front disc brake upgrade

Hi all,
It's been awhile since I have posted anything. Just read alot but I have a question I need help with...
Does anyone know if the front rotors from a 91 up Caprice can be used on a 1980-90 model? I want to go with larger rotors. I have 11" now and want to go with 12". Also if anyone know could I just use the rotors off a 80-90 wagon and do I also need the spindles?
Any help would be appreciated.

I haven't done the upgrade to the 12's myself yet. From what I understand that you need the different spindles to allow for the caliper to mount properly.

Edit: About the rotors I don't know. This is for a wagon up till about 91: Front ; w/ 11 Rear Drum ; Overall Dia.: 301.5 ; Min Thick: 24.5 ; Height: 77.3. This is a newer caprice: Front ; w/ 4 Wheel Disc ; OE w/ Alloy Wheels ; Overall Dia.: 301.5 Min Thick: 24.5 ; Height: 118.1 *taken from carparts.com*

Now what I don't understand is the Height differences. They both have the same overall diameter but a different height? This was the same information I got at my local parts store. If anyone knows what is meant by "height" please let us know.

Jason

You will need to do a spindle swap to be able to use the larger rotors, just as Blazin_Jason correctly stated. That's not all, either. The larger rotors will require different wheels as well - the smaller ones have a 5x4.75" bolt pattern with 7/16" studs, while the larger rotors have a 5x5" pattern with 1/2" studs.

1977-1990 B-body 9C1(generally) and wagon, as well as 1991-1996 All Models have the larger, 12" rotors with the 5x5" bolt pattern. 1977-1990 non-9C1(generally) sedans have the 5x4.75" pattern, however some 9C1s from this era may also be found with the 5x4.75" pattern (262 or 305 engines only).

The parts (spindles, springs, rotors, calipers etc) will interchange between 1977 and 1996.

"Height" is taken from the back of the rotor to the center of the hub on the front.

im pretty sure you need the spindles to to mount the calipers

"Height" is taken from the back of the rotor to the center of the hub on the front.

http://www.globalwest.net/1964-72%20disc_brake_conversion_informatio.htm

Use 12-inch rotors off a 1988-1992 1LE Camaro/Firebird GM part # GM 18016035. This is all you will need off the 88-92 Camaro/Firebird. If you want to keep the same 5 on 4.75 bolt pattern.

Silicon - Do you think that the 4cm difference between the 2 rotors would be a problem? Like if I used a pre 91 wagon spindle and these http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=8043211414&sspagename=STRK%3AMEWA%3AIT rotors?

Hey thanks for the advice guys. I knew I could count on you. Asuming I go with the 12" rotor w/ 5 on 5 bolt pattern. Could I just get some rear axles from a 1991-96 Caprice/Impala and use those to keep 5on5 all around? Are the splines the same? Sounds like it would be best to get the 5 by 5 with the 1/2" studs considering this car is getting a stroker this year with a turbo 400.

Spline count is different. It changed in 88 or 89.

You might be better served to get the whole 89+ rearend....