88 C4 rotors- how do i know if my brakeset is.... heavy duty??

[jpastaman9]

i am getting ready to upgrade my rotors and wheelsets- and they are telling me they cant tell whether my brakes are heavy duty or not from the vin number- Can i find out what type of rotors i have, short of removing the wheels??

any suggestions??

thanks joe.

88 C4

 

[Ken]

These are the specs for the 1987 model year ...

[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]BRAKES, SERVICE:[/font]​

[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Description: [/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Aluminum caliper with nodular iron reaction bracket; pad reaction through bracket[/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Brake type front:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Disc with sliding head caliper, Low drag [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Brake type rear:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Disc with sliding head caliper, Low drag [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Self-adjusting:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Standard [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Special valving type:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Proportioning, integral with master cylinder [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Power brake:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Standard [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Booster type:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Integral; lightweight with tru-bolt reaction system [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Vacuum source:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Inline (intake manifold) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Anti-lock device type:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Electronic 4-wheel, 3-channel (standard) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Effective area:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 27.0 sq in (front), 18.3 sq in (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Gross lining area:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 27.0 sq in (front), 18.3 sq in (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Swept area:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 96.4 sq in (front), 87.5 sq in (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rotor outer working area:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 11.5" (front), 11.5" (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rotor inner working area:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 8.42" (front), 8.75" (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rotor thickness:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 0.8" (front), 0.8" (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rotor material and type:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Vented; gray cast iron (front), damped iron (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Wheel cylinder bore:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 2.1" (front), 1.6" (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Master cylinder bore:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 0.862" [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Master cylinder stroke:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 0.49" [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Pedal arc ratio:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 3.5:1 [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Line pressure at 100 lbs pedal load:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 1250 psi (front), 800 psi (rear) [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Lining clearance:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Self-adjusting [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Front brake lining bonding:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Integral molded [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Front brake lining manufacturer:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Japan Brake Industries [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Front brake lining code:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] CP26 [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Front brake lining material:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Semi-metallic [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Front brake lining size primary:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 5.2" x 1.52" x 0.34" [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Front brake lining size secondary:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 4.4" x 1.56" x 0.34" [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Front brake shoe thickness:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 0.22" backing plate [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rear brake lining bonding:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Integral molded [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rear brake lining manufacturer:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Japan Brake Industries [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rear brake lining code:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] CP26 [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rear brake lining material:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] Semi-metallic [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rear brake lining size primary:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 4.25" x 1.38" x 0.34" [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rear brake lining size secondary:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 3.62" x 1.42" x 0.34" [/font]
[font=Arial, Helvetica, adobe-helvetica, Arial Narrow]Rear brake shoe thickness:[/font][font=Arial, Helvetica, adobe-helvetica, Arial Narrow] 0.2" backing plate[/font]

I don't know if the '88 is much different, but there was no specific "heavy duty" brake package - they were already a pretty heavy duty item as it was. All C4s had exceptional braking over their predecessors.

 

[Vettefan87]

I think I remember hearing that around 88 or 89, they did get bigger rotors and I think a little bit bigger calipers, but I am not sure what year. I remember reading that with the 86-87 rims you can upgrade to the bigger size rotors. I will have to do some checking...

Okay, from what I found the 88's use a two piston 13 inch rotor, which is the front, I am sure the rears are smaller but haven't found the size yet. I am pretty sure that mine on my vette are just one piston calipers, and I do not think my rotors are that big either. Hope that helps any.

 

[jpastaman9]

from what i have seen- the C4's come with a standard or a heavy duty brake set- i just haven't been able to find out how the cars are marked- we tried identifying the brake sets via the VIN#'s but to no avail. Someone suggested that it was marked either in the area of the spare or the glove box(which doesn't exist)-

maybe tomorrow i will read through the manual.

 

[jpastaman9]

http://www.rjsmith.com/rpo_88.html

check this out- cool page- so now that i know there are two brake packages, short of measuring, can you really tell which is which??

 

[Ken]

I learn something new every day - 1988 provided an option code: J55. Thanks.

 

[jpastaman9]

i went ahead and measured the rotors front and back are the same size- 11.9 so it looks like its a standard brake set-
i also noticed that my front and rear tires are the same 255/50/16zr- as i am thinking of changing out rims and tires- will i be able to mount 17's on the front and 18's on the rear(knowing i will have to buy tires and wheels)??

 

[Edmond]

I know the 17's won't be a problem but I don't know about the 18's.

 

[jpastaman9]

seems like most of the wheel sets that i am looking for for the vette's com in standard- 17's in the front 18's in the back

check out frs:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7963917464&category=66484

 

[c4cruiser]

If your 88 is a coupe and it had the Z51 suspension package, it would have had 17x 9.5" wheels and 275/40-ZR17 tires. If the rjsmith page is correct regarding J55 brakes as being part of RPO Z51 then the front brakes would be 13" diameter rotors. The fact that your car has 255/50-16 tires means that it did not have Z51 and therefore no J55 brakes.

The good news is that you can upgrade to 13" brakes by installing the mounting brackets from a donor car that had the J55 package and getting 13" rotors.

The Z06-style wheels you are looking at on eBay is from AFS Wheels and they sell a set of 4 Z06 wheels in 17x9.5 so you can use a 275/40 tire and have the ability to rotate your tires for better tire wear. All 88-96 cars used a 56mm wheel offset and the AFS wheels will work fine. Check out their website at www.afswheels.com They will sometimes sell the Z06 wheel combo in one size on eBay so you may have to keep looking for them.

They also have "blemished" wheel sets available at much lower prices and they warranty them the same as the new wheels and will ship them for free. It might be worth a phone call to them to see what they have in stock.

 

[jpastaman9]

The good news is that you can upgrade to 13" brakes by installing the mounting brackets from a donor car that had the J55 package and getting 13" rotors

do you have a suggestion on where i might find the mounting brackets- and will that make a difference with respect to the calipers and the rest of the braking system-

thanks for the info!!

 

[IH2LOSE]

Hello to all, I normally spend my time in the C1/C2 section .


Any and all parts you may need for a C4 suspention call on Pat Ikerd http://www.ikerds.com/ I am building a 1962 vette using a C4s suspention I purchased from Pat. He can sell you the parts to convert to 13" rotor.

Baer also has a package with new rotor and over sized calipers

Good Luck

 

[Vettefan87]

Hello to all, I normally spend my time in the C1/C2 section .


Any and all parts you may need for a C4 suspention call on Pat Ikerd http://www.ikerds.com/ I am building a 1962 vette using a C4s suspention I purchased from Pat. He can sell you the parts to convert to 13" rotor.

Baer also has a package with new rotor and over sized calipers

Good Luck

I seen your post about that guy wanting to buy your 66. I guess you didn't huh? Did you end up buying one of the five cars he wanted to sell?? Sorry to hijack the thread...

 

[IH2LOSE]

I seen your post about that guy wanting to buy your 66. I guess you didn't huh? Did you end up buying one of the five cars he wanted to sell?? Sorry to hijack the thread...

I am visiting him earley sunday morning,No plans on selling my car But I am going to visit some of there cars