8nflorida]

I have to ask is this mod really worth it? Im running 96CE calipers (J55s really) with Hawk racing pads and Baer 2 piece Eradispeeds already both front and rear. This setup works well. I remember Bob was not all that impressed when he did his large brake upgrade. So for those of you that autocross out there. Im not sold that just the calipers is an improvement without a change out of the Master cylinder and booster to something beefer. Somebody who knows please weigh in here. I have wondered about this for a long time. If these are so rad why are C5 and C6 owners upgrading from stock? Im just asking as everybody seems to be upgrading their rotors as well which I think is equally key as well as the High performance pads. Somebody???? Am I wrong? :cheers:

I have the Baer 6s 6 piston setup and it rocks.

[Aurora40]

I have to ask is this mod really worth it? Im running 96CE calipers (J55s really) with Hawk racing pads and Baer 2 piece Eradispeeds already both front and rear. This setup works well. I remember Bob was not all that impressed when he did his large brake upgrade. So for those of you that autocross out there. Im not sold that just the calipers is an improvement without a change out of the Master cylinder and booster to something beefer. Somebody who knows please weigh in here. I have wondered about this for a long time. If these are so rad why are C5 and C6 owners upgrading from stock? Im just asking as everybody seems to be upgrading their rotors as well which I think is equally key as well as the High performance pads. Somebody???? Am I wrong? :cheers:

One huge plus of the C5/6 upgrade is the size of the rotor. It is 1.25" wide vs 1.1" wide of the J55 rotor. The caliper is not all that much bigger, so it may not have as much effect on the bias as a 6-piston upgrade does.

But you are right, the J55 brakes are certainly more than enough for most use. I've hot-lapped them at the drag strip and never found them to be lacking with just stock rotors and HPS pads.

As far as why C5/6 owners upgrade, it's because that's what you do. Same reason people with red taillights buy ones with yellow in them. And people with yellow lights buy clears. It doesn't matter that the stock stuff is good enough, it matters that you can spend money on something different and feel like it's better. ;)

I'll also clarify, a few other people have driven my car hard, and they said the brakes felt normal. I should have let more people try them to see for themselves. The pedal felt long to me, but I can barely remember what they felt like stock. I also mentally compared them to the CTS-V more as I had it more. The C4 used to be "normal" for feel and the Caddy felt weird, eventually the Caddy felt "normal" and driving the 'vette felt weird.

[gbrtng]

I can't give comparisons, since I'm still running the J55's. But mine went through the wringer at a road track by a ttu/st1 road race national champ. He was toe heal shifting from very hard stops, and the the pedal was solid and equal with the gas pedal for the blip, so I don't know how it could be much better. He was braking and driving very hard, the limiting factor was the tires, after just 3 laps the water and oil temp were both approaching red line. The brake feel to me, seems great.


I'm smiling to myself wondering what rotors you are using. The stock AC Delco ones would be heat checked within three laps unless you are moving a lot of air to them. Reminds me of days at GingerMan ...

[-=Jeff=-]

Okay so since this is a C5/C6 brake thread, what are the differences with the C6 Z51 and Base C6?

I think the C6 base and C5 are very close if not almost the same (except the lettering)

[XfireZ51]

Okay so since this is a C5/C6 brake thread, what are the differences with the C6 Z51 and Base C6?

I think the C6 base and C5 are very close if not almost the same (except the lettering)

Actually the Z51 is a 13.5" rotor vs 13" .

[lbszr]

I'm smiling to myself wondering what rotors you are using. The stock AC Delco ones would be heat checked within three laps unless you are moving a lot of air to them. Reminds me of days at GingerMan ...

Good old AC Delco. Oh there definetly cheat checked. If they're not heat checked, I'm probably not having fun:cheers: I'm using brake ducts with a backing plate fitted to the back of the rotors and forces the air out the vents. I am curious how long the eradispeeds would hold up on the track.

[-=Jeff=-]

Actually the Z51 is a 13.5" rotor vs 13" .

What about the calipers?

[Blue Flame Restorations]

An old thread, I know BUT.........I am upgrading to a C5 Z06 caliper.

QUESTION IS???????

1) Will I need a spacer if I use an A-Mold 9.5" front wheel?
2) Will I need a spacer if I install a 1990 9.5" front wheel?

Thanks

[VetteMed]

An old thread, I know BUT.........I am upgrading to a C5 Z06 caliper.

QUESTION IS???????

1) Will I need a spacer if I use an A-Mold 9.5" front wheel?
2) Will I need a spacer if I install a 1990 9.5" front wheel?

Thanks

Brett, the a-molds will clear. I am running C5 calipers with stock A-molds, with no clearance issues. no spacer needed.

I am not certain about the 1990 wheels, however. I suspect that they will not clear.

Andrew

[Blue Flame Restorations]

Brett, the a-molds will clear. I am running C5 calipers with stock A-molds, with no clearance issues. no spacer needed.

I am not certain about the 1990 wheels, however. I suspect that they will not clear.

Andrew

Thanks, Andrew

It currently has 90 wheels on it now. I was planning on installing my A-molds until I get 335's for my Dymags.

Brett

[XfireZ51]

Thanks, Andrew

It currently has 90 wheels on it now. I was planning on installing my A-molds until I get 335's for my Dymags.

Brett

I believe the salad shooters will not clear.

[Blue Flame Restorations]

I believe the salad shooters will not clear.

Thanks, Dom. I'm selling them anyway. They were on the car when I picked it up. They're for sale and they're pretty nice!!....anyone?????

[cvette98pacecar]

I do not know the manufacturer of the brackets. Glenn got them from someone else who was going to do the conversion and then changed his mind.

Jim

The bracket has me a little awe struck, This bracket was built for a C4 to C5 upgrade what is the reasoning for the spacers? I also noticed that there were three washer on the bottom of the bracket and one on the top. Is it just poor engineering or will every install differ?

Anyway it looks great.

[Blue Flame Restorations]

The specific bracket I was asking about is the abutment bracket.

[mike100]

I have those same brackets. I do not recall using two washers in any position- I think I used one on the top and maybe none on the bottom - it sat square.

At anyrate, I bought mine from Exotic Muscle in PHX. Keen Parts also sells the same bracket- don't know who makes them, but I can tell you three things:

1) The grey powdercoated ones shown in this thread are good parts, but do tend to locate the caliper more to the outside edge of the rotor than the VB&P abutment brackets.
2) The VB&P ones I had were not machined true- the bracket did not mount in plane with the rotor- I gave them away. CF threads from other people reported the same problem- I would not mess with them if you are in a hurry to get your car back on the road.
3) The factory spare tire will not work with the C5 front brake conversion- I bought a 17" GTO spare. The hub hole on the gto wheel is about 1mm too small- you need to grind off .050 os so to get it to fit. That said, the grey powdercoated brackets sit very outboard and you may have to trim the fins on the calipers a little or use another bracket to clear the spare...there is always the 18" CTS spare as an option (if you can locate one). The other brackets may clear the GTO spare with out extra caliper modification.

http://i29.photobucket.com/albums/c265/mschrameck/Cars/gto_spare_sm_2.jpg

http://i29.photobucket.com/albums/c265/mschrameck/Cars/gto_spare_sm_3.jpg

Oh, and yes, it's A-Mold time for sure- they just clear and tell your tire guy to put the weights on the very edge.
http://i29.photobucket.com/albums/c265/mschrameck/Cars/DSC03668.jpg